AeroElectric-Archive.digest.vol-dh
June 18, 2004 - July 01, 2004
>
> I guess you have never started a fuel-injected engine. I know my fuel
injected engines like the back of my hand but sometimes it takes even me
more than a few blades to get them to start when they are hot.
I have lots of time in injected aircraft including a couple of Beech 35's
(that I have owned) and its rare that hot starts need more then 5 seconds
using the proper hot starting procedure. However that was a cont and many
lycs have a different fuel system and can be a little harder to start but
that's a design shortcoming on the Lyc.
Even there 10 seconds is longer than needed.
> > Thus depth of discharge cycles is a non issue.
>
> For the most part, yes. But understanding the characteristics of the
different batteries is still a good thing, don't you think?
Yes; but that is taken care of by a simple link note pages of replication on
this list. If I am given a link and I am interested then that is enough. for
me.
> Why are you spending all this time to run down my posting? Did I lie or
something? Gee whiz, I was just trying to make some information available
that has turned out to be very useful to me and it seems like I have stepped
on your toes.
I am sorry you do not desire to accept or listen to another point of Vu but
that is your choice.
Perhaps I missed the you post or missed reading something but I do not
recall any specific info on exactly what you are suggesting.
One needs to get specific on exactly the parts recommended (including
technical data links etc) and how they are wired
And all the while this 3 stage charge is going on the acft bus needs to be
above around 13.5 and below around 14.5 or either the lo or hi voltage
alarms are likely to go off if these are exceeded. Not to mention that the
equipment performs best around 13.8v Not my numbers but generally accepted
I do not claim to be an expert but do challenge what seems to be unrelated
info or incomplete. I am willing to learn but I and I assume others would
like you to get very specific with exactly what you propose including all
the parts (from alternators to the battery and all the sensors and how they
are connected and links so we can look at the technical info ourselves.
Better is not needed as Bob has often suggested to go with the Panasonic
type battery and just replace it every year.
Paul
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: Battery types (Was: 2 batteries, 1 alternator) |
BTW
The Panasonic battery (highly recommended by Bob) is an AGM type battery as
is the Odyssey I have suggested. Most batteries of similar case and ratings
are AGM as Bob has often stated, not gell, as the retail stores often say.
These Panasonic Type batterys are in widespread use and seem to rarely fail
even after years of service. The Optoma is widely being used also.
I have both types here and there is a great difference in long term
performance but the Panasonic still has a lot more cranking amps than needed
as it will start my big V8 in my truck.
Paul
________________________________________________________________________________
| Subject: | Torx Drive Screws |
Actually, Aircraft Spruce has the 82 deg Tinnerman washers. I just bought
some 100 deg ones and was surprised to see the 82 deg listed. Someone must
want them.
Greg Young
>
> PS: It would be possible / permissible to build an amateur
> built experimental aircraft using flat head, 82 degree
> hardware store countersunk screw and matching 82 degree
> countersunk holes throughout, but some DAR or FAA inspector
> may take exception to that practice and I dont know of any
> source for 82 degree Tinnerman type washers. I would not
> recommend going that route.
>
________________________________________________________________________________
| From: | "Rex & Jan Shaw" <rexjan(at)bigpond.com> |
| Subject: | Re Odyssey Batteries |
Well there certainly is a lot being said on list re Odyssey batteries and
the like. Lots of great information on list and from following links. I
think we are all learning a lot here. However believe it or not I am seeking
more info that I can't find and hope someone can help please. I am convinced
that replacing my flooded wet cell with an Odyssey is the way to go and have
one on order. However it's more expensive so I don't want to wreck it. I see
a lot of info on charging that can be followed OK but I am left wondering as
to the suitability of the charging system in my plane. It is a Kitfox with a
Rotax 582. This has the better 264-870 regulator. Is this suitable for the
Odyssey or should I be looking to change it ?
My rotax manual says this regulator puts out 13.5 to 14.5 volts but does
not elaborate further. I am wondering if that means once there is enough
revs to charge that it puts out 14.5 volts until the battery is fairly well
charged then it drops back to 13.5 volts. Does any one know please ?
I have studied all these discharge rates for Odyssey batteries but am left
wondering just what amps my starter draws. Would anyone have an idea please
?
Thanks Rex.
rexjan(at)bigpond.com
________________________________________________________________________________
| From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
| Subject: | Ringing out wires |
Old Bob,
"It is my understanding that early electricians would run a batch of wires
through a home or other structure. In order to determine the continuity,
they
would hook up a battery powered door bell between the wire and ground, then
check the far ends to ground. When they found the correct wire, the door
bell
would ring. Thus the term, "ring out the wire." "
Hi, Bob, I learn something here every day! I had no idea I was ringing!
Ferg
________________________________________________________________________________
| From: | "Chiocchio, Stanley" <schiocchio(at)olhcc.edu> |
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________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Wire Marking |
In a message dated 6/19/04 9:20:07 AM Central Daylight Time,
schiocchio(at)olhcc.edu writes:
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Good Morning Stanley,
The message above came through as unintelligible code. Any possibility you
could resend it in a mode that we computer illiterates could read?
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Airpark LL22
Downers Grove, IL 60516
630 985-8502
________________________________________________________________________________
| From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
| Subject: | Brian and batteries |
Brian,
Allow me to second the remarks of Schroeder in supporting your
careful, long and comprehensive article. I also copied some of the remarks
and rebuttals for clarification.
I appreciate your taking the trouble to describe some of the
battery actions I had failed to comprehend - and perhaps last but not least,
doing so without some of the spelling and grammatical errors obvious in
others'!
Cheers and Happy Landings......
Ferg
Europa A064
________________________________________________________________________________
| From: | "Chiocchio, Stanley" <schiocchio(at)olhcc.edu> |
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________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Battery types (Was: 2 batteries, 1 alternator) |
Ken wrote:
> I'm also paying attention to your posts as I have chosen small Dekka
> ETX9 batteries and it seems clear that small AGM batteries will not
> tolerate as much overcharging abuse as large flooded batteries.
No, they won't. They will die an early death.
> I didn't
> know that 3 state VR's existed before your post although I did know that
> was the preferred charging method. Unfortunately it seems they are more
> expensive than my alternators and batteries combined so I will monitor
> my batteries carefully and perhaps try a few simple things once I get
> flying.
That is true and it may be cheaper to just keep replacing batteries. OTOH, spending
a couple hundred bucks on a proper charge controller will help your batteries
last for many years thus eliminating the need to buy new batteries every
year.
As for expense, there are many options. I happen to like Ample Power but they
are the Rolls Royce of alternator charge controllers and cost as such. The SAR3
I chose for my boat and will probably use in my airplane lists for $449. But
even there you can get better deals if you shop around. Ample Power also makes
their analog regulator, the NextStep, which has a list price of $349. This
is also a very good regulator.
Xantrex and Balmar make alternator controllers with current limiting and three-stage
battery charging. Since they are less specialized and serve a larger market,
their prices are lower. A really quick check found the Xantrex XAR alternator
regulator for $220 and I know the site is not a discount site. I am sure
you can find it cheaper elsewhere. I suspect that getting something under
$200 makes it a lot more palatable to many people building airplanes on a budget.
BTW, most internally regulated automotive alternators can be modified for external
regulation. That may be something to consider if you want to save some money.
> I suspect that proper care and feeding of these critters will
> become a bigger concern as they become more common and we start taking
> advantage of smaller lighter batteries.
I agree.
> I was aware of the Dekka white
> paper but your reports of battery failures are more telling in terms of
> real world results. Perhaps you'd care to elaborate on the failures such
> as time to failure and average trip times during service...
I was using Concorde AGMs in my Comanche. I went through three batteries in about
four years with the battery failing to the point where it would not reliably
crank the engine when hot. Switching back to flooded-cell batteries solved
the problem and the Comanche now gets about 3-4 years from a battery. When your
battery can't crank your engine you know it is really far gone and should
have been replaced long ago. One needs to do capacity testing of the battery
every 6 months or a year. The FAA is now requiring that at annual for certified
aircraft.
One of the issues is that I typically fly the Comanche on long cross countries.
The battery has a chance to charge and then overcharge. When I fly three 3-hour
legs in a day (not uncommon for me to do several times per year) the battery
is going to overcharge.
BTW, the time the AGM lasted longest was when I was commuting daily to work, two
45-minute flights per day and the airplane sitting for protracted periods of
time otherwise. In that case the battery didn't really have time to overcharge
much and then had a rest where the gasses could recombine. Still, the battery
only lasted two years in that service.
> This thread
> reminds me of the car that we put a dashboard knob on to adjust the
> voltage and stop the rapid electrolyte loss on long summer trips. That
> was with a mechanical regulator with no temperature compensation at all.
Well, you were part of the feedback loop and dropped the voltage to the proper
float voltage manually. That will work if you are diligent. No reason you can't
do the same thing in your airplane by switching the VR setpoint from charge
to float.
And that is a good empirical way to determine proper float voltage; keep turning
down the voltage and check water loss until you get to the voltage where the
battery stops using water. I did that with the first UPS I built for myself
back in the early '80s. But I had the advantage that my battery was always as
the same temperature in my basement. It is a lot tougher to do in an airplane
in flight through varying conditions.
> Modern internal VR's have at least some air temperature compensation and
> I suspect that there is some benefit to mounting the battery on the cool
> side of the firewall so it can tolerate a higher than ideal voltage in
> cruise. Worst case is perhaps an external mechanical VR and the battery
> on the hot side of the firewall.
The temp comp in the alternator is there more to protect the alternator than the
battery. If you turn down the VR setpoint the alternator delivers less power
and runs cooler. It does not even come close to setting the voltage properly
to charge the battery.
Keeping the battery cooler helps. Measuring the temperature of the battery and
setting the voltage properly is always correct.
> I don't have a clue whether the John Deere PM alternator regulator on my
> second battery has any temperature compensation in it yet.
I wouldn't bet on it. Regardless, it is not at the battery so you are not adjusting
the VR setpoint based on battery temperature, which is what counts. If
it doesn't have a specific external device to measure the battery temperature,
it is not temperature compensated to prevent damage to the battery. Period.
> My powerplant is a multi port EFI Subaru. Occasionally I'm
> misinterpreted here as my perspective is not necessarily from a Lycoming
> background.
Electrical systems are not a function of the engine so I wasn't really thinking
about Subaru vs. Lycoming. Heck, I even think about my boat's electrical system
in all of this discussion. The thing is, there are more similarities than
differences in electrical systems. You have a power source; e.g. alternator,
solar PV panel, wind-powered generator, etc.; a storage system, i.e. battery
bank; and a distribution system, i.e. various busses. There really are only four
issues in the system design:
1. steady-state power requirements;
2. peak power requirements (starting);
3. worst-case run time if the power source fails;
4. required system reliability.
So this is all a matter of scaling the components and the system topology remains
relatively constant (as Bob has shown with his prepackaged designs).
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Jim Oke <wjoke(at)shaw.ca> |
| Subject: | Re: Phillips head screws |
Further to the below, Canadian builders (and those close enough to
cross-border shop) should be able to buy #6 x 1/2" galvanized Robertsons
with a #0 head which, when used with a tinnerman, work nicely for RV trim
and non-structural applications. These can be found in the aviation
department of most Canadian Tire stores. (For non-GWN residents, this
reference is to a large chain of stores which sell auto parts, hardware,
sporting goods, and all sorts of stuff, including .... tires.)
Jim Oke
RV-6A, RV-3
Winnipeg, MB
----- Original Message -----
From: "Jim Jewell" <jjewell(at)telus.net>
Subject: Re: AeroElectric-List: Phillips head screws
>
> To add just a bit more info Robertson head screws have a square hole that
is
> progressively tapered toward the bottom of the hole. In Canada they are
> commonly found holding manufactured goods such as washers and driers
> etc.together. They are also extensively used in the building trades.
> In use they are less likely to strip out the head.
> If put on the screw driver to reach into tight quarters they will stay put
> some what better.
> They come in a full range of screw fastener types and sizes including
> drywall wood and machine screw applications.
>
> I can send you a picture as this email is much less than a thousand words.
> {[g-)!
>
> Jim in Kelowna the smoke devils stayed in the wires! Yeah !!
>
>
> ----- Original Message -----
> From: "cgalley" <cgalley(at)qcbc.org>
> To:
> Subject: Re: AeroElectric-List: Phillips head screws
>
>
> >
> > Square drive hole.
> >
> > ----- Original Message -----
> > From: "Jerzy Krasinski" <krasinski(at)provalue.net>
> > To:
> > Subject: Re: AeroElectric-List: Phillips head screws
> >
> >
> >
> > >
> > > What is Robertson head screw? Do you have a picture?
> > >
> > > Jerzy
> > >
> > >
> > > ----- Original Message -----
> > > From: "BTomm" <fvalarm(at)rapidnet.net>
> > > To:
> > > Subject: RE: AeroElectric-List: Phillips head screws
> > >
> > >
> > > >
> > > > Unfortunately, Robertson head screws are one of Canada's best kept
> > > secrets.
> > > >
> > > > Bevan
> > > > RV7A
> > > >
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Battery types (Was: 2 batteries, 1 alternator) |
Paul Messinger wrote:
> Alternator current is not battery current. I agree that battery temp is
> important if you want to avoid overcharging the battery. But how much and
> for how long is the issue I am trying to get to. How does the smart charger
> / regulator know how much current is going where given the assumed design of
> only a load meter and no battery current sensor per Bob's designs of late.
> ...
> I simply do not see how the smart charger/regulator or what ever can tell
> about the battery state of charge without looking at the battery in a stand
> alone mode or at least measuring the input current to the battery. You say
> only the battery temp is needed.
Temp input is needed to set the proper charging voltage.
> Clearly I am missing something as the systems I have looked at that include
> this multi stage charging setup assume the battery is independent and ant
> loads go back thru the charge controller.
The smart charger uses the alternator load only to protect the alternator. One
of the prime failure modes of alternator based charging systems using three-stage
charging regulators was the that alternator was called upon to deliver 100%
output for relatively long periods of time while charging big battery banks
on boats and RVs. The alternators would overheat and fail. This led to the creation
of so-called "high output" alternators that had sufficient cooling and
robustness to operate at 100% load for indefinite periods of time. Having alternator
load sensing is more of an issue when using modified automotive alternators
(and aviation alternators I suspect). The alternator controller can then
operate in constant-current mode thus preventing the alternator from exceeding
its safe ratings. One manufacturer, Balmar I think, uses a temperature sensor
on the alternator so it can tell if the alternator is overheating and then
reduce field excitation to limit alternator output.
> I simply do not see how the smart charger/regulator or what ever can tell
> about the battery state of charge without looking at the battery in a stand
> alone mode or at least measuring the input current to the battery. You say
> only the battery temp is needed.
>
> Clearly I am missing something as the systems I have looked at that include
> this multi stage charging setup assume the battery is independent and ant
> loads go back thru the charge controller.
As for properly judging the appropriate cut-off point where the controller switches
from absorption voltage to float voltage, there are two approaches. One
is to actually monitor the current going into the battery and actively determine
battery charge state. On my boat this is accomplished by the energy monitor
which actively determines battery charge state by tracking energy removed from
the battery (including properly calculating Peukert's formula for battery capacity
vs. discharge rate). It knows how to signal the VR to change its voltage
setpoint at the proper time. This is the expensive way to do things but it
is 100% effective.
The other is rather simplistic but works rather well. It turns out that the absorption
charge time is relatively constant so the VR sets a timer when the battery
reaches the absorption charge point (when the battery voltage rises to the
VR setpoint and the alternator is no longer being called upon to deliver 100%
output) and switches to float after that time expires. It is simple and quite
effective. Usually this time is on the order of 1-2 hours. You can measure
the time it takes for the charging current to drop to 5% and then set that
as the absorption time or you can just guess. :-)
What this means to pilots is that, if your flying is mostly in the pattern for
an hour at a time, three-stage charging is probably a moot point because you will
never get past the absorption charge stage into the float charge stage. OTOH,
if you fly cross-country it becomes very important. I suspect that I am
talking more to the guy building the cross-country IFR machine than the guy building
the day VFR fly-an-hour-for-the-fun-of-it airplane.
>>No, it is not. I have suffered numerous failures of AGM batteries in
>
> standard aircraft. If I had needed to rely on my battery to power my
> avionics under instrument conditions, I would have been screwed. My
> research into the charging of these batteries has led me to understand the
> nature of the failure and how it is caused by currently accepted best
> practices in aircraft electrical system design.
>
> Other than Concord (that I would not near my aircraft) I have not heard of
> significant battery problems.
I am limited as to what I can put into my Comanche by what is approved by the FAA.
The problems I had were with Concord batteries.
Regardless, would those batteries have survived if they were being charged properly?
I suspect they would have given good service in that case. Certainly Concord
flooded-cell batteries have given me good service.
>>>First; If I ever have a significant depth of discharge, its because of a
>>>Failure of the electrical system. I would not fly again until I have
>>>determined the reason for the failure and corrected it including
>
> redesign or
>
>>>use of different parts.
>>
>>Wrong. These problems affect battery life even when you are not
>
> discharging the battery.
>
> Never said they did not Just that the average persons flying time per year
> is far short of what I have seen as damaging. This does assume the Alt reg
> is set to a reasonable voltage, and many are set to high.
The point of my post was education. People are going to have to think about how
they are going to want their electrical system to perform. The cross-country
IFR pilot wants to ensure that the battery will carry the necessary loads long
enough to safely complete the flight under IFR conditions. The day VFR pilot
doesn't have the same requirements. A total electrical failure during day
VFR is a minor annoyance. A total electrical failure during night IFR is life
threatening. One must consider the mission, the threats, and the risks in designing
the proper system. And one needs information in order to determine the
threats and the risks.
>>>This includes the need for prolonged attempts to start the engine. If it
>>>takes more than a very few blades or 10 seconds there is a problem that
>>>needs fixing.
>>
>>I guess you have never started a fuel-injected engine. I know my fuel
>
> injected engines like the back of my hand but sometimes it takes even me
> more than a few blades to get them to start when they are hot.
>
> I have lots of time in injected aircraft including a couple of Beech 35's
> (that I have owned) and its rare that hot starts need more then 5 seconds
> using the proper hot starting procedure. However that was a cont and many
> lycs have a different fuel system and can be a little harder to start but
> that's a design shortcoming on the Lyc.
It doesn't matter whether you think that the Lycoming injection system (actually
Bendix RSA) is better or worse than Continental's (I happen to think it is better
because it is a closed-loop servo system based on mass airflow measurement),
the key point is that the problem I described CAN and DOES happen on a regular
basis.
> Even there 10 seconds is longer than needed.
In a perfect world, maybe. If you feed the engine the proper mixture, it will
fire and run. In a hot start that can be difficult and many OBAM aircraft have
very tight cowls that retain heat on the ground causing the entire fuel system
to become heat-soaked. Ensuring the proper mixture then becomes a crap shoot.
They can be a real bitch to hot-start even if you hold your tongue right
and the airplane gods are on your side.
So perhaps you knew the magic incantation to make your engine start in three blades
at all times but I think that the experience of the run-of-the-mill pilot
will be different. I accept that it is possible that the pilot may have a period
of extended cranking which will heat up and discharge the battery. That
is the safest assumption and I prefer to design for that.
As an aside, I have found that if I catch it just right, I can start my Lyc IO-540s
in about three blades on a hot start. But I can only do that about 30% of
the time. I do know that if I use the flooded-start procedure I can always
start the engine but I will need to crank it for about 15 seconds. Undoubtedly
you are a better pilot than I but somehow I have figured out how to operate
the aircraft reliably and can teach others to do so as well.
>>>Thus depth of discharge cycles is a non issue.
>>
>>For the most part, yes. But understanding the characteristics of the
>
> different batteries is still a good thing, don't you think?
>
> Yes; but that is taken care of by a simple link note pages of replication on
> this list. If I am given a link and I am interested then that is enough. for
> me.
Possibly. OTOH I have found that sometimes I am able to make things clearer for
people than the raw data would. I guess that is just me being arrogant so I
apologize.
>>Why are you spending all this time to run down my posting? Did I lie or
>
> something? Gee whiz, I was just trying to make some information available
> that has turned out to be very useful to me and it seems like I have stepped
> on your toes.
>
> I am sorry you do not desire to accept or listen to another point of Vu but
> that is your choice.
I guess I misunderstood what you were saying then. It seemed to me that you were
saying that I was wrong.
> Perhaps I missed the you post or missed reading something but I do not
> recall any specific info on exactly what you are suggesting.
>
> One needs to get specific on exactly the parts recommended (including
> technical data links etc) and how they are wired
Yes, eventually. It is difficult to understand a particular circuit topology unless
you know the background behind it. All my big post was intended to do was
to point out the characteristics of the various battery types and how they
should be treated to get best life out of them. Heck, as Ken Lehman pointed out,
they solved the problem in their car with a mechanical adjustment of the old
mechanical VR. In that they created a three-stage charge controller where
the human was part of the feedback loop. There are many ways to skin the cat.
One of my favorite quotations came from General George S. Patton and reads: "Never
tell a many how to do a job. Tell him what to do and he will surprise you
with his ingenuity." It seems appropriate here.
> And all the while this 3 stage charge is going on the acft bus needs to be
> above around 13.5 and below around 14.5 or either the lo or hi voltage
> alarms are likely to go off if these are exceeded.
The low voltage alarm needn't be set for anything above 13V. Anything above that
and the alternator is on-line and charging the battery. The high voltage alarm
is set for something like 15V. I don't see the problem.
> Not to mention that the
> equipment performs best around 13.8v Not my numbers but generally accepted
Hmm, I have never seen that 13.8V is a hard-and-fast magic number. I know that
many manufacturers of automotive electronics and avionics use that as a nominal
value for testing but I wasn't aware that was a magic number to which equipment
was explicitly designed. Please provide the pointer to the data. I would
like to read it.
These last two things strike me as arbitrary road blocks to make a point. Neither
seems all that real to me.
> I do not claim to be an expert but do challenge what seems to be unrelated
> info or incomplete. I am willing to learn but I and I assume others would
> like you to get very specific with exactly what you propose including all
> the parts (from alternators to the battery and all the sensors and how they
> are connected and links so we can look at the technical info ourselves.
Well, one has to start somewhere. I chose to start with battery characteristics
as I found over many years that most people, even the "experts", didn't know
squat about batteries. I have collected a lot of information over the years
and it really gelled in my mind (sorry, pun intended) in about the last four years
while working on alternative power (solar/wind) and marine electrical systems.
Since Bob seems to be one of the few people actually trying to bring aircraft
electrical systems into the present, this seemed to be a good place to
talk about it.
But I guess it is really a book and not just one posting. I guess I should just
write the whole book and then present it in its entirety instead of presenting
information piecemeal. Still, several people on the list have written to thank
me for the post so I guess some found it useful.
> Better is not needed as Bob has often suggested to go with the Panasonic
> type battery and just replace it every year.
That is certainly a viable alternative. I would hate to have a critical component,
in this case a battery, fail on me under hard IFR conditions when operating
it within its design operating range would have ensured that it would perform
properly should the need have arisen.
We spend so much time determining that all the other components in the electrical
system are operated well within their ratings for long life but then turn around
and say that it doesn't matter for the most critical component, the battery.
Well, you pays yer money and you takes yer choice.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | "do-not-arch-ive" |
Ron Koyich wrote:
> (Is this non archiving note read by a computer or a person? Is it
> required?)
Matronics mail computer reads every message. When it sees the Do-not-arch*ive
string of letters it does not save the message for people to look at later when
they peruse the archives.
Matt added this feature a couple of years back because disk storage was getting
tight and people knew when they were making off-hand and off-topic posts that
would not be interesting in the long run. Since then disk storage has gotten
really cheap so that the need to save disk space was less important.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Brian and batteries |
Fergus Kyle wrote:
>
> Brian,
> Allow me to second the remarks of Schroeder in supporting your
> careful, long and comprehensive article. I also copied some of the remarks
> and rebuttals for clarification.
Thank you.
> I appreciate your taking the trouble to describe some of the
> battery actions I had failed to comprehend - and perhaps last but not least,
> doing so without some of the spelling and grammatical errors obvious in
> others'!
I consider myself to be a literate man and I take pains to write clearly and grammatically.
Thank you for noticing.
As I tell my children, in this world of electronic communications what you write
may be the only way some people know you so you want to leave people with the
best impression possible. Some of my postings from the early 1980's are still
archived on the net for people to find so I know anything I write may be around
for a long time.
Having had to "eat my words" on more than one occasion makes me want to keep those
words sweet. ;-)
P.S. my ham call is WB6RQN.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Re Odyssey Batteries |
Rex & Jan Shaw wrote:
> I am convinced
> that replacing my flooded wet cell with an Odyssey is the way to go and have
> one on order. However it's more expensive so I don't want to wreck it. I see
> a lot of info on charging that can be followed OK but I am left wondering as
> to the suitability of the charging system in my plane. It is a Kitfox with a
> Rotax 582. This has the better 264-870 regulator. Is this suitable for the
> Odyssey or should I be looking to change it ?
> My rotax manual says this regulator puts out 13.5 to 14.5 volts but does
> not elaborate further. I am wondering if that means once there is enough
> revs to charge that it puts out 14.5 volts until the battery is fairly well
> charged then it drops back to 13.5 volts. Does any one know please ?
I doubt it does the three-stage charge process. I have only seen that in aftermarket
voltage regulators. I supsect that it just means that the output may be
anywhere from 13.5 to 14.5 volts, not exactly what you want for charging your
battery.
OTOH, I can help you find out. Go ahead and install the odyssey battery but also
install a good expanded-scale voltmeter. Bob used to sell a nice voltmeter/loadmeter
combination that is perfect but I haven't been able to find it recently
on his or B&C's web pages. (Could someone help me out with a pointer here?)
You want to go flying and watch the voltage. If it rises above the proper
charging voltage for an AGM battery, your charging system is doing damage to
the battery. It would be nice to be able to turn the voltage down somehow at
that point.
Here is a problem with the Odyssey battery; I can't find charging voltage vs. temperature
graphs or tables for it. All the factory provides is this:
http://www.odysseyfactory.com/odycharg_a.htm
Since we know that all lead-acid batteries have temperature-dependent charge voltages,
we know that there is information missing from the Odyssey data. They
give charge and float voltages but they don't give them relative to temperature.
Perhaps they assume that the battery will be charged at 70F-80F, the temperature
people keep their houses.
And given that they are AGM batteries I am a bit skeptical of the somewhat high
float voltage. Most AGMs and flooded-cell batteries seem to like float voltages
much lower than that.
But the manufacturer is the final say for the proper operation of their battery.
You should always check the manufacturer's recommendations when setting up
a charging system.
> I have studied all these discharge rates for Odyssey batteries but am left
> wondering just what amps my starter draws. Would anyone have an idea please
> ?
Sorry, but I can't help you there.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | battery charging data |
Odyssey: http://www.odysseyfactory.com/odycharg_a.htm
Deka: http://www.eastpenn-deka.com/cgi-bin/pdfregister.pl?filename=0139.pdf
Concorde: http://www.concordebattery.com/products/technical_info/default.htm
(This doesn't have much on charging but it does have many other interesting
bits of information.)
Panasonic: http://www.panasonic.com/industrial/battery/oem/chem/seal/
http://www.panasonic.com/industrial/battery/oem/images/pdf/Panasonic_VRLA_ChargingMethods.pdf
The latter paper is very interesting in that they point out how critical it is
to long-term battery life to maintain the proper voltage-to-temperature values
for long-term charging. Unfortunately the paper was written by engineers for
engineers and they didn't use dime-sized words where they could use dollar-sized
words instead. :-)
Exide: http://www.exide.com
(I couldn't find much here on charging, just tables giving charge times
vs. charge state. Not useful.)
So there is information out there but you have to find it. Not all the battery
manufacturers provide good charging information. Deka and Panasonic seem to
have the best information on charging their batteries properly.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Battery types (Was: 2 batteries, 1 alternator) |
You know what all this is about? I really want Bob to redesign the LR3 to be a
three-stage regulator/charge controller. You gotta keep up with the times you
know.
;-)
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Tinnerman Washers |
<< AeroElectric-List message previously posted by: "Gregory Young" <gyoung@cs-sol.com>
Actually, Aircraft Spruce has the 82 deg Tinnerman washers. I just
bought some 100 deg ones and was surprised to see the 82 deg listed. Someone
must want them. Greg Young>>
6/19/2004
Hello Greg, Thanks for your input. I have reexamined the Aircraft Spruce catalog,
page 94 of the 2003-2004 edition, and some of my reference material very carefully.
Here are the washers in question:
1) An aviation quality, 100 degree dimpled, countersunk, spring steel, cadmium
plated washer made to the NAS1169 Standard. This Standard also provided for an
aluminum, but not stainless steel, version of this washer. This is the only
true aviation quality Tinnerman washer and is where the name came from.
2) A commercial quality imitation of the above washer made of stainless steel.
Commonly called a Tinnerman washer and widely accepted and used where a stainless
steel version of item 1) is desired. May not have the precise shape called
for in the NAS1169 Standard.
3) An aviation quality, 100 degree countersunk, raised (an oxymoron), cup finishing
washer made to either the NAS 391 or the MS27129 Standards in nickel, or
chromium plated brass and stainless steel.
4) An aviation quality, 100 degree countersunk, flush finishing washer made to
the NAS 390 Standard in nickel or chromium plated brass.
5) A commercial quality 82 degree countersunk, raised finishing washer in stainless
steel similar to item 3).
Of the five washers above only 1) and 2) can be used as, and considered to be
Tinnerman washers. The washer in 5) above, while it involves the terms countersunk
and 82 degrees is not a Tinnerman washer in either shape or usage.
I stand by my statement that I know of no 82 degree countersunk Tinnerman washers.
OC
PS: My apologies to the electrical types reading this list and despairing of these
apparent semantic exercises regarding screws. The only excuses that I can
offer are:
A)These screws are pretty important since they keep our airborne vehicles from
falling apart.
B) There seems to be a great deal of sincere interest in this subject among readers
of this list.
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: New FAA requirement???? |
""One needs to do capacity testing of the battery every 6 months or a year.
The FAA is now requiring that at annual for certified aircraft.""
We all need to know about your above comment. I have asked both the local
FBO and a couple of IA's and no one has ever heard of such a requirement
and also say they do not have the equipment to do any capacity testing.
PLEASE provide a FAA link to this new requirement.
Paul
----- Original Message -----
From: "Brian Lloyd" <brianl(at)lloyd.com>
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Battery data and etc |
Brian
It seems that you do not read my comments and or ignore them. You have
personally attacked me in several posts. I finally have gotten tired of
this.
I have never attacked you personally. Disagreeing with a comment is not a
personal attack (its not an attack just a differernt take on the comment not
the commenter), or most do not take it that was as you seem to do.
I have asked repeatedly for specific info and gotten either no response or
ridicule.
(I will repeat some of my questions on a different post)
Here are a few examples.
EXAMPLE#1
"">> I suggest you look at The ODYSSEY battery. Its very different in many
>> respects.
>I have looked at it and, actually, it's not that different. It is an AGM
battery >using the spiral-wound construction technique. This type of
battery was >designed for UPS applications and has very low internal
resistance right down >to final discharge allowing UPS's to use much smaller
and lighter batteries than >they might otherwise need. The UPS designers
don't expect them to get used >much so they accept a design that represents
a high level of abuse to the >battery.""
Well your reply relates to the Optima not the Odyssey (regarding
construction)and further the latter part of your comment is not at all
consistent with what both manufacturers say about their battery. In fact UPS
is not either of the two main points about their design that advertise.
So you never bothered to READ and respond to what said or you would not
have confused the two manufacturers, And your reply indicated you read
neither mfgrs info for where they both say the intended use of the battery
is.
EXAMPLE #2
>> First; If I ever have a significant depth of discharge, its because of a
>> Failure of the electrical system. I would not fly again until I have
>> determined the reason for the failure and corrected it including redesign
or
>> use of different parts.
>Wrong. These problems affect battery life even when you are not
discharging >the battery.
What is WRONG with my statement and what does battery life have to do with
it??
EXAMPLE #3
>> important if you want to avoid overcharging the battery. But how much and
>> for how long is the issue I am trying to get to. How does the smart
charger
>> / regulator know how much current is going where given the assumed design
>>of
>> only a load meter and no battery current sensor per Bob's designs of
late.
> ...
>> I simply do not see how the smart charger/regulator or what ever can tell
>> about the battery state of charge without looking at the battery in a
stand
>> alone mode or at least measuring the input current to the battery. You
say
>> only the battery temp is needed.
>Temp input is needed to set the proper charging voltage.
Well IF you look at most any battery mfgrs data they will tell you the ONLY
way to tell when to finish and go to the "float" mode is when the battery
current reaches a specific current (depending on the battery). Using battery
voltage under charge is at best a guess.
Paul
Perhaps one or more of the following fits :-)
" I suffer fools badly"
"Its hard to have a battle of wits with an unarmed man"
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: New FAA requirement???? |
In a message dated 6/20/04 9:49:44 AM Central Daylight Time,
paulm(at)olypen.com writes:
--> AeroElectric-List message posted by: "Paul Messinger"
""One needs to do capacity testing of the battery every 6 months or a year.
The FAA is now requiring that at annual for certified aircraft.""
We all need to know about your above comment. I have asked both the local
FBO and a couple of IA's and no one has ever heard of such a requirement
and also say they do not have the equipment to do any capacity testing.
PLEASE provide a FAA link to this new requirement.
Paul
Good Morning Paul,
I am afraid that what Brian has said is true.
If t you will read the Instructions for Continued Airworthiness that come
with any new battery, you will find such requirements.
You won't find a chapter and verse in the FARs that say you must capacity
check a battery. What it does say is that maintenance must be done in
accordance with manufacturers directives.
The FAA is now pressuring all manufacturers and all applicants for an STC to
provide information as to the Directions or Instructions for Continued
Airworthiness.
Therefore, any Instructions For Continued Air Worthiness become the law of
the land unless you can prove to the Administrator that you have a "better
way."
I am not at all surprised that your FBO or IA does not have the current
word. Why don't you ask them if they have ever attended one of the FAA's yearly
IA clinics? Most have not. They renew their IAs by submitting an activity
report. If they annual four airplanes per year, they need no formal training
or checking. I certainly am NOT advocating tougher requirements for IA
renewal, but it is a fact that the FAA has very little capability of getting the
"word" out to people in the field. They do send many monthly communiques, but
those who need the information the most rarely read those communiques.
I agree that most shops do not have the equipment and are not complying with
the capacity check requirements.
To my knowledge, no one has yet gotten in trouble for non compliance, but it
is still non compliance if the capacity check is not performed.
Big Brother is out there, but he is very underfunded and does not always
catch all omissions and deviations from the rule. How many FAA inspectors have
looked at your airplane or gone through your paperwork?
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Airpark LL22
Downers Grove, IL 60516
630 985-8502
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
Much has been said about how battery life can be shortened by overcharging.
Agreed; but what is important is how much is it shortened and under what
conditions. So far no specifics have been suggested. Simply saying a
specific battery failed in X months without also specific battery average
temps and very important the charging voltage. Spam cans were designed for
flooded cell batteries and short flights and thus have higher voltages to
recharge the battery faster. The same is true for most automobiles.
Taking a battery and giving it the recommended 3 stage treatment may make it
a 10 year battery but in the real world of the AVERAGE experimental aircraft
and average aircraft usage just what is the time to "Early death".
Much has been said about overcharging after the battery has been fully
charged and how the voltage needs to be reduced. All correct as I can
recall.
However Odyssey states that such over voltage can exist for up to 24 hours
after full charge and then the voltage needs to be reduced. The charge
voltage specified is 14.4 to 14.7 and this is well within the range of the
regulators we use.
So If I fly for 6 hours and then the next day use the battery for starting
its no longer fully charged and in theory I can restart the 24 hour max
limit.
Poor conclusion; I agree but my point is 1-6 hour flights are far less than
the 24 hour max imposed by the mfgr.
Optima has different limits. The voltage limit is higher at 15.0 and the
Time limit is less at 8 hours.
Panasonic says 3 hours after charging current stabilizes, the battery is
fully charged, thus saying that 3 hours at the higher voltage is OK. The
charging voltage upper limit is 14.9.
So we have upper limits of 14.7, 14.9 15.0 and time limits of 3, 8, and 24
hours.
(This is for ABM type batteries but clearly they are different. So lets not
paint with a broad brush and group batteries as AGP, vs Gell vs etc etc.)
Thus its reasonable to conclude if your flights are 3 hours or less and your
regulated alternator voltage is 14.4-14.7 you meet the requirements of the
manufacturers of these three batteries for normal life times.
No where can I find any data on specific shortening of life (times and
conditions) other than the above
Panasonic also discusses temperature compensation of charging vs battery
life.
30 deg C compensation prolongs life by 5%,, 35C..10% and 40C..15%.
Not much gained or lost and not worth the bother in most cases.
Automotive external voltage regulators have built-in temperature
compensation and if you install the regulator in the same area as the
battery you get automatic compensation for free and no external temp monitor
needed. (I would guess the B&C regulators require the temp sensor to
compensate as that is an option)
Paul
________________________________________________________________________________
| From: | <bakerocb(at)cox.net> |
| Subject: | Phillips Head Screws |
<
Further to the below, Canadian builders (and those close enough to
cross-border shop) should be able to buy #6 x 1/2" galvanized Robertsons
with a #0 head which, when used with a tinnerman, work nicely for RV
trim and non-structural applications. These can be found in the aviation
department of most Canadian Tire stores. (For non-GWN residents, this
reference is to a large chain of stores which sell auto parts, hardware,
sporting goods, and all sorts of stuff, including .... tires.)Jim Oke RV-6A, RV-3
Winnipeg, MB>>
6/20/2004
Hello Jim, Undoubtedly those Robertson screws with countersunk heads are with an
82 degree countersink angle -- -- the standard angle for common hardware store
flat head screws. The standard aviation Tinnerman washer will have a 100 degree
countersink dimple.
There is no law prohibiting the mixing of hardware using the two different countersink
angles, but the builder should be aware of the mismatch and the attendant
loss of screw head to base material or washer contact that results.
This mismatch can result in weakened fastener joints and open spaces that allow
debris, moisture, and the resulting corrosion to exist.
OC
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | engine hot starting |
Another lack of reading and understanding
>>>This includes the need for prolonged attempts to start the engine. If it
>>>takes more than a very few blades or 10 seconds there is a problem that
>>>needs fixing.
>>
>>I guess you have never started a fuel-injected engine. I know my fuel
>> injected engines like the back of my hand but sometimes it takes even me
>> more than a few blades to get them to start when they are hot.
I never JUST said a few blades, read it again I included 10 seconds to cover
hot starts. I resent you comment about my knowledge of injected engines.
I do know 99% of owners have a heck of a time with hot starts and most say
they are using the acft manual procedure. Well I had problems with my Beech
hot starting until I forgot the manual and was told how to start just about
any brand or injected engine works every time and seldom more than a few
seconds.
> I have lots of time in injected aircraft including a couple of Beech 35's
> (that I have owned) and its rare that hot starts need more then 5 seconds
> using the proper hot starting procedure. However that was a cont and many
> lycs have a different fuel system and can be a little harder to start but
> that's a design shortcoming on the Lyc.
It doesn't matter whether you think that the Lycoming injection system
(actually Bendix RSA) is better or worse than Continental's (I happen to
think it is better because it is a closed-loop servo system based on mass
airflow measurement), the key point is that the problem I described CAN and
DOES happen on a regular basis.
I agree it happens on a regular basis but I disagree it needs to happen
nearly as often. I have yet to see the fool proof hot start procedure in any
manual.
The best system in my opinion is the one on the S35 and its so unique its
got a special section in the A&P manual. One simple dual spool rotary valve
and easy to use and dirt simple. Works all the time!
The Cont systems I have personal experience have a fuel pump return line
back to the tank and the Lyc's have no return line. Thus not only is the
fuel in the low pressure injecton lines boiled off but the engine driven
pump heats its fuel and in the LYC case you cannot flush the hot fuel out so
those designs are designed to be harder to start.
> Even there 10 seconds is longer than needed.
In a perfect world, maybe. If you feed the engine the proper mixture, it
will fire and run. In a hot start that can be difficult and many OBAM
aircraft have very tight cowls that retain heat on the ground causing the
entire fuel system to become heat-soaked. Ensuring the proper mixture then
becomes a crap shoot. They can be a real bitch to hot-start even if you
hold your tongue right and the airplane gods are on your side.
See above My experience appears to differ
So perhaps you knew the magic incantation to make your engine start in three
blades at all times but I think that the experience of the run-of-the-mill
pilot will be different. I accept that it is possible that the pilot may
have a period of extended cranking which will heat up and discharge the
battery. That is the safest assumption and I prefer to design for that.
So what and what is your point as the number of deep cycles in the battery
is small compared to the battery design if you choose the proper battery.
Paul
________________________________________________________________________________
| From: | "Dan Morrow" <DanFM01(at)butter.toast.net> |
| Subject: | Re: New FAA requirement???? |
The December 2003 and January 2004 issues of "The Aviation Consumer"
contain interesting articles on batteries. They quote FAR 43.16 and 91.203
as recently amended to require the manufacturer's ICA's (Instructions for
Continued Airworthiness) to be followed. Several of the battery
manufacturers are now shipping new batteries with ICA's.
Dan Morrow
RV8A Building Empennage slowly
----- Original Message -----
From: "Paul Messinger" <paulm(at)olypen.com>
Subject: Re: AeroElectric-List: New FAA requirement????
>
> ""One needs to do capacity testing of the battery every 6 months or a
year.
> The FAA is now requiring that at annual for certified aircraft.""
>
> We all need to know about your above comment. I have asked both the local
> FBO and a couple of IA's and no one has ever heard of such a requirement
> and also say they do not have the equipment to do any capacity testing.
>
> PLEASE provide a FAA link to this new requirement.
>
> Paul
>
> ----- Original Message -----
> From: "Brian Lloyd" <brianl(at)lloyd.com>
> To:
>
>
---
________________________________________________________________________________
| Subject: | New FAA requirement???? |
| From: | "George Braly" <gwbraly(at)gami.com> |
>>The FAA is now pressuring all manufacturers and all applicants for an
STC to provide information as to the Directions or Instructions for
Continued Airworthiness.<<
Bob, It is not just "pressuring" - - the FAA absolutely requires that
there be instructions for continuing airworthiness on all new STCs - -
and they do actively review the proposed instructions before the issue
the STC.
It is probably a good rule - - if properly executed - - and a bad rule,
otherwise.
Regards, George
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: New FAA requirement???? |
Thanks for the heads up.
FAA is trying to keep up with NASA with the requirement for paperwork.
IE It must exceed the height and weight of the craft before flight.
I just read the Concord battery version of the ICA. Makes annuals at least 2
days just to test the battery and most of the time around here the battery
must be physically removed to a heated room storage for 24 hours before the
test.
Paul
>
> Good Morning Paul,
>
> I am afraid that what Brian has said is true.
>
> If you will read the Instructions for Continued Airworthiness that come
> with any new battery, you will find such requirements.
>
> You won't find a chapter and verse in the FARs that say you must capacity
> check a battery. What it does say is that maintenance must be done in
> accordance with manufacturers directives.
>
> The FAA is now pressuring all manufacturers and all applicants for an STC
to
> provide information as to the Directions or Instructions for Continued
> Airworthiness.
>
> Therefore, any Instructions For Continued Air Worthiness become the law of
> the land unless you can prove to the Administrator that you have a "better
> way."
>
________________________________________________________________________________
| From: | "Dan Morrow" <DanFM01(at)butter.toast.net> |
| Subject: | Re: New FAA requirement???? |
Sorry, that should have been FAR 91.403 not 91.203.
Dan Morrow
RV8A Building Empennage slowly
----- Original Message -----
From: "Dan Morrow" <DanFM01(at)butter.toast.net>
Subject: Re: AeroElectric-List: New FAA requirement????
>
> The December 2003 and January 2004 issues of "The Aviation Consumer"
> contain interesting articles on batteries. They quote FAR 43.16 and
91.203
> as recently amended to require the manufacturer's ICA's (Instructions for
> Continued Airworthiness) to be followed. Several of the battery
> manufacturers are now shipping new batteries with ICA's.
>
> Dan Morrow
> RV8A Building Empennage slowly
> ----- Original Message -----
> From: "Paul Messinger" <paulm(at)olypen.com>
> To:
> Subject: Re: AeroElectric-List: New FAA requirement????
>
>
>
> >
> > ""One needs to do capacity testing of the battery every 6 months or a
> year.
> > The FAA is now requiring that at annual for certified aircraft.""
> >
> > We all need to know about your above comment. I have asked both the
local
> > FBO and a couple of IA's and no one has ever heard of such a
requirement
> > and also say they do not have the equipment to do any capacity testing.
> >
> > PLEASE provide a FAA link to this new requirement.
> >
> > Paul
> >
> > ----- Original Message -----
> > From: "Brian Lloyd" <brianl(at)lloyd.com>
> > To:
> >
> >
>
>
> ---
>
>
---
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: New FAA requirement???? |
In a message dated 6/20/04 11:04:42 AM Central Daylight Time,
gwbraly(at)gami.com writes:
Bob, It is not just "pressuring" - - the FAA absolutely requires that
there be instructions for continuing airworthiness on all new STCs - -
and they do actively review the proposed instructions before the issue
the STC.
Good Morning George,
You are, as usual, completely correct. My thoughts were more toward the
idea that the FAA is pressuring folks who hold older STCs to come up with an ICA
for the older equipment.
Do you have any idea what is the status of that effort?
It is my understanding that the ICA rules have been on the books since about
1992, but have not been enforced until recently.
Could open up a major can of worms!
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Airpark LL22
Downers Grove, IL 60516
630 985-8502
________________________________________________________________________________
| Subject: | Characterization of Westach 720-4a sensor |
| From: | irampil(at)notes.cc.sunysb.edu |
06/20/2004 02:29:16 PM,
Serialize complete at 06/20/2004 02:29:16 PM
Greetings,
Has anyone seen or developed a characterization of this tach sensor?
It is a combined magnet/coil combo used to generate a pulse when a
bit of iron speeds past(Ampere's law). In my case, I have 6 steel AN5
bolt
heads/revolution roughly 3/32" from the sensor head at roughly 1000
inches/sec max.
I'd like to know the expected output voltage and impedance so I can
compute the
input resistor for a 4n25. I need to divide the output pulse rate by 4
with a little TTL to
get it into the frequency range for my tachometer system.
Any advice?
Ira N224XS flying, but due for a little panel rework
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Battery data and etc |
Paul Messinger wrote:
> [stuff deleted]
>>I have looked at it and, actually, it's not that different. It is an AGM
>> battery using the spiral-wound construction technique. This type of
>> battery was designed for UPS applications and has very low internal
>> resistance right down to final discharge allowing UPS's to use much smaller
>> and lighter batteries than they might otherwise need. The UPS designers
>> don't expect them to get used much so they accept a design that represents
>> a high level of abuse to the battery.""
>
> Well your reply relates to the Optima not the Odyssey (regarding
> construction)and further the latter part of your comment is not at all
> consistent with what both manufacturers say about their battery. In fact UPS
> is not either of the two main points about their design that advertise.
>
> So you never bothered to READ and respond to what said or you would not
> have confused the two manufacturers, And your reply indicated you read
> neither mfgrs info for where they both say the intended use of the battery
> is.
No it isn't what the manufacturers currently advertise their batteries for but
I am going back to the technology driving the design of small, high power density,
AGM batteries.
One of the problems with lead-acid batteries is a relatively high internal resistance.
This means that the voltage sags when you pull current out of it and
sags even more as the battery discharges. The traditional solution was to make
the battery really big and heavy to increase the current delivery capability.
Some people went in the direction of using NiCd batteries for their high power
density (starting turbine engines comes to mind here) but they are very expensive
and more difficult to charge safely.
Then someone realized that if they could make the plate area of a lead-acid battery
really big and reduce the plate spacing, they could pack a lot more capacity
into a smaller package AND lower internal resistance. Voila! The spiral-wound
AGM was born. The glass mat provides 100% effective insulation and plate
spacing as well as holding the electrolyte. The plates are lead foil wrapped
in a spiral which makes for very large surface area in a relatively small volume.
As I recall, Gates was the first maker of these small, high power-density
cells.
The big market for these batteries was and is the small UPS market. The batteries
are cheap to make but can deliver huge current for a short period of time.
It is no small wonder that someone figured out that they are ideal for starting
engines. You only need power for a few seconds at a time.
So I stand by my early comments about UPS technology even if the manufacturer does
not mention it in their literature. That is what drove the development of
these compact AGMs. And even if Odyssey is not using spiral winding, the basic
premise of using foil plates with a thin glass mat is still applicable. I
would bet that Odyssey is not using spiral winding because of patent issues and
had to come up with a way to do the same thing without having to pay royalties
for the spiral winding technique.
But I admit to a fair bit of speculation here.
> EXAMPLE #2
>> Wrong. These problems affect battery life even when you are not
>> discharging >the battery.
>
> What is WRONG with my statement and what does battery life have to do with
> it??
Even if you do not significantly discharge the battery, the way you recharge it
has a significant effect on battery life. When you crank an engine for 10 seconds
drawing 200A, you are using only 0.55AH of the battery's capacity. (I will
not get into Peukert's formula here as it will just bog the discussion down
in a bunch of nitty-gritty detail that won't really help others understand.
Regardless, I do understand Peukert's formula and how battery capacity varies
with the rate of discharge.) That means that you have used only a few percent
of the battery's charge. It is still almost fully charged. Now you throw it
on a full charge regimen and you are guaranteed to overcharge the battery. You
want to drop back to a float charge very early on if possible.
So even if we are not going to deep-cycle the battery, we are in need of setting
the charge and float voltages appropriate to the temperature of the battery
for long battery life.
This of course would lead into a discussion of it being better if the charge controller
would monitor both battery voltage and charge current to determine that
the battery is done charging. I think you mentioned that before and I agree
with you that is the best way to do things.
> EXAMPLE #3
>>Temp input is needed to set the proper charging voltage.
>
>
> Well IF you look at most any battery mfgrs data they will tell you the ONLY
> way to tell when to finish and go to the "float" mode is when the battery
> current reaches a specific current (depending on the battery). Using battery
> voltage under charge is at best a guess.
In a constant-voltage charge, i.e. the voltage is held at the proper voltage for
the absorption portion of the charge cycle, voltage tells you nothing so therefore,
you are correct. You need to know either the prior state of the battery
and can monitor the number of coulombs replaced (LA batteries are amazingly
consistent in their coulombic efficiency), you need to monitor the end-of-charge
charging current, or you need to monitor the time that the battery stays at
the absorption charge voltage before switching to float voltage. The latter
is a hack but it is surprisingly effective and many modern three-stage battery
chargers use the technique.
It turns out that the time differs a little from battery to battery but is is surprisingly
consistent for a particular battery. The trick is to watch the battery
recharge and monitor the time from when the battery reaches constant voltage
until the charging current trails off to 5% of the 20-hour AH rating, e.g.
1A for a 20AH battery. Once you know that you can set the absorption time and
pretty much forget it after that.
But all of that aside, the proper absorption and float voltages are still dependent
on temperature so you still need a temperature-sensing charge controller
(voltage regulator).
(BTW, the term "hack" is from the computer geek world and refers to a quick-and-dirty
program that turns out to be surprisingly effective and useful in the long
run.)
> Paul
> Perhaps one or more of the following fits :-)
>
> " I suffer fools badly"
That is too bad. I have learned to suffer them well because today's fool MAY become
a learned man through intelligent and reasoned discourse.
> "Its hard to have a battle of wits with an unarmed man"
Most assuredly you are a wit. Unfortunately I fear I have a tendency to be only
half-right.
Now that we have traded ideas and insults, may I buy you a beer at OSH so we can
discuss battery and charging technology at greater length?
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: New FAA requirement???? |
Paul Messinger wrote:
>
> ""One needs to do capacity testing of the battery every 6 months or a year.
> The FAA is now requiring that at annual for certified aircraft.""
>
> We all need to know about your above comment. I have asked both the local
> FBO and a couple of IA's and no one has ever heard of such a requirement
> and also say they do not have the equipment to do any capacity testing.
>
> PLEASE provide a FAA link to this new requirement.
Well, I feel a little stupid here. I was given the information by what I consider
to be a reputable source but have now repeated the information without checking
it. I can't find any reference to it on any of the FAA web sites I can
get to but I have found references to capacity testing at the following sites:
http://www.concordebattery.com/products/technical_info/servicealert_RF80-K.htm
http://www.jfmeng.com/serv03.htm
I will continue to try to find the original reference.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: engine hot starting |
Paul Messinger wrote:
> I do know 99% of owners have a heck of a time with hot starts and most say
> they are using the acft manual procedure. Well I had problems with my Beech
> hot starting until I forgot the manual and was told how to start just about
> any brand or injected engine works every time and seldom more than a few
> seconds.
I agree that the hot-start technique usually provided in the pilot's handbook doesn't
work very well. With Lycoming or Continental engines I find that the flooded
start technique works quite well although it does require a bit of cranking.
The technique I use is as follows:
1. Throttle and mixture full forward, i.e. full throttle and rich mixture.
2. Boost pump on until you see a stable fuel-flow indication. This means the
vapor is purged from the system.
3. Mixture to idle-cut-off (ICO) and boost pump off.
4. Crank the engine.
5. When the engine fires, retard the throttle and advance the mixture.
This technique works very reliably as the fuel lines and other components are cooled
with fresh fuel and fuel vapor is purged from the lines. The problem now
is that the engine is just about guaranteed to be flooded. Cranking with the
throttle wide open admits the maximum amount of air and the mixture at ICO precludes
any more fuel being admitted to the engine. As the engine cranks the
mixture, which was initially too rich to fire, becomes progressively leaner until
the engine fires. At that point the throttle is retarded and the mixture
advanced to allow the engine to operate normally.
>> It doesn't matter whether you think that the Lycoming injection system
>> (actually Bendix RSA) is better or worse than Continental's (I happen to
>> think it is better because it is a closed-loop servo system based on mass
>> airflow measurement), the key point is that the problem I described CAN and
>> DOES happen on a regular basis.
>
> I agree it happens on a regular basis but I disagree it needs to happen
> nearly as often. I have yet to see the fool proof hot start procedure in any
> manual.
I agree with both of your statements.
> The best system in my opinion is the one on the S35 and its so unique its
> got a special section in the A&P manual. One simple dual spool rotary valve
> and easy to use and dirt simple. Works all the time!
It does have the advantage of being simpler than the Bendix RSA system but it has
no mechanism to prevent the engine from getting too rich to operate. Leaving
the boost pump in the high position can flood even a running engine.
> The Cont systems I have personal experience have a fuel pump return line
> back to the tank and the Lyc's have no return line. Thus not only is the
> fuel in the low pressure injecton lines boiled off but the engine driven
> pump heats its fuel and in the LYC case you cannot flush the hot fuel out so
> those designs are designed to be harder to start.
The "flooded start" procedure I outlined above works quite well but you may have
to crank for 15 seconds or so depending on how much fuel you had to push through
the injection system to purge the fuel vapor.
I also like the fact that the Bendix fuel servo compensates for changes in fuel
pressure and adjusts the flow accordingly. Also the mass airflow sensing causes
the mixture to be more consistent as the aircraft changes altitude thus reducing
cockpit workload for the pilot during climb and descent.
Both systems work pretty well but they are very different. I do find it interesting
to note that the popular modern aftermarket continuous-flow injection systems
from Airflow Performance are based on the principles in the Bendix RSA system.
The Bendix RSA fuel injection system is pretty old now and could use some
updating but we all know how likely that is given the regulatory nature of
the FAA. Bendix has no motivation to improve their system.
>> In a perfect world, maybe. If you feed the engine the proper mixture, it
>> will fire and run. In a hot start that can be difficult and many OBAM
>> aircraft have very tight cowls that retain heat on the ground causing the
>> entire fuel system to become heat-soaked. Ensuring the proper mixture then
>> becomes a crap shoot. They can be a real bitch to hot-start even if you
>> hold your tongue right and the airplane gods are on your side.
>
> See above My experience appears to differ
Great! I am eager to learn. What is your technique? My technique works but I
would much rather save the wear and tear on the starter and battery if possible.
>> So perhaps you knew the magic incantation to make your engine start in three
>> blades at all times but I think that the experience of the run-of-the-mill
>> pilot will be different. I accept that it is possible that the pilot may
>> have a period of extended cranking which will heat up and discharge the
>> battery. That is the safest assumption and I prefer to design for that.
>
> So what and what is your point as the number of deep cycles in the battery
> is small compared to the battery design if you choose the proper battery.
If you recall, I was pointing out how a thermal runaway event in a battery could
be initiated on a hot day with a prolonged cranking event and how a high initial
charge rate could exacerbate the problem. Temperature sensing on the battery
would reduce the voltage and hence the charge rate thus saving the battery.
I wasn't talking about deep cycles at all.
I think that we got off on the wrong foot when I pointed out that AGMs have shorter
lifetimes in deep cycle service than do gell-cells. I agree that deep cycle
service is unusual in an aircraft except where there is a failure and that
is not normal operation. But I did want to emphasize that there is confusion
in people's minds between gell-cell batteries and AGM batteries and that you
need to adjust the charging system to accommodate the type of battery you have
installed in your aircraft and the temperature at which that battery is operating.
One thing that *is* worth considering is that the difference between charge and
float voltages in gell-cell batteries are much closer together than are the charge
and float voltages for flooded-cell and AGM batteries. If you are going
to have a charging system with only a single set-point, I think you may find
that the gell-cell lives longer than the AGM in that environment.
In my RV-4 I installed an over-sized gell-cell that would power my e-buss for 4
hours, the normal fuel duration of the aircraft. I knew that if I got to the
end of the battery capacity, I probably had other, more pressing problems to
deal with. The point is that the bigger gell-cell was able to crank the O-320
very happily thus validating the "bigger battery means more current" philosophy.
And you may be right that the Odyssey battery is the be-all and end-all of batteries.
It may be so robustly constructed that it takes the abuse without damage
so all this may be a moot point.
But I still believe that one should operate all the devices in an aircraft as conservatively
as possible. It won't hurt your Odyssey battery to perform a proper
three-stage charge cutting off to the proper float voltage, will it?
Pax?
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: New FAA requirement???? |
Dan Morrow wrote:
>
> The December 2003 and January 2004 issues of "The Aviation Consumer"
> contain interesting articles on batteries. They quote FAR 43.16 and 91.203
> as recently amended to require the manufacturer's ICA's (Instructions for
> Continued Airworthiness) to be followed. Several of the battery
> manufacturers are now shipping new batteries with ICA's.
Thank you Dan. That is where I remember seeing the requirement for capacity testing.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Characterization of Westach 720-4a sensor |
irampil(at)notes.cc.sunysb.edu wrote:
> I'd like to know the expected output voltage and impedance so I can
> compute the
> input resistor for a 4n25. I need to divide the output pulse rate by 4
> with a little TTL to
> get it into the frequency range for my tachometer system.
>
> Any advice?
Well, you can look at it with a scope. That takes all the guesswork out of the
problem.
You can amplify the signal with an op-amp and use some small-signal or a pair of
back-to-back zener diodes in the feedback loop to square the peaks. The op-amp
will operate more-or-less open-loop until the diodes or the zeners conduct.
With an appropriate offset you should get a nice pulse that will make TTL or
CMOS happy. A fast-recovery, no-latch-up op-amp running from a single-ended
supply should work just peachy. This is an old technique for applying an analog
pulse to digital circuitry.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| Subject: | engine hot starting |
| From: | "George Braly" <gwbraly(at)gami.com> |
Brian,
Your technique is common for hot starts.
It is not the technique that makes use of knowledge as to what the real
problem is. And it is a technique that can be very dangerous and cause
a fire that can and has consumed an airplane.
Getting fuel flow indications may indicate that "vapor is purged" - -
but is not at all an indication that you are not going to vapor lock
about 3-5 seconds after the engine fires up - - and then promptly stops.
The reasons these engines are hard to start when HOT is very simple.
The fuel pump core is HOT - - so hot that when new fuel hits the core of
the engine driven fuel pump it flashes to vapor and vapor locks the
inlet to the fuel pump.
Until you sufficiently cool off the core of the fuel pump it will ALWAYS
- - ALWAYS vapor lock.
You either have to:
1) cool off the core of the engine driven fuel pump (easy with a TCM
fuel system); or,
2) You have to use the electric boost pump to keep the engine running
until the core of the engine driven pump does cool off enough to quit
flashing the incoming fuel to vapor (typical Lycoming and some twin
Cessna techniques).
After the fuel pump core components are cooled off, the engine will
actually start better than when cold.
Regards, George
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Brian
Lloyd
Subject: Re: AeroElectric-List: engine hot starting
Paul Messinger wrote:
> I do know 99% of owners have a heck of a time with hot starts and most
say
> they are using the acft manual procedure. Well I had problems with my
Beech
> hot starting until I forgot the manual and was told how to start just
about
> any brand or injected engine works every time and seldom more than a
few
> seconds.
I agree that the hot-start technique usually provided in the pilot's
handbook doesn't work very well. With Lycoming or Continental engines I
find that the flooded start technique works quite well although it does
require a bit of cranking. The technique I use is as follows:
1. Throttle and mixture full forward, i.e. full throttle and rich
mixture.
2. Boost pump on until you see a stable fuel-flow indication. This
means the vapor is purged from the system.
3. Mixture to idle-cut-off (ICO) and boost pump off.
4. Crank the engine.
5. When the engine fires, retard the throttle and advance the mixture.
This technique works very reliably as the fuel lines and other
components are cooled with fresh fuel and fuel vapor is purged from the
lines. The problem now is that the engine is just about guaranteed to
be flooded. Cranking with the throttle wide open admits the maximum
amount of air and the mixture at ICO precludes any more fuel being
admitted to the engine. As the engine cranks the mixture, which was
initially too rich to fire, becomes progressively leaner until the
engine fires. At that point the throttle is retarded and the mixture
advanced to allow the engine to operate normally.
>> It doesn't matter whether you think that the Lycoming injection
system
>> (actually Bendix RSA) is better or worse than Continental's (I happen
to
>> think it is better because it is a closed-loop servo system based on
mass
>> airflow measurement), the key point is that the problem I described
CAN and
>> DOES happen on a regular basis.
>
> I agree it happens on a regular basis but I disagree it needs to
happen
> nearly as often. I have yet to see the fool proof hot start procedure
in any
> manual.
I agree with both of your statements.
> The best system in my opinion is the one on the S35 and its so unique
its
> got a special section in the A&P manual. One simple dual spool rotary
valve
> and easy to use and dirt simple. Works all the time!
It does have the advantage of being simpler than the Bendix RSA system
but it has no mechanism to prevent the engine from getting too rich to
operate. Leaving the boost pump in the high position can flood even a
running engine.
> The Cont systems I have personal experience have a fuel pump return
line
> back to the tank and the Lyc's have no return line. Thus not only is
the
> fuel in the low pressure injecton lines boiled off but the engine
driven
> pump heats its fuel and in the LYC case you cannot flush the hot fuel
out so
> those designs are designed to be harder to start.
The "flooded start" procedure I outlined above works quite well but you
may have to crank for 15 seconds or so depending on how much fuel you
had to push through the injection system to purge the fuel vapor.
I also like the fact that the Bendix fuel servo compensates for changes
in fuel pressure and adjusts the flow accordingly. Also the mass
airflow sensing causes the mixture to be more consistent as the aircraft
changes altitude thus reducing cockpit workload for the pilot during
climb and descent.
Both systems work pretty well but they are very different. I do find it
interesting to note that the popular modern aftermarket continuous-flow
injection systems from Airflow Performance are based on the principles
in the Bendix RSA system. The Bendix RSA fuel injection system is
pretty old now and could use some updating but we all know how likely
that is given the regulatory nature of the FAA. Bendix has no
motivation to improve their system.
>> In a perfect world, maybe. If you feed the engine the proper
mixture, it
>> will fire and run. In a hot start that can be difficult and many
OBAM
>> aircraft have very tight cowls that retain heat on the ground causing
the
>> entire fuel system to become heat-soaked. Ensuring the proper
mixture then
>> becomes a crap shoot. They can be a real bitch to hot-start even if
you
>> hold your tongue right and the airplane gods are on your side.
>
> See above My experience appears to differ
Great! I am eager to learn. What is your technique? My technique
works but I would much rather save the wear and tear on the starter and
battery if possible.
>> So perhaps you knew the magic incantation to make your engine start
in three
>> blades at all times but I think that the experience of the
run-of-the-mill
>> pilot will be different. I accept that it is possible that the pilot
may
>> have a period of extended cranking which will heat up and discharge
the
>> battery. That is the safest assumption and I prefer to design for
that.
>
> So what and what is your point as the number of deep cycles in the
battery
> is small compared to the battery design if you choose the proper
battery.
If you recall, I was pointing out how a thermal runaway event in a
battery could be initiated on a hot day with a prolonged cranking event
and how a high initial charge rate could exacerbate the problem.
Temperature sensing on the battery would reduce the voltage and hence
the charge rate thus saving the battery. I wasn't talking about deep
cycles at all.
I think that we got off on the wrong foot when I pointed out that AGMs
have shorter lifetimes in deep cycle service than do gell-cells. I
agree that deep cycle service is unusual in an aircraft except where
there is a failure and that is not normal operation. But I did want to
emphasize that there is confusion in people's minds between gell-cell
batteries and AGM batteries and that you need to adjust the charging
system to accommodate the type of battery you have installed in your
aircraft and the temperature at which that battery is operating.
One thing that *is* worth considering is that the difference between
charge and float voltages in gell-cell batteries are much closer
together than are the charge and float voltages for flooded-cell and AGM
batteries. If you are going to have a charging system with only a
single set-point, I think you may find that the gell-cell lives longer
than the AGM in that environment.
In my RV-4 I installed an over-sized gell-cell that would power my
e-buss for 4 hours, the normal fuel duration of the aircraft. I knew
that if I got to the end of the battery capacity, I probably had other,
more pressing problems to deal with. The point is that the bigger
gell-cell was able to crank the O-320 very happily thus validating the
"bigger battery means more current" philosophy.
And you may be right that the Odyssey battery is the be-all and end-all
of batteries. It may be so robustly constructed that it takes the abuse
without damage so all this may be a moot point.
But I still believe that one should operate all the devices in an
aircraft as conservatively as possible. It won't hurt your Odyssey
battery to perform a proper three-stage charge cutting off to the proper
float voltage, will it?
Pax?
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
==
==
==
==
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: engine hot starting |
George Braly wrote:
> Your technique is common for hot starts.
>
> It is not the technique that makes use of knowledge as to what the real
> problem is. And it is a technique that can be very dangerous and cause
> a fire that can and has consumed an airplane.
As for the technique:
1. it has been recommended by a number of respected sources;
2. it works.
OTOH, I defer to you. Certainly if anyone knows aircraft fuel injection systems,
you do.
> Until you sufficiently cool off the core of the fuel pump it will ALWAYS
> - - ALWAYS vapor lock.
Good point. This is a common problem with the O-540 in my carburated Comanche.
No reason the problem wouldn't also exist with the engine-driven fuel pump in
the IO-540.
> You either have to:
>
> 1) cool off the core of the engine driven fuel pump (easy with a TCM
> fuel system); or,
>
> 2) You have to use the electric boost pump to keep the engine running
> until the core of the engine driven pump does cool off enough to quit
> flashing the incoming fuel to vapor (typical Lycoming and some twin
> Cessna techniques).
Good point. I will leave the boost pump on in the flooded start procedure instead
of turning it off.
> After the fuel pump core components are cooled off, the engine will
> actually start better than when cold.
Unfortunately there is no good way to cool off the fuel pump in the Bendix RSA
injection system short of pouring fuel into the induction system.
So I am interested in a better way to start the engine. What suggestions do you
have?
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| Subject: | Alternator Failure |
| From: | "David Chalmers" <David(at)ChalmersFamily.com> |
Well today I had an alternator failure on a cross country. Luckily I had installed
Bob's low voltage warning light and it started flashing in front of me as
soon as the alternator failed. After landing and assessing the options I was able
to fly back to home base using just the battery and minimal equipment. Only
reason I felt confident doing this was because I have subscribed to Bob's advice
and change the battery every year so I knew what it was close to rated capacity.
Thanks Bob for your advice over the years - it paid off for me today. Without the
low voltage warning or the known-healthy battery I would have been stranded
in the middle of nowhere.
Dave Chalmers
Redmond, WA
________________________________________________________________________________
| Subject: | 3 stage voltage regulator |
| From: | Christopher J Fortin <cjfortin(at)juno.com> |
Hi Brian,
I was wondering if this regulator -Cruzpro SAR20- might be suitable for
use in a plane. You can get it for less than $140 here in the states.
http://www.cruzpro.com/sar20.html
Chris Fortin
N813CJ reserved
________________________________________________________________________________
| From: | "James Foerster" <jmfpublic(at)comcast.net> |
| Subject: | Re: Characterization of Westach 720-4a sensor |
Ira,
Why do you want to use a 4n25? This is a gallium-arsenide infrared diode driving
transistor in a six pin package, usually used as a signal isolator. This one
is good for 2500 volts. Since the coil of your transducer is already isolated,
I don't see why you took this path. I suspect that I am missing some information
about this problem that led you in this direction.
Brian Lloyd is right, of course, that an oscilloscope would directly measure your
voltage. I suspect that the impedance is about equal to the DC resistance
of the coil in the device. You could measure voltage open circuit with the scope,
then put a non-inductive resistor across the input and calculate the resistance
of the source knowing the reduced voltage with load.
Don't try to calculate your voltage. The change in reluctance in this circuit,
which gives the change in magnetic field (B field) is not linear ,as in your
calculation that the maximum velocity is 1000 inches per second. It is also not
sinusoidal, and thus not practical to calculate. Just use an amplifier which
has high gain, and it will make no difference. I'd try to use a comparator--op
amp designed to run open loop and output to the supply rails--but Bryan had
a more elegant solution. At the frequencies involved, either way would work.
I just searched the Westach site, and I can't find this particular unit. I had
hoped that they would have some suggested circuits for the sensor.
Jim Foerster
________________________________________________________________________________
| From: | "Trampas" <tstern(at)nc.rr.com> |
| Subject: | Characterization of Westach 720-4a sensor |
Check out the LM1815 chip from what you have described this chip will do
what you need.
http://www.national.com/pf/LM/LM1815.html
Regards,
Trampas
www.sterntech.com
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
irampil(at)notes.cc.sunysb.edu
Subject: AeroElectric-List: Characterization of Westach 720-4a sensor
Greetings,
Has anyone seen or developed a characterization of this tach sensor?
It is a combined magnet/coil combo used to generate a pulse when a
bit of iron speeds past(Ampere's law). In my case, I have 6 steel AN5
bolt
heads/revolution roughly 3/32" from the sensor head at roughly 1000
inches/sec max.
I'd like to know the expected output voltage and impedance so I can
compute the
input resistor for a 4n25. I need to divide the output pulse rate by 4
with a little TTL to
get it into the frequency range for my tachometer system.
Any advice?
Ira N224XS flying, but due for a little panel rework
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
>It is a combined magnet/coil combo used to generate a pulse when a
>bit of iron speeds past (Ampere's law).
Ira,
You should immediately contact a lawyer and bring a lawsuit against your
school.
The law you state is Faraday's Law.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones(at)charter.net
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: 3 stage voltage regulator |
Christopher J Fortin wrote:
>
> Hi Brian,
>
> I was wondering if this regulator -Cruzpro SAR20- might be suitable for
> use in a plane. You can get it for less than $140 here in the states.
> http://www.cruzpro.com/sar20.html
It looks like it will do what you want but I know nothing about CruzPro.
It is nice to see that you can program it for alternator size and battery size.
I would want to know how they use that information to determine the absorption
time. Sounds like it is time for a call to the company. Don't be surprised
if it is a one-person operation. On the plus side, the owner will probably
be willing to explain the system to you.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Characterization of Westach 720-4a sensor |
Trampas wrote:
>
> Check out the LM1815 chip from what you have described this chip will do
> what you need.
> http://www.national.com/pf/LM/LM1815.html
That is exactly what he needs. Wow, all that in one package. Who would'a guessed.
It has been a long time since I have poked through a Nat Semi catalog.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: Battery data and etc |
> Now that we have traded ideas and insults, may I buy you a beer at OSH so
we can discuss battery and charging technology at greater length?
>
> --
> Brian Lloyd
Well done
Paul
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Battery data and etc |
Paul Messinger wrote:
>
>>Now that we have traded ideas and insults, may I buy you a beer at OSH so
>
> we can discuss battery and charging technology at greater length?
>
>>--
>>Brian Lloyd
>
>
> Well done
Well, getting all pissy at each other doesn't really solve anything, does it.
Drinking beer after a day of flying or playing with airplanes is far more pleasant.
By the way, seems you got the BIG guns to wade in on your side of the engine starting
question. So are you going to share your starting procedure?
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: engine hot starting |
I agree with both of your statements.
>
> > The best system in my opinion is the one on the S35 and its so unique
its
> > got a special section in the A&P manual. One simple dual spool rotary
valve
> > and easy to use and dirt simple. Works all the time!
>
> It does have the advantage of being simpler than the Bendix RSA system but
it has no mechanism to prevent the engine from getting too rich to operate.
Leaving the boost pump in the high position can flood even a running engine.
Please read the book as there is NO hi or low boost on this system. Also
because there is a return line one can cycle fresh (cool) fuel thru the
system including the engine driven fuel pump. This reduces the amount of hot
fuel to vaporize when the mix is off idle cutoff.
Boost pump on is normal during airport ops and with no hi or low position no
worries of flooding. Again its the dirt simple system and simple worked
great for me for years.
Again its different from Lyc's of the time and also different from other
Bendix systems.
Been too long to remember exactly the procedure but as I recall its is
slightly different from what you said.
First full open throttle
mix to idle cutoff
Aux pump on (single speed pump) for several seconds to purge the fuel system
of hot fuel (the fuel not in the injecton lines)
Crank engine and when it fires close throttle and gradually move mix from
cutoff to rich. Not as hard as it seems.
The above avoids the totally flooded engine one gets with your procedure and
allows a faster start.
Not sure it would work with a setup where there was no fuel return line that
can be purged of hot fuel so you have a cold non flashing fuel supply going
into the injector lines.
> But I did want to emphasize that there is confusion in people's minds
between gell-cell batteries and AGM batteries and that you need to adjust
the charging system to accommodate the type of battery you have installed in
your aircraft and the temperature at which that battery is operating.
I agree and that may be one reason why Concord batteries seem to have a
shorter life in many aircraft with non adjustable regulators that are setup
for high voltage for fast recharging of the flooded type batteries.
>
> One thing that *is* worth considering is that the difference between
charge and float voltages in gell-cell batteries are much closer together
than are the charge and float voltages for flooded-cell and AGM batteries.
If you are going to have a charging system with only a single set-point, I
think you may find that the gell-cell lives longer than the AGM in that
environment.
My opinion from day one on this discussuon is NOT that proper care can make
the battery last longer but with the current common design what is
specifically the life. Frankly I do not need a 10 year battery and if I can
get 3-5 years with a current system why go to a lot of trouble and $$ for a
gain I do not need.
lots of corrent statementa abouut shortened life but shortened from to what.
10 years to 4?? 1000 flight hours to 200 This is what we all need to see if
your persomal flight habits need a differrent battery charging system.
I have a friend that recently sold his acft and he had a Optima (the round
one) Legally installed in his spam can. It was 6 years old and was working
just fine. He had a hard time starting the engine and ran it down on a
regulator basis and also had over 1000 hours on the battery. Stock regulator
non temp sensing etc. He saw no need for a different system.
Turns out, at least at that time, the 337 was approved as Optima had passed
and has available all the FAA requirements for an aircraft install and his
IA filled out the paper and thus it was legal.
Bottom line 6 years is longer than I would want to go between battery
replacements so why get fancy for a 10 year life.
>
>>
> And you may be right that the Odyssey battery is the be-all and end-all of
batteries. It may be so robustly constructed that it takes the abuse
without damage so all this may be a moot point.
I am not pushing Odyessy, but they only cost around double the Panasonic and
still well under $100 delivered and have the ability to sit around with NO
need for a float charger to keep it topped off like the Panasonic does.
>
> But I still believe that one should operate all the devices in an aircraft
as conservatively as possible. It won't hurt your Odyssey battery to
perform a proper three-stage charge cutting off to the proper float voltage,
will it?
Hurt, no but needed, I really do not think so. The standard constant Voltage
charge is very close to the first two stages. Hundreds of $$ and another
pound as well as several extra wires and a couple of fuses to install the
SAR 3 for questionable improvement over what I already get just seems to be
a unnecessary complexity.
Get a $50 adjustable reg and mount it near the battery (for temperature
compensation) and be done with it. Set the V on the low side of the range
and you are likely to get battery life that exceeds the reasonable battery
replacement cycle time.
As I said what is the improvement needed over 4-5 years?? I do not need any
longer life.
Use the proper low cost regulator and get both temp compensation and voltage
set for under $50. and no need for extra temp sensor.
The B&C reg is nearly $300 with the temp sensor option. lets see, 6X the
cost and no ability to adjust voltage. WHY go there?? The SAR 3 is even more
expensive for what. Longer than what life. Likely longer than I would ever
need but that is an individual decision. Bob suggests panasonic replacement
on an annual basis. This coupled with the average under 100 flight hours per
year makes sense to me.
So I have Odyssey batteries in the cabin and the reg is temperature
compensated V set type.
Two batteries and a regulator for around $200 total. Expected annual cost
$50 based on a biannual battery replacement.
Also I disagree with Bob's position on putting the fresh battery in the main
position. I want to know what the battery capacity is in an emengency so the
new battery is in the backup position. And yes I do load test annually as
that is so simple to do with NO extra equipment other than a clock :-)
Paul
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: engine hot starting |
Well said and I completely agree. Worked for me!
Paul
----- Original Message -----
From: "George Braly" <gwbraly(at)gami.com>
Subject: RE: AeroElectric-List: engine hot starting
>
>
> Brian,
>
> Your technique is common for hot starts.
>
> It is not the technique that makes use of knowledge as to what the real
> problem is. And it is a technique that can be very dangerous and cause
> a fire that can and has consumed an airplane.
>
> Getting fuel flow indications may indicate that "vapor is purged" - -
> but is not at all an indication that you are not going to vapor lock
> about 3-5 seconds after the engine fires up - - and then promptly stops.
>
> The reasons these engines are hard to start when HOT is very simple.
>
> The fuel pump core is HOT - - so hot that when new fuel hits the core of
> the engine driven fuel pump it flashes to vapor and vapor locks the
> inlet to the fuel pump.
>
> Until you sufficiently cool off the core of the fuel pump it will ALWAYS
> - - ALWAYS vapor lock.
>
> You either have to:
>
> 1) cool off the core of the engine driven fuel pump (easy with a TCM
> fuel system); or,
>
> 2) You have to use the electric boost pump to keep the engine running
> until the core of the engine driven pump does cool off enough to quit
> flashing the incoming fuel to vapor (typical Lycoming and some twin
> Cessna techniques).
>
> After the fuel pump core components are cooled off, the engine will
> actually start better than when cold.
>
> Regards, George
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Brian
> Lloyd
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: engine hot starting
>
>
> Paul Messinger wrote:
>
> > I do know 99% of owners have a heck of a time with hot starts and most
> say
> > they are using the acft manual procedure. Well I had problems with my
> Beech
> > hot starting until I forgot the manual and was told how to start just
> about
> > any brand or injected engine works every time and seldom more than a
> few
> > seconds.
>
> I agree that the hot-start technique usually provided in the pilot's
> handbook doesn't work very well. With Lycoming or Continental engines I
> find that the flooded start technique works quite well although it does
> require a bit of cranking. The technique I use is as follows:
>
> 1. Throttle and mixture full forward, i.e. full throttle and rich
> mixture.
>
> 2. Boost pump on until you see a stable fuel-flow indication. This
> means the vapor is purged from the system.
>
> 3. Mixture to idle-cut-off (ICO) and boost pump off.
>
> 4. Crank the engine.
>
> 5. When the engine fires, retard the throttle and advance the mixture.
>
> This technique works very reliably as the fuel lines and other
> components are cooled with fresh fuel and fuel vapor is purged from the
> lines. The problem now is that the engine is just about guaranteed to
> be flooded. Cranking with the throttle wide open admits the maximum
> amount of air and the mixture at ICO precludes any more fuel being
> admitted to the engine. As the engine cranks the mixture, which was
> initially too rich to fire, becomes progressively leaner until the
> engine fires. At that point the throttle is retarded and the mixture
> advanced to allow the engine to operate normally.
>
> >> It doesn't matter whether you think that the Lycoming injection
> system
> >> (actually Bendix RSA) is better or worse than Continental's (I happen
> to
> >> think it is better because it is a closed-loop servo system based on
> mass
> >> airflow measurement), the key point is that the problem I described
> CAN and
> >> DOES happen on a regular basis.
> >
> > I agree it happens on a regular basis but I disagree it needs to
> happen
> > nearly as often. I have yet to see the fool proof hot start procedure
> in any
> > manual.
>
> I agree with both of your statements.
>
> > The best system in my opinion is the one on the S35 and its so unique
> its
> > got a special section in the A&P manual. One simple dual spool rotary
> valve
> > and easy to use and dirt simple. Works all the time!
>
> It does have the advantage of being simpler than the Bendix RSA system
> but it has no mechanism to prevent the engine from getting too rich to
> operate. Leaving the boost pump in the high position can flood even a
> running engine.
>
> > The Cont systems I have personal experience have a fuel pump return
> line
> > back to the tank and the Lyc's have no return line. Thus not only is
> the
> > fuel in the low pressure injecton lines boiled off but the engine
> driven
> > pump heats its fuel and in the LYC case you cannot flush the hot fuel
> out so
> > those designs are designed to be harder to start.
>
> The "flooded start" procedure I outlined above works quite well but you
> may have to crank for 15 seconds or so depending on how much fuel you
> had to push through the injection system to purge the fuel vapor.
>
> I also like the fact that the Bendix fuel servo compensates for changes
> in fuel pressure and adjusts the flow accordingly. Also the mass
> airflow sensing causes the mixture to be more consistent as the aircraft
> changes altitude thus reducing cockpit workload for the pilot during
> climb and descent.
>
> Both systems work pretty well but they are very different. I do find it
> interesting to note that the popular modern aftermarket continuous-flow
> injection systems from Airflow Performance are based on the principles
> in the Bendix RSA system. The Bendix RSA fuel injection system is
> pretty old now and could use some updating but we all know how likely
> that is given the regulatory nature of the FAA. Bendix has no
> motivation to improve their system.
>
> >> In a perfect world, maybe. If you feed the engine the proper
> mixture, it
> >> will fire and run. In a hot start that can be difficult and many
> OBAM
> >> aircraft have very tight cowls that retain heat on the ground causing
> the
> >> entire fuel system to become heat-soaked. Ensuring the proper
> mixture then
> >> becomes a crap shoot. They can be a real bitch to hot-start even if
> you
> >> hold your tongue right and the airplane gods are on your side.
> >
> > See above My experience appears to differ
>
> Great! I am eager to learn. What is your technique? My technique
> works but I would much rather save the wear and tear on the starter and
> battery if possible.
>
> >> So perhaps you knew the magic incantation to make your engine start
> in three
> >> blades at all times but I think that the experience of the
> run-of-the-mill
> >> pilot will be different. I accept that it is possible that the pilot
> may
> >> have a period of extended cranking which will heat up and discharge
> the
> >> battery. That is the safest assumption and I prefer to design for
> that.
> >
> > So what and what is your point as the number of deep cycles in the
> battery
> > is small compared to the battery design if you choose the proper
> battery.
>
> If you recall, I was pointing out how a thermal runaway event in a
> battery could be initiated on a hot day with a prolonged cranking event
> and how a high initial charge rate could exacerbate the problem.
> Temperature sensing on the battery would reduce the voltage and hence
> the charge rate thus saving the battery. I wasn't talking about deep
> cycles at all.
>
> I think that we got off on the wrong foot when I pointed out that AGMs
> have shorter lifetimes in deep cycle service than do gell-cells. I
> agree that deep cycle service is unusual in an aircraft except where
> there is a failure and that is not normal operation. But I did want to
> emphasize that there is confusion in people's minds between gell-cell
> batteries and AGM batteries and that you need to adjust the charging
> system to accommodate the type of battery you have installed in your
> aircraft and the temperature at which that battery is operating.
>
> One thing that *is* worth considering is that the difference between
> charge and float voltages in gell-cell batteries are much closer
> together than are the charge and float voltages for flooded-cell and AGM
> batteries. If you are going to have a charging system with only a
> single set-point, I think you may find that the gell-cell lives longer
> than the AGM in that environment.
>
> In my RV-4 I installed an over-sized gell-cell that would power my
> e-buss for 4 hours, the normal fuel duration of the aircraft. I knew
> that if I got to the end of the battery capacity, I probably had other,
> more pressing problems to deal with. The point is that the bigger
> gell-cell was able to crank the O-320 very happily thus validating the
> "bigger battery means more current" philosophy.
>
> And you may be right that the Odyssey battery is the be-all and end-all
> of batteries. It may be so robustly constructed that it takes the abuse
> without damage so all this may be a moot point.
>
> But I still believe that one should operate all the devices in an
> aircraft as conservatively as possible. It won't hurt your Odyssey
> battery to perform a proper three-stage charge cutting off to the proper
> float voltage, will it?
>
> Pax?
>
> --
> Brian Lloyd 6501 Red Hook Plaza
> brianl(at)lloyd.com Suite 201
> http://www.lloyd.com St. Thomas, VI 00802
> +1.340.998.9447 (voice) +1.360.838.9669 (fax)
>
> There is a time to laud one's country and a time to protest.
> A good citizen is prepared to do either as the need arises.
>
>
> ==
> ==
> ==
> ==
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: AeroElectric-List off track???? |
>Comments/Questions: Bob,
>
>Sending this to you off list as I don't want to be seen as unappreciative
>of others well meant efforts.
>I took your seminar a couple of years ago at Watsonville and have been a
>happy lurker on the list ever since, learning as I go until I come to do
>my electrical system. Maybe it's just me but it seems like the tone of the
>aeroelectric list has changed in the past couple of months from a fun to
>read and informative list that explained things in terms my electronically
>challenged mind could understand. It now seems we have a couple of
>engineers (no disrespect intended !!) using the list to prove and disprove
>stuff that frankly I don't understand and don't think I need to understand.
Understand. I'm going to echo this to the list and strip
of your name because while your comments and frustration
are understandable, there are very good reasons for this
condition. Further, it's a situation over which YOU and
all other lurkers have a great deal of control.
>I've now taken to simply deleting most of their messages unread, which is
>a shame because there's probably a lot of things they could teach, but not
>with the same good grace and patience you've exhibited. Basically they
>seem to have monopolized the list and although I'm sure they have lots of
>experience and knowledge to offer frankly their style is somewhat
>intimidating to us amateurs.
>
>Not sure there's much if anything you can or should do and perhaps I'm off
>base etc and out of line. Just thought my perspective may be of interest.
Folks who are members of the OBAM aircraft community
are a diverse collection of individuals with huge
variability in interests, skills, knowledge and motivations.
I suspect that a majority of our brethren have interests
pretty much in line with your own . . . let's get this
airplane done with a minimum of effort and maximize return
on investment for time invested to achieve utility and
performance in an airplane.
At the same time there are folks who have an interest
in supplying products. I have an information gathering and
dissemination activity and sell a few fabricated products.
Others have no interest at all in building or owning an aircraft but
they're really good at gathering, organizing, advertising
and providing parts procurement services.
Irrespective of your (or anyone else's) motivations, there
is an underlying foundation common to the success of everyone's
goals in this community. The discovery, understanding and
practical application of simple ideas. Doesn't matter if you're
struggling over the selection of a screw and wire-bundle clamp
or mitigating probability of a gremlin of some variety spiking
your $high$ radio. Once you've peeled back all the myths,
misunderstandings and/or marketing hype, the ANSWER IS ALWAYS
STONE SIMPLE and easy to UNDERSTAND.
When things don't perform as desired and a modification of
materials and techniques are called for, the ANSWER IS
ALWAYS STONE SIMPLE and easy to UNDERSTAND.
>Appreciate you sharing your experience over the years.
Thank you. I'm pleased that you find my contributions useful.
However, pleased keep in mind that the AeroElectric-List
was established for the same reasons as the Aero-Electric
Connection book. . . to be a forum and gathering place for the
best we know how to do. Just yesterday I was wrapping up
a weekend seminar in Long Beach and made the comment that
while I write and edit the 'Connection, it's not MY book.
Its creation and content is totally driven by the participation
of folks who participate in the discussions that precede the
publication of words. It's not practical or useful for me
to write about everything I've learned in the past 40
years . . . it's best to write when I can contribute to
mitigation of YOUR questions in a quest of a achieving
YOUR goals.
The 'Connection came into existence about 1988 base on
my perceptions of need. I'd spent a week at OSH answering
questions out of B&C's booth. My perception was that the
electrical system was the least understood system on the airplane.
The following year, the first few chapter were published and
the plan is to continue to grow it even after all these years.
However, it SHOULD grow based on your questions are and
not on what this guy Bob Nuckolls thinks you should know.
The 'List is exactly the same. The List SHOULD be (and in
fact IS) exactly what you and other participants make it.
I'll grant you that there will be times when some of the
List's techno-nerds stir a pot of ideas where you'd rather
wait until the final paragraph is published before you read it.
But please keep in mind that this is YOUR list. If the
conversations are short on topics of interest to you, it's
only because you've not asked any questions about those
topics. I nor anyone else on the list should take on the
responsibility for moderating or otherwise driving the
direction of conversation on the list. This isn't the
kindergarten of aviation technology and skills . . . it's
a graduate course where we all have duties of participation.
I've avoided invoking suggestions in Matt's missives on
"proper use of the AeroElectric-List" when conversations
might appear to be off-topic. I personally welcome ANY
discussion that goes to the discovery and application of
simple ideas whether or not they're germane to electrical
systems or avionics.
When I or anyone else seems to dominate the list
with discussions centered in our favorite OBAM aircraft
discipline, that perception of dominance is driven
only by an unwillingness of others to accommodate their own
interests right along with everyone else.
It would be a really great thing if the 'Connection and
the 'List were core data sources for 95% of the OBAM aircraft
under construction . . . but it isn't going to happen.
I believe there are a relatively few numbers of builders
at the top of the bell-curve that quest for useful, simple-
ideas. It's those folks who are pushing the state of our
art forward. The rest are simple consumers . . . which
is perfectly fine. They too contribute to the gross numbers
of aircraft that make our hobby a significant force in
aviation.
So my friend, I'd like to believe that you have properly
positioned yourself in the OBAM community membership who
map at the top of the bell-curve in a quest for knowledge.
So, how may I or anyone else on the List be of service
to you today?
Bob . . .
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | engine hot starting and more on batteries |
Paul Messinger wrote:
> Please read the book as there is NO hi or low boost on this system.
It has been a long time since I have flown behind a big Continental but I do remember
the hi/lo boost pump. You say they did away with it?
> Also
> because there is a return line one can cycle fresh (cool) fuel thru the
> system including the engine driven fuel pump. This reduces the amount of hot
> fuel to vaporize when the mix is off idle cutoff.
That is a definite win.
> Boost pump on is normal during airport ops and with no hi or low position no
> worries of flooding. Again its the dirt simple system and simple worked
> great for me for years.
Then where did I get the idea there is a high/low boost pump? I am sure it was
from Continental engines. The Bendix RSA injection system has only on/off for
the boost pump.
> Again its different from Lyc's of the time and also different from other
> Bendix systems.
OK.
> Been too long to remember exactly the procedure but as I recall its is
> slightly different from what you said.
>
> First full open throttle
> mix to idle cutoff
> Aux pump on (single speed pump) for several seconds to purge the fuel system
> of hot fuel (the fuel not in the injecton lines)
>
> Crank engine and when it fires close throttle and gradually move mix from
> cutoff to rich. Not as hard as it seems.
>
> The above avoids the totally flooded engine one gets with your procedure and
> allows a faster start.
That sounds a lot like the start procedure listed in the aircraft manual. It does
not work well for the Lyc IO-540 in the Aztec. The fuel in the injector lines
and the flow divider is already vaporized.
> Not sure it would work with a setup where there was no fuel return line that
> can be purged of hot fuel so you have a cold non flashing fuel supply going
> into the injector lines.
Right. That is the Achilles heel of the Bendix RSA system. Maybe George Braly
will answer my question. If anyone knows how to deal with these injected engines,
it is him. (For those who don't know, George Braly is the head engineer
for GAMI.)
>> But I did want to emphasize that there is confusion in people's minds
>> between gell-cell batteries and AGM batteries and that you need to adjust
>> the charging system to accommodate the type of battery you have installed in
>> your aircraft and the temperature at which that battery is operating.
>
> I agree and that may be one reason why Concord batteries seem to have a
> shorter life in many aircraft with non adjustable regulators that are setup
> for high voltage for fast recharging of the flooded type batteries.
I agree with that. Going back to the Deka white paper on their sealed batteries
(the following is a quote from page 12):
"If the right pressure (voltage) is used for the temperature, a battery will accept
charge at its ideal rate. If too much pressure is used, charge will be forced
through the battery faster than it can be stored. Reactions other than the
charging reaction occur to transport this current through the battery -- mainly
gassing. Hydrogen and oxygen are given off faster than the recombination reaction.
This raises the pressure until the pressure relief valve opens. The gas
lost cannot be replaced. Any VRLA battery will dry out and fail prematurely
if it experiences excessive overcharge.
Note: It is the pressure (voltage) that initiates this problem -- a battery can
be over-charged (damaged by too much voltage) even though it is not fully charged.
This is why charging voltage must be carefully regulated and temperature compensated
to the values on page 11."
To me, this argues very persuasively for proper temperature compensation.
>>One thing that *is* worth considering is that the difference between
>> charge and float voltages in gell-cell batteries are much closer together
>> than are the charge and float voltages for flooded-cell and AGM batteries.
>> If you are going to have a charging system with only a single set-point, I
>> think you may find that the gell-cell lives longer than the AGM in that
>> environment.
>
> My opinion from day one on this discussuon is NOT that proper care can make
> the battery last longer but with the current common design what is
> specifically the life. Frankly I do not need a 10 year battery and if I can
> get 3-5 years with a current system why go to a lot of trouble and $$ for a
> gain I do not need.
>
> lots of corrent statementa abouut shortened life but shortened from to what.
> 10 years to 4?? 1000 flight hours to 200 This is what we all need to see if
> your persomal flight habits need a differrent battery charging system.
Perhaps you are right. OTOH, I have experienced early battery failure. The best
case is that you end up stuck at some unknown airport trying to buy a new battery
or get a jump start. Worst case is that the alternator fails and you watch
your battery go flat in a few minutes. Flying IFR with a flashlight stuck
in your mouth while using a handheld comm and a handheld GPS to navigate doesn't
strike me as particularly fun.
It doesn't strike me as being all that hard to ensure a proper battery charge so
that the battery will be in good shape should you need it to carry your endurance
loads. As Chris Fortin found, there are three-stage charge controllers
available for very reasonable prices. If you can get a good temperature-compensated
three-stage regulator for $140, why not? Your battery will be happier
and maybe you will find that your battery will truly last 5 years.
When you abuse your battery you shorten its life. Now its life isn't some absolute
number like 5 years, battery failures will average out to be something like
5 years, with some lasting longer and some having shorter lives. When you
abuse the battery you reduce that time and perhaps greatly increase the incidence
of total failure at an early age (as I did with the Concorde AGMs). Even
if I decide I am going to get a new battery every one or two years, doesn't it
make sense that I treat it well so that the chance of early failure is as low
as possible?
> I have a friend that recently sold his acft and he had a Optima (the round
> one) Legally installed in his spam can. It was 6 years old and was working
> just fine. He had a hard time starting the engine and ran it down on a
> regulator basis and also had over 1000 hours on the battery. Stock regulator
> non temp sensing etc. He saw no need for a different system.
Lucky him.
> Turns out, at least at that time, the 337 was approved as Optima had passed
> and has available all the FAA requirements for an aircraft install and his
> IA filled out the paper and thus it was legal.
That is certainly nice. I will consider that when it comes time to change the
battery again. This kind of thing is much more important in Spam cans where you
don't get the option of building a really good electrical system such as we
do with OBAM and other experimental aircraft.
> Bottom line 6 years is longer than I would want to go between battery
> replacements so why get fancy for a 10 year life.
That is fine. Now I am interested in reducing early failures to zero.
>>And you may be right that the Odyssey battery is the be-all and end-all of
>> batteries. It may be so robustly constructed that it takes the abuse
>> without damage so all this may be a moot point.
>
> I am not pushing Odyessy, but they only cost around double the Panasonic and
> still well under $100 delivered and have the ability to sit around with NO
> need for a float charger to keep it topped off like the Panasonic does.
All batteries have some level of self discharge. The lead alloy can reduce that
to some extent but you can't eliminate that. The warmer the battery, the faster
the level of self discharge. Keeping a battery on a proper float charge
is a safe thing to do. YMMV.
>>But I still believe that one should operate all the devices in an aircraft
>> as conservatively as possible. It won't hurt your Odyssey battery to
>> perform a proper three-stage charge cutting off to the proper float voltage,
>> will it?
>
> Hurt, no but needed, I really do not think so. The standard constant Voltage
> charge is very close to the first two stages. Hundreds of $$ and another
> pound as well as several extra wires and a couple of fuses to install the
> SAR 3 for questionable improvement over what I already get just seems to be
> a unnecessary complexity.
Certainly the SAR-3 from Ample Power is overkill. The dual-display EFIS-1 from
Blue Mountain is too but I am putting it in nonetheless. A Garmin 530 is too.
There is no added complexity as it wires up the same way an automotive VR does
(with the exception of the temp sensor).
> Get a $50 adjustable reg and mount it near the battery (for temperature
> compensation) and be done with it. Set the V on the low side of the range
> and you are likely to get battery life that exceeds the reasonable battery
> replacement cycle time.
I don't completely agree with this as the battery may be at a different temperature
than its surroundings. The only way to measure battery temperature for sure
is to actually attach the measuring device to the battery. Remember that
the battery is going to get warm during charge and it is going to be warmer than
the surrounding air. Who knows what the current through the VR is going to
do to the temperature of the VR. I can safely say that the two of them will
*NOT* be at the same temperature unless the VR is firmly attached to the battery.
Also, what is the temperature compensation curve in these cheap regulators? Does
it match what the battery requires? I think not. I bet it is just something
like a reduced voltage drop across a couple of diodes in the VR reference circuit,
not exactly tailored to the voltage settings required for a proper battery
charge.
> As I said what is the improvement needed over 4-5 years?? I do not need any
> longer life.
But I want higher reliability and less chance of initial failure in the time that
I do keep my battery, even if it is only two years.
> Use the proper low cost regulator and get both temp compensation and voltage
> set for under $50. and no need for extra temp sensor.
Again, I don't believe that will work.
> The B&C reg is nearly $300 with the temp sensor option. lets see, 6X the
> cost and no ability to adjust voltage. WHY go there?? The SAR 3 is even more
> expensive for what. Longer than what life. Likely longer than I would ever
> need but that is an individual decision. Bob suggests panasonic replacement
> on an annual basis. This coupled with the average under 100 flight hours per
> year makes sense to me.
>
> So I have Odyssey batteries in the cabin and the reg is temperature
> compensated V set type.
>
> Two batteries and a regulator for around $200 total. Expected annual cost
> $50 based on a biannual battery replacement.
Certainly that is a way to go. But now many people on this list now have a better
idea how all this works and can make a choice for themselves? How many people
on this list are building beautiful works of mechanical art and want to do
everything as perfectly as possible? Achieving perfection even in the small
things can be a reward in and of itself. Please don't run that down.
> Also I disagree with Bob's position on putting the fresh battery in the main
> position. I want to know what the battery capacity is in an emengency so the
> new battery is in the backup position. And yes I do load test annually as
> that is so simple to do with NO extra equipment other than a clock :-)
Perhaps. OTOH, it is the main battery that gets all the use.
I also think that it is a good idea to deep cycle the battery at least once to
see what its real capacity is. Then I can put it in the airplane knowing what
it will *really* do.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: engine hot starting and more on batteries |
In a message dated 6/21/04 10:42:21 AM Central Daylight Time,
brianl(at)lloyd.com writes:
It has been a long time since I have flown behind a big Continental but I do
remember the hi/lo boost pump. You say they did away with it?
Good Morning Brian,
Let us not say they have done away with it, just that it has come and gone,
then come back again often depending on the perceived need.
In almost all cases where there is a high and low position of the boost pump
used in a Continental powered Bonanza, or derivative, aircraft, the low
position is just a switch contact which runs the current through an appropriately
sized resistor. Same pump, no big deal.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Airpark LL22
Downers Grove, IL 60516
630 985-8502
________________________________________________________________________________
| From: | Mickey Coggins <mick-matronics(at)rv8.ch> |
| Subject: | Serial vs. Parallel altitude encoders |
Hi,
I've purchased a narco AT 155 transponder, and it
requires a parallel altitude encoder. When I bought
it at SNF the encoder I planned to use (Dynon) provided
a parallel output. Now, their new model only provides
serial output. I guess my options are to change
my transponder, buy a different encoder, buy the old
model of Dynon, or get a box to do a conversion.
Any words of wisdom from the group on this?
Thanks,
Mickey
--
Mickey Coggins
http://www.rv8.ch/
#82007 QB Wings/Fuselage
________________________________________________________________________________
| From: | "Jim Butcher" <europa(at)triton.net> |
| Subject: | Re: Characterization of Westach 720-4a sensor |
Ira,
Greg at BMA has suggested to me that I use a BMA current senser (Hall
effect) to measure the pulses Rotax generates for the electric tach.
Haven't tried it yet, but this summer for sure.
Jim Butcher Europa A185
________________________________________________________________________________
| From: | "Steve Richard" <steve(at)oasissolutions.com> |
| Subject: | engine hot starting and more on batteries |
Just another data point:
I have a Continental TSIO-520 in a Mooney. I had difficulty starting it
when hot until I talked to a ex-Mooney test pilot (he writes for one of the
Mooney mags now). He told me the problem with Cont. is fuel starvation. He
also told me that the primer button puts fuel in the 'manifold' and the
low/high buttons put fuel in the injectors. I was trying to hot start using
the primer button. He told me I would never get enough fuel in the
cylinders to get thing going.
His hot start method:
All controls full forward
Hi boost for 2-3 seconds.
Throttle to 3/4" forward of closed.
Crank (Momentary pushes on low boost to help things along)
Can't vouch for the fuel layout described above but it works every time.
Steve Richard
steve(at)oasissolutions.com
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
BobsV35B(at)aol.com
Subject: Re: AeroElectric-List: engine hot starting and more on
batteries
In a message dated 6/21/04 10:42:21 AM Central Daylight Time,
brianl(at)lloyd.com writes:
It has been a long time since I have flown behind a big Continental but I
do
remember the hi/lo boost pump. You say they did away with it?
Good Morning Brian,
Let us not say they have done away with it, just that it has come and gone,
then come back again often depending on the perceived need.
In almost all cases where there is a high and low position of the boost
pump
used in a Continental powered Bonanza, or derivative, aircraft, the low
position is just a switch contact which runs the current through an
appropriately
sized resistor. Same pump, no big deal.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Airpark LL22
Downers Grove, IL 60516
630 985-8502
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | private manned space flight |
Scaled Composite's "Space Ship 1" completed a successful manned-flight to 100Km
this morning. Looks like they are well on the way to winning the X-prize.
Wow, when I heard of the X-prize several years ago I was skeptical. Burt Rutan
does it again!
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| Subject: | Automotive Landing Lights? |
| From: | "Bordelon, Greg" <gbordelon(at)hess.com> |
I want to add more landing/taxi lighting to my aircraft. I went down to
Pep Boys and purchased several auto headlights, driving lights, and fog
lights. I conducted some experiments at night and found there is huge
difference in illumination pattern among the lights I purchased. I also
found that using a combination high & low beam head light worked very
well when BOTH elements were turned on. Anyone on the list have any
experience using high/low beam simultaneously? I'm a bit concerned that
having both elements glowing will significantly shorten the life of the
bulb to only a few hours. Any experiences out there? Thx
________________________________________________________________________________
| From: | "Larry McFarland" <larrymc(at)qconline.com> |
Hi guys,
On advice, I began the task of progressively redoing tie-ties that have put both
singular or grouped wires directly against metal. This typically required cutting
one and replacing it with 3 tie-ties to make two grips and a standoff.
It looked good, but seems to offer more motion to the wires thru engine vibration
acting against the wires. One has to consider which is worse, "movement
and fatigue" or "wear by tie-tie clamping wires against a surface and cutting
insulation". I've not seen much discussion of this on the Matronics pages.
If there are opinions or "rules" on these considerations beyond the usual Adel
clamps, etc
I'd be interested to hear about this area where wires traverse the smooth boundarys
of the motor mount and firewall.
Larry McFarland - 601HDS
________________________________________________________________________________
| From: | "Terry Watson" <terry(at)tcwatson.com> |
Along the same lines, I have been wondering about using short lengths of
vinyl tubing to pad the wires from the plastic wire ties. It's easy to do.
Just cut a short length, split it lengthwise, and put it around the bundle
of wires.
Terry
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Larry
McFarland
Subject: AeroElectric-List: wiring security
Hi guys,
On advice, I began the task of progressively redoing tie-ties that have put
both singular or grouped wires directly against metal. This typically
required cutting one and replacing it with 3 tie-ties to make two grips and
a standoff. It looked good, but seems to offer more motion to the wires
thru engine vibration acting against the wires. One has to consider which
is worse, "movement and fatigue" or "wear by tie-tie clamping wires against
a surface and cutting insulation". I've not seen much discussion of this on
the Matronics pages.
If there are opinions or "rules" on these considerations beyond the usual
Adel clamps, etc
I'd be interested to hear about this area where wires traverse the smooth
boundarys of the motor mount and firewall.
Larry McFarland - 601HDS
________________________________________________________________________________
| From: | Benford2(at)aol.com |
| Subject: | Re: Automotive Landing Lights? |
In a message dated 6/21/2004 4:02:42 PM Mountain Daylight Time,
gbordelon(at)hess.com writes:
>
> I want to add more landing/taxi lighting to my aircraft. I went down to
> Pep Boys and purchased several auto headlights, driving lights, and fog
> lights. I conducted some experiments at night and found there is huge
> difference in illumination pattern among the lights I purchased. I also
> found that using a combination high & low beam head light worked very
> well when BOTH elements were turned on. Anyone on the list have any
> experience using high/low beam simultaneously? I'm a bit concerned that
> having both elements glowing will significantly shorten the life of the
> bulb to only a few hours. Any experiences out there? Thx
Naw. The bulb will last a long time but you will be pulling some serious amps
to run them both at the same time. You want to use spot bulbs for the landing
light and fog/driving lights for taxi lights. All ya got to do is look at the
lens, that determines the light pattern.
Ben Haas N801BH.
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: engine hot starting and more on batteries |
----- Original Message -----
From: "Brian Lloyd" <brianl(at)lloyd.com>
> > I am not pushing Odyessy, but they only cost around double the Panasonic
and
> > still well under $100 delivered and have the ability to sit around with
NO
> > need for a float charger to keep it topped off like the Panasonic does.
>
> All batteries have some level of self discharge. The lead alloy can
reduce that to some extent but you can't eliminate that. The warmer the
battery, the faster the level of self discharge. Keeping a battery on a
proper float charge is a safe thing to do. YMMV.
Look at the self discharg times for the Panasonic vs the good ones. Sure
its temp dependent but we are looking at nearly a order of magnitude lower
self discharge rate; one that eleminates in most cases, any need for battery
float chargers that the Panasonic types require.
At 25C and 12 months the panasonic has LOST 36% of its charge. Odyssey
states at 25C it can be stored for 2 YEARS before needinmg to be recharged.
I do not remember the data on the Optima but its at least a year.
I did a test on one of my Odyssey batterys and it needed 15 min at one amp
after 9 months to tpo off using their recommended charger. The next day the
battery indicated 100% charge per their resting V table using a 0.025%
accurate meter.
A Panasonic needed over 12 hours to fully charge with the same charger etc.
Not needing to use a float charger is nice! WHY do it if its not required
and really does nothing much. Warm feeling a suppose :-)
>> > Get a $50 adjustable reg and mount it near the battery (for temperature
> > compensation) and be done with it. Set the V on the low side of the
range
> > and you are likely to get battery life that exceeds the reasonable
battery
> > replacement cycle time.
>
> I don't completely agree with this as the battery may be at a different
temperature than its surroundings. The only way to measure battery
temperature for sure is to actually attach the measuring device to the
battery. Remember that the battery is going to get warm during charge and
it is going to be warmer than the surrounding air. Who knows what the
current through the VR is going to do to the temperature of the VR. I can
safely say that the two of them will *NOT* be at the same temperature unless
the VR is firmly attached to the battery.
How close do you need to be??? Panasonic suggests its a large temp diff is
only a small gain in battery life. 30 deg c increases life 5%.
>
> Also, what is the temperature compensation curve in these cheap
regulators? Does it match what the battery requires? I think not. I bet
it is just something like a reduced voltage drop across a couple of diodes
in the VR reference circuit, not exactly tailored to the voltage settings
required for a proper battery charge.
Sorry but you need to do your homework on this one. The regulator chip is
specially designed to match closely the average battery temp vs V
requirements.
One key feature of the regulators is the ability to match the voltage needs
VS temp.
If it bothers you so much use heat sink compound and mount the reg to the
side of the battery :-)
> > Use the proper low cost regulator and get both temp compensation and
voltage
> > set for under $50. and no need for extra temp sensor.
>
> Again, I don't believe that will work.
Thats your opinion and you have every right to it.
> > The B&C reg is nearly $300 with the temp sensor option. lets see, 6X the
> > cost and no ability to adjust voltage. WHY go there?? The SAR 3 is even
more
> > expensive for what. Longer than what life. Likely longer than I would
ever
> > need but that is an individual decision. Bob suggests panasonic
replacement
> > on an annual basis. This coupled with the average under 100 flight hours
per
> > year makes sense to me.
> >
> > So I have Odyssey batteries in the cabin and the reg is temperature
> > compensated V set type.
> >
> > Two batteries and a regulator for around $200 total. Expected annual
cost
> > $50 based on a biannual battery replacement.
>
> Certainly that is a way to go. But now many people on this list now have
a better idea how all this works and can make a choice for themselves? How
many people on this list are building beautiful works of mechanical art and
want to do everything as perfectly as possible? Achieving perfection even
in the small things can be a reward in and of itself. Please don't run that
down.
Yes, but for the Nth time you have failed to respond with ANY facts in
regard to how much longer or how much better. Longer and better are not
enough for ANY informed decision. If it makes a 8 year battery into a 10
year one I could care less. If it makes a 3 year battery into a 1/2 year
battery I am interested. I suspect its the former and demonstrability not
the latter.
> > Also I disagree with Bob's position on putting the fresh battery in the
main
> > position. I want to know what the battery capacity is in an emengency so
the
> > new battery is in the backup position. And yes I do load test annually
as
> > that is so simple to do with NO extra equipment other than a clock :-)
>
> Perhaps. OTOH, it is the main battery that gets all the use.
Yes and if the backup battery has "lost its will to live" and lets you down
when you need it, what then. A backup is worse than useless if its not
reliable. MY position is if its not good enough for prime time its not
anything I want as backup. This is a general comment but in my case the
backup is really in use all the time as I have a electrically dependent
engine and both systems must be on and ready for instant prime time. Some
what different than mag powered VFR day flying.
Paul
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: Battery data and etc |
----- Original Message -----
From: "Brian Lloyd" <brianl(at)lloyd.com>
Subject: Re: AeroElectric-List: Battery data and etc
>
> Paul Messinger wrote:
>
> >
> >>Now that we have traded ideas and insults, may I buy you a beer at OSH
so
> >
> > we can discuss battery and charging technology at greater length?
> >
> >>--
> >>Brian Lloyd
> >
> >
> > Well done
>
> Well, getting all pissy at each other doesn't really solve anything, does
it. Drinking beer after a day of flying or playing with airplanes is far
more pleasant.
I Guess I cannot win no matter what I do.
I was being complimentary to your nice reply.
Paul
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Cont VS Bendix injection systems |
I can hardly ask others to be specific when I am not; so here are the
details on the two specific injection systems and why one is so much better
in hot starting.
This from a 1971 version of the A&P Powerplant Handbook.
I recognize that not all, in fact most (many?) Cont engines used the Bendix
system.
My S35 used the Cont system :-)
My MK21 Exec had the Bendix system :-(
First the basics of each system. I am paraphrasing the book.
The Bendix RSA system.
It uses a venturi/regulator setup to measure both the ram air pressure and
venturi suction with a somewhat complex dual diaphram ball valve assy to
meter fuel.
(The presence of the venturi leads to slightly lower manifold pressure and
slightly more possibility of induction system iceing .)
The metered and unmetered fuel is then sent to the Fuel metering section
where the Throttle linkage and mixture linkage combine in a metering assy.
From there the fuel is sent to the Flow divider usually at the top center of
the engine case where small lines radiate out to each cyl. The fuel in these
lines go thru a flow restrictor (small hole) and into the Cyl head.
From the fuel pump on, there is no vapor or fuel return line back to the
tank.
The system pressure is low to medium (compared to the modern auto injected
engine) between the Inlet Regulator assy to the Fuel metering section and
essentially zero when there is no flow (engine stopped) in the small feed
lines. It's the small feed lines that boil and flood into the cyl causing
excess fuel before the Hot start is attempted. From the inlet regulator
section to the distribution section the fuel is hot and ready to vaporize if
the pressure is low enough. With no way to replace this fuel the hot start
adds more fuel and vapor to an already too rich mixture and the hot start
attampt continues until all this hot fuel is purged.
But the engine compartment is hot and the fuel in the engine compartment has
no way to be replaced and thus must be purged thru the system with cool fuel
before reliable starting can occur. Thus the sometimes long process of
getting a start under hot conditions.
The Cont system, at least as described in the ref manual and on my S35 acft
(Cont IO520B)
Very differnt concept.
The engine driven pump is a Positive displacement pump and is able to use an
Aux pump with no change in performance. (no concern about HI or LOW pump
setting or changes in mixture with aux on or off)
The pump output pressure is independent of altitude or ambient air
conditions.
The pump has a built in bypass as well as a builtin Vapor seperator and fuel
return to the tank requirement. The aux pump can flush and replace hot fuel
with cool fuel.
The Fuel air control unit contains the throttle assy and NO venturi or other
air flow restrictions. (Slightly lower risk of icing and slightly higher
manifold pressure)
The fuel control assy has two series connected spool valves. One is linkled
to the throttle linkage and one to the mixture control. Excess fuel is
returned to the fuel pump and fuel is passed thru this assy even when the
mixture is in idle cutoff. This permits the aux pump to flush hot fuel all
the way to the output of this assy.
Finally there is the flow divider unit which is essentially the same as the
Bendix system.
Conclusions:
Bendix system cannot flush the fuel past the firewall as there is no fuel
return setup. In a hot start condition a significant amount of fuel must be
purged from the system and out the exhaust before the engine can run.
In the Cont system the aux pump can purge all the fuel except the small
amount in the line to and the lines from the flow divider. This is estimated
to be 80% or more of the total fuel in the engine compartment (there is
really only a very small amount of fuel in the non purgable part of the
system). Thus the Cont design greatly reduces the amount of hot fuel that
must be disposed of in a hot start.
I have extensive experience in the two systems and I would never, by choice
fly witrh an engine, using the Bendix system or at least as described above.
The MK21 was on occasion nearly imposable to hot start and the S35 was a
dream and easy to hot start.
In flight; I found leaning etc on climb etc (in single pilot IFR) no more
effort in either case. Both started cold equally well.
Hot start problems made the Bendix system unacceptable to me.
I sometimes wonder why so many just assume its part of the beast and do not
rise up and insist it be fixed.
Having experenced both I cannot understand how its put up with.
Paul
________________________________________________________________________________
| Subject: | King KSG100 slaved Gyro |
| From: | james.k.glindemann(at)exxonmobil.com |
7, 2002) at 06/22/2004 12:46:03 AM
I have acquired a King Directional Gyro Model No KSG100 and need the
connector pin out information. Does anybody out there have it?
thanks
James K Glindemann
________________________________________________________________________________
| From: | "Gary Casey" <glcasey(at)adelphia.net> |
| Subject: | Re: Cont VS Bendix injection systems |
I feel the need to comment on some of Paul's observations regarding the
Continental vs. "Bendix" fuel injection systems. There is no electrical
content here, so pardon us:
<>
I believe the opposite is true - the fuel flow in the Bendix system is
independent of inlet pressure until it is insufficient for full flow (about
15 psi), while the flow in the Continental system is sensitive to inlet
pressure and there have been accidents caused by the pilot incorrectly
choosing between high and low boost pump settings. In fact, if the mixture
is observed to change when the boost pump is turned on it should be
considered a defect. One important difference - the fuel flow rate in the
Continental system is also independent of another thing - the air flow into
the engine. The fuel flow in the Bendix system is inherently proportional
to air flow and independent of engine speed and inlet pressure. The
Continental system (unless the altitude-compensated version is used) does
not compensate for air density, while the fuel flow in the Bendix system is
proportional to the square root of inlet air density, essentially half
correcting for altitude and inlet air temperature. And the idle fuel flow
control is essentially the same in both systems, being a function of
throttle position, not air flow.
<>
True, except that the Continental system doesn't purge fuel all the way to
the spider, but to the fuel control valve. The Bendix system relies on
pressure being maintained between the pump and within the fuel control servo
to prevent boiling in that area. If the pressure bleeds off after shutdown
there is a problem in the fuel pump that should be corrected. And hot fuel
doesn't cause the problem - it is the fuel vapor that is the issue. In both
systems it can be assumed that all the fuel in the spider is boiled out, and
the residual fuel from the distributor back to the fuel control valve may or
may not be partially vapor.
And I think Paul mistyped - all Continental engines have the Continental
system except for those where the customer insisted on the Bendix system (I
think the Beech Duke is one of those). I don't know of a single case where
a Lycoming buyer selected the Continental system even though the Bendix
system, now manufactured by Precision Airmotive, has no corporate ties to
Lycoming. Yes, the venturi in the Bendix system does cause a manifold
pressure drop, but I don't know of any data that shows the system is more
prone to icing because of it.
<>
While the hot starting issue may be an area where the Continental has an
advantage, I don't think there have been any fatalities caused by hot start
problems. There have been fatalities caused by improper boost pump
operation in aircraft equipped with the Continental system. That, and the
fact that the Bendix system is at least partially compensated for air
density, are the reasons I prefer the Bendix system.
Gary Casey
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: engine hot starting and more on batteries |
Paul Messinger wrote:
> At 25C and 12 months the panasonic has LOST 36% of its charge. Odyssey
> states at 25C it can be stored for 2 YEARS before needinmg to be recharged.
> I do not remember the data on the Optima but its at least a year.
>
> I did a test on one of my Odyssey batterys and it needed 15 min at one amp
> after 9 months to tpo off using their recommended charger. The next day the
> battery indicated 100% charge per their resting V table using a 0.025%
> accurate meter.
>
> A Panasonic needed over 12 hours to fully charge with the same charger etc.
>
> Not needing to use a float charger is nice! WHY do it if its not required
> and really does nothing much. Warm feeling a suppose :-)
The Odyssey sounds like a good battery, no doubt about it.
But none of what I have posted has been an attempt to justify any particular brand
of battery. My whole point has been to show the differences between various
battery *types*, the differences in charge voltage, and the difference caused
by temperature.
> Yes, but for the Nth time you have failed to respond with ANY facts in
> regard to how much longer or how much better. Longer and better are not
> enough for ANY informed decision. If it makes a 8 year battery into a 10
> year one I could care less. If it makes a 3 year battery into a 1/2 year
> battery I am interested. I suspect its the former and demonstrability not
> the latter.
I do not have those figures and I am not equipped to do the long term research.
I do have anecdotal evidence (from several places) that improper charging causes
batteries to fail and I have the admonitions of the need for proper charge
voltage and temperature compensation from at least two battery manufacturers.
I have experienced the problem with sealed VRLA batteries in stationary, marine,
and aviation uses so I *KNOW* there is a problem using standard voltage
regulators. This anecdotal information is supported by documentation from battery
manufacturers who provide complete information. I point to the failure of
Concorde batteries in very short periods of time and I suspect they would have
lasted just fine if charged properly. I had to replace the four 2-year-old
AGMs on my boat when I got it because the batteries were totally destroyed.
Two would not hold a charge nor would they draw any charge current. One had a
shorted cell but otherwise would hold a charge and o
perate at about 1/2 of rated capacity. The forth had all its cells functional
but had only about 1/2 capacity. Since I have replaced the batteries and built
a proper charge and distribution system there have been no more problems.
I just completed a capacity cycle with my now almost 2-years-old "new" batteries.
Capacity was about 96% of rated capacity when discharged to the manufacturer's
specified endpoint of 1.75V per cell or 10.5V for a 12V battery at very close
to the 20 hour rate. Granted this is only a single data point and not statistically
valid but it does suggest that there is an issue. Abused the batteries
died a quick death (and I would suggest that those batteries had failed
LONG before I got them) and properly cared for they are showing almost-new characteristics.
Here is another data point. Battery manufacturers have a vested interest in reducing
warranty returns. Charging abuse causes early returns. This implies to
me that proper treatment allows them to greatly reduce in-warranty returns.
Given that battery warranties are not 8 years long this suggests that it will
have an effect within a relatively short period of time.
Clearly you are going to argue until the cows come home. Feel free. I have presented
information I consider to be significant. Hopefully people will make
up their own minds about this.
>>Perhaps. OTOH, it is the main battery that gets all the use.
>
>
> Yes and if the backup battery has "lost its will to live" and lets you down
> when you need it, what then.
Before putting the older battery back into use I would certainly expect that someone
would have done a capacity test. That certainly implies that it is likely
to perform reasonably well.
One can also consider the "bathtub" reliability curve. The older battery will
have passed the point of infant mortality and is very possibly the more reliable
of the two batteries. But I can't prove it without long-term, large-sample
failure tests.
> A backup is worse than useless if its not
> reliable. MY position is if its not good enough for prime time its not
> anything I want as backup. This is a general comment but in my case the
> backup is really in use all the time as I have a electrically dependent
> engine and both systems must be on and ready for instant prime time. Some
> what different than mag powered VFR day flying.
Well, best of luck with your system. I think you should do what makes you most
comfortable.
I must admit, I am getting tired of this exchange as we keep saying the same things.
I stand by my statements and suggest that the people on the list do their
own research in order to satisfy themselves that their chosen design meets
their comfort level for reliability.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Automotive Landing Lights? |
>
>My panel space is limited and I wish to eliminate installing a switch
>for the taxi light. I plan to wire up the low beam element with the high
>beam element (in parallel) together.
This will double the power dissipation for each lamp
assembly. It's doubtful that the lamp designer intended
for this product to be operated with both filaments lit.
Life could be spectacularly short.
>I want to install one switch, off
>in down position, wig wag in middle position, and lights on in up
>position.
>
>The manufacture states the high beam element is 55 watts and the low
>beam element is 45 watts. This is 100 watts collectively. Ohms law says
>that 100 watts divided by 14 volts is about 7 amps of current flow.
>Since I want to install two lamps, this will give a total current flow
>of 14 amps. I see no problem with this. In my car, the elements seem to
>go for years. My concern was running both elements simultaneously would
>reduce the life to a few hours. I guess I will have to attach one to my
>battery and battery charger and let it glow for a few days to conduct a
>test.
good idea . . .
>Of the five different lights I bought (and returned), I found that just
>because two lamps are round it does not mean their lighting pattern will
>be the same. Minor differences in the reflector shape plays a major role
>in light pattern. I found these to work very well, especially when you
>replace the 55 watt bulb with a 100 watt bulb.
>http://www.autoanything.com/products/product_sp.aspx?p_id=1333&se=hella_
>light_optilux_2500_angel_eye_kit
>
>Also check out http://www.piaa.com/Bulbs/Bulbs-H4.html
>
>So, is there anyone out there that has ganged the elements together?
Why the quest for so much power? I have Kitfox builders that installed
a 25w halogen flood in each wing tip . . . pointed mostly down but slightly
forward and outboard. The visual clues that REALLY help you put the
wheels on the ground gracefully are what's visible under the wings.
Dual filament lamps are attractive to me mostly because they offer
a "spare" lamp in each assembly . . . a back up to the main lamp. While
low beam filaments don't put the light into the same places as high
beam, they're better light than no light if you have only one, high
power, external light and plan to fly a lot.
I wouldn't discourage you from pursuing your operational goals
but given the logarithmic response characteristics of the human
eye and other variabilities in the system, doubling the power expended
in the effort does not translate into twice the visibility, safety,
utility, reliability etc. In fact, doubling the power probably
translates to reduced reliability simply because parts are stressed
harder and you've not taken advantage of the dual filament bulbs as
having built-in backups.
I once took a customer for a ride one evening in my J-3 using a
fisherman's hand-held, 6v lantern as the sole source of lighting
for the excursion. 6V a 0.5A was 3 WATTS of total energy expended.
The device was quite adequate for the intended task.
Bob . . .
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Cont VS Bendix injection systems |
Paul Messinger wrote:
>
> I can hardly ask others to be specific when I am not; so here are the
> details on the two specific injection systems and why one is so much better
> in hot starting.
Yes, the Continental system is easier to start when hot. No question about it.
And I am aware of the differences in the design.
Hot starting is a very small part of the operating envelope of the injection system
and I certainly do not choose to select my injection system purely on the
basis of its hot-starting characteristics.
> This from a 1971 version of the A&P Powerplant Handbook.
>
> I recognize that not all, in fact most (many?) Cont engines used the Bendix
> system.
I didn't know that any of the Continental engines used the Bendix RSA fuel injection
system.
> My S35 used the Cont system :-)
> My MK21 Exec had the Bendix system :-(
It was powered by a Lycoming engine.
> Hot start problems made the Bendix system unacceptable to me.
>
> I sometimes wonder why so many just assume its part of the beast and do not
> rise up and insist it be fixed.
>
> Having experenced both I cannot understand how its put up with.
That is fine. It takes many horses to make up a horse race. I happen to like
the fact that the Bendix fuel servo measures mass airflow and adjusts fuel flow
accordingly. This keeps mixture relatively constant during climb and descent.
The servo also compensates for variations in fuel pressure thus accommodating
normal variation between fuel pumps without requiring adjustment.
Continental's injection system is simpler. There is a lot to be said for simple.
The fuel return line is required because the fuel pump is a positive displacement
pump. The volume of output is purely a function of RPM, not fuel requirement.
A bypass valve is required to set the fuel pressure. Then you have
the issue of where to plumb the fuel return line. Either you make the fuel selector
much more complex in order to plumb the return line to the tank from which
fuel is being drawn (lots of extra complexity) or you have the return line
go to one specific tank and accept that you must burn from that tank first before
burning fuel from any other tank lest you start pumping fuel overboard.
Of course you can opt for the header tank approach but then you have to get fuel
to the header tank.
But most of this is a moot point. If you opt for a Continental engine you are
going to get what comes with the engine. Likewise with Lycoming.
As for the Lycoming hot-starting problem, I have seen a simple hack that solves
the problem for the Bendix RSA injection system. I saw a homebuilt where the
builder installed an extra line and a two-way valve between the fuel servo and
the flow divider and plumbed the line back to one of the tanks. During a hot
start he just needed to open the valve to divert the fuel to the return line,
turn on the boost pump, and open the mixture control. Fuel would then flow
through the fuel pump, the fuel servo, and the line to the flow divider. This
would purge the vapor and cool all the components. Now his hot starts were
a breeze. Isn't it nice to be able to deal with this things in OBAM aircraft?
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Cont VS Bendix injection systems |
Paul Messinger wrote:
>
> I can hardly ask others to be specific when I am not; so here are the
> details on the two specific injection systems and why one is so much better
> in hot starting.
Yes, the Continental system is easier to start when hot. No question about it.
And I am aware of the differences in the design.
Hot starting is a very small part of the operating envelope of the injection system
and I certainly do not choose to select my injection system purely on the
basis of its hot-starting characteristics.
> This from a 1971 version of the A&P Powerplant Handbook.
>
> I recognize that not all, in fact most (many?) Cont engines used the Bendix
> system.
I didn't know that any of the Continental engines used the Bendix RSA fuel injection
system.
> My S35 used the Cont system :-)
> My MK21 Exec had the Bendix system :-(
It was powered by a Lycoming engine.
> Hot start problems made the Bendix system unacceptable to me.
>
> I sometimes wonder why so many just assume its part of the beast and do not
> rise up and insist it be fixed.
>
> Having experenced both I cannot understand how its put up with.
That is fine. It takes many horses to make up a horse race. I happen to like
the fact that the Bendix fuel servo measures mass airflow and adjusts fuel flow
accordingly. This keeps mixture relatively constant during climb and descent.
The servo also compensates for variations in fuel pressure thus accommodating
normal variation between fuel pumps without requiring adjustment.
Continental's injection system is simpler. There is a lot to be said for simple.
The fuel return line is required because the fuel pump is a positive displacement
pump. The volume of output is purely a function of RPM, not fuel requirement.
A bypass valve is required to set the fuel pressure. Then you have
the issue of where to plumb the fuel return line. Either you make the fuel selector
much more complex in order to plumb the return line to the tank from which
fuel is being drawn (lots of extra complexity) or you have the return line
go to one specific tank and accept that you must burn from that tank first before
burning fuel from any other tank lest you start pumping fuel overboard.
Of course you can opt for the header tank approach but then you have to get fuel
to the header tank.
But most of this is a moot point. If you opt for a Continental engine you are
going to get what comes with the engine. Likewise with Lycoming.
As for the Lycoming hot-starting problem, I have seen a simple hack that solves
the problem for the Bendix RSA injection system. I saw a homebuilt where the
builder installed an extra line and a two-way valve between the fuel servo and
the flow divider and plumbed the line back to one of the tanks. During a hot
start he just needed to open the valve to divert the fuel to the return line,
turn on the boost pump, and open the mixture control. Fuel would then flow
through the fuel pump, the fuel servo, and the line to the flow divider. This
would purge the vapor and cool all the components. Now his hot starts were
a breeze. OTOH this introduces another single-point-of-failure. Isn't it nice
to be able to deal with this things in OBAM aircraft?
And I happen to like Lycoming engines. The O-320/360/540 series (parallel valve)
engines usually make or pass TBO. They seem very reliable to me, enough so
that I was willing to do two ocean crossings behind one.
The Continental IO-520 and IO-550 engines seem to need a top overhaul halfway
through the TBO run. LOP operation may change this for the Continental engines
but I suspect we need to hear from the GAMI folks on this. OTOH, if it improves
the longevity of the Continental engines, what will it do for the Lycoming
engines that are already typically making it to TBO?
But all of this is supposition on my part. I have many thousands of hours flying
behind Lycoming engines and relatively few flying behind Continental engines
(almost all of it in the C-182 and early C-310s). I also have about 1000 hours
flying behind the Chinese Huosai 285 hp radial engine which beats them all
on reliability. :-) I just know what my experiences are. YMMV.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Battery data and etc |
Paul Messinger wrote:
>>Well, getting all pissy at each other doesn't really solve anything, does
>
> it. Drinking beer after a day of flying or playing with airplanes is far
> more pleasant.
>
> I Guess I cannot win no matter what I do.
>
> I was being complimentary to your nice reply.
So was I. I was agreeing that getting pissy in previous exchanges wasn't getting
us anywhere and that sitting down over a beer would be much more pleasant.
I apologize if I wasn't being clear.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Battery data and etc |
Paul Messinger wrote:
>>Well, getting all pissy at each other doesn't really solve anything, does
>
> it. Drinking beer after a day of flying or playing with airplanes is far
> more pleasant.
>
> I Guess I cannot win no matter what I do.
>
> I was being complimentary to your nice reply.
So was I. I was agreeing that getting pissy in previous exchanges wasn't getting
us anywhere and that sitting down over a beer would be much more pleasant.
I apologize if I wasn't being clear.
BTW, the beer offer still stands.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> batteries |
| Subject: | Re: engine hot starting and more on |
batteries
batteries
>
>
>----- Original Message -----
>From: "Brian Lloyd" <brianl(at)lloyd.com>
> > > I am not pushing Odyessy, but they only cost around double the Panasonic
>and
> > > still well under $100 delivered and have the ability to sit around with
>NO
> > > need for a float charger to keep it topped off like the Panasonic does.
I don't know of anyone who has found it necessary to keep
a float charger on a Panasonic battery to achieve satisfactory
service . . . and there are many hundreds of Panasonic batteries
flying in airplanes.
> > All batteries have some level of self discharge. The lead alloy can
>reduce that to some extent but you can't eliminate that. The warmer the
>battery, the faster the level of self discharge. Keeping a battery on a
>proper float charge is a safe thing to do. YMMV.
>
> Look at the self discharg times for the Panasonic vs the good ones. Sure
>its temp dependent but we are looking at nearly a order of magnitude lower
>self discharge rate; one that eleminates in most cases, any need for battery
>float chargers that the Panasonic types require.
>
>At 25C and 12 months the panasonic has LOST 36% of its charge. Odyssey
>states at 25C it can be stored for 2 YEARS before needinmg to be recharged.
>I do not remember the data on the Optima but its at least a year.
>
>I did a test on one of my Odyssey batterys and it needed 15 min at one amp
>after 9 months to tpo off using their recommended charger. The next day the
>battery indicated 100% charge per their resting V table using a 0.025%
>accurate meter.
>
>A Panasonic needed over 12 hours to fully charge with the same charger etc.
>
>Not needing to use a float charger is nice! WHY do it if its not required
>and really does nothing much. Warm feeling a suppose :-)
Why is this even a concern? The AVERAGE use of an SE lightplane
is 50 hrs/year or 4 hrs/month. Unless you're going to do ALL your
flying in two days out of every year, why are self-discharge
characteristics even a part of your value added considerations?
I just spent several tens of thousands of $ of RACs money looking
at batteries for what must be the umpteenth time batteries have
been studied at Beech/RAC over the past 50 years. I've walked through
the $high$ and $low$ battery factories and sifted their respective
marketing hypes. My anticipated presentation to RAC engineering,
customer service groups and purchasing is not going to be much
different than for the OBAM aircraft community.
Yes, there are some design features that produce striking
differences in details of performance between the various
products offered . . . but when considering product with
a 2:1 or greater price difference, how does the lowly consumer
make a considered judgement for return on investment?
IF your planned operating mode requires your battery to have
a minimum capacity to back up engine driven power sources,
then you are going to have to replace an otherwise perfectly
good battery long before it quits cranking the
engine. In this case, the difference in performance between
the $high$ and $low$ products does not seem to justify the cost. If
you add in the time it takes to do periodic capacity tests
so that you can wring the last few months of service out
of a $high$ battery, then you've driven the cost of ownership
for the already $high$ battery still higher because you've added
maintenance labor to the equation. This same situation
arose in the heavy iron airplanes on flooded ni-cads . . .
they were stellar performers when they worked but required
MUCH more hands-on support that drove their already-high
cost of ownership out the roof.
If you have multiple engine driven power sources and battery
capacity is not an issue, then you can run the battery until
it won't crank the engine any more. I don't have any hard
field data on this situation (our heavy iron driving brethren
are not allowed to explore this operating scenario). However,
it's still not clear to me that one can expect to get 2 times
the SERVICE LIFE from a 2x dollars battery.
Don't get me wrong . . . the Enersys (Hawker) line of batteries
are among the "best" if not the very best batteries you can
buy with respect to some characteristics. The REAL question
to be asked and answered is, "What is my investment in time
and dollars to use Enersys or any other product to achieve
the REAL LIFE operating qualities I need from my airplane?"
The answer goes far beyond the marketing hype that claims
"my self discharge rate is a fraction of their self discharge
rate". That may well be true but should I care?
For my time and dollars, I think an all-electric system on
a budget that gets a new el-cheepo RG battery installed
every fall represents about a 50 cents per flight hour
cost of ownership adder for achieving stellar system
reliability. That could be reduced further by running
the battery until it doesn't crank any more. But then
I'm at-risk for doing a battery replacement at some unhandy
time with a high probability of it being away from the
home field.
Given all other costs of owning and operating an airplane,
the yearly replacement of a low-cost battery seems to offer
the lowest cost of ownership while maintaining a very high
level of SYSTEM reliability. Under this scenario, concerns
for self-discharge characteristics and/or selecting the
right "float" charger are not even on the radar much less
a serious point of consideration.
The folks behind a booth at OSH would like to paint the
whole OBAM aircraft community with the same broad brush
loaded with the same color of paint. As informed
system designers, we have an opportunity to maximize
the efficiency of our efforts in ways that don't necessarily
match their rational for considering their product over
anyone else's.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: wiring security |
>
>
>
>Hi guys,
>
>On advice, I began the task of progressively redoing tie-ties that have
>put both singular or grouped wires directly against metal. This typically
>required cutting one and replacing it with 3 tie-ties to make two grips
>and a standoff. It looked good, but seems to offer more motion to the
>wires thru engine vibration acting against the wires. One has to consider
>which is worse, "movement and fatigue" or "wear by tie-tie clamping wires
>against a surface and cutting insulation". I've not seen much discussion
>of this on the Matronics pages.
>
>
>If there are opinions or "rules" on these considerations beyond the usual
>Adel clamps, etc
>
>I'd be interested to hear about this area where wires traverse the smooth
>boundarys of the motor mount and firewall.
Potential for damage due to rubbing is several orders of
magnitude higher than damage due to flexing. The fine stranding
we insist on for high vibration environments all but completly
negates flexing issues . . . but you can do a rub-through in
a few tens of hours of operation. If the plastic tye-wrap was
considered suited to the particular task, then plastic band-clamps
might be more attractive.
Bob . . .
________________________________________________________________________________
| From: | Jerry2DT(at)aol.com |
| Subject: | Heat tolerance of batteries |
List,
I have the option of installing my Odyssey PC680 in the cabin next to the
firewall in my RV6a, or under the cowling on the firewall like the RV7a. I'm
wondering about how the heat would affect it with those oven-like temps. Thanks
for any and all ideas.
Jerry Cochran
________________________________________________________________________________
| From: | "Ralph E. Capen" <recapen(at)earthlink.net> |
| Subject: | Re: Heat tolerance of batteries |
I put mine just aft of the firewall using the Vans battery box - it fits nicely
in between the stiffeners right under the cutout for the oil filter stuff.
Photo's - zap me directly.....
-----Original Message-----
From: Jerry2DT(at)aol.com
Subject: AeroElectric-List: Heat tolerance of batteries
List,
I have the option of installing my Odyssey PC680 in the cabin next to the
firewall in my RV6a, or under the cowling on the firewall like the RV7a. I'm
wondering about how the heat would affect it with those oven-like temps. Thanks
for any and all ideas.
Jerry Cochran
________________________________________________________________________________
| Subject: | Automotive Landing Lights? |
The lens tells you almost nothing about the beam pattern. What you need is
a reflector that is an accurate parabolic shape in order to deliver a narrow
(i. e., focused) beam of light. The lens merely scatters (more or less,
depending on its design) the light bounced off the reflector surface. The
reflectors in such systems as the very bright lights (see:
http://www.spectrolab.com/DataSheets/SX16/ILS_SX-16.pdf) used on police
helicopters, for example, are relatively deep electroformed nickel parabolic
shapes with coatings to enhance the reflectivity, and these can deliver
(with a xenon short arc lamp) a beam spread of less than 5 degrees.
Automotive headlamps are never going to match that kind of performance, but
as Bob has said, 3 watts from a cheap lantern can do the job.
Best regards,
Rob Housman
Europa XS Tri-Gear A070
Airframe complete
Irvine, CA
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
Benford2(at)aol.com
Subject: Re: AeroElectric-List: Automotive Landing Lights?
In a message dated 6/21/2004 4:02:42 PM Mountain Daylight Time,
gbordelon(at)hess.com writes:
>
> I want to add more landing/taxi lighting to my aircraft. I went down to
> Pep Boys and purchased several auto headlights, driving lights, and fog
> lights. I conducted some experiments at night and found there is huge
> difference in illumination pattern among the lights I purchased. I also
> found that using a combination high & low beam head light worked very
> well when BOTH elements were turned on. Anyone on the list have any
> experience using high/low beam simultaneously? I'm a bit concerned that
> having both elements glowing will significantly shorten the life of the
> bulb to only a few hours. Any experiences out there? Thx
Naw. The bulb will last a long time but you will be pulling some serious
amps
to run them both at the same time. You want to use spot bulbs for the
landing
light and fog/driving lights for taxi lights. All ya got to do is look at
the
lens, that determines the light pattern.
Ben Haas N801BH.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Heat tolerance of batteries |
>
>List,
>
>I have the option of installing my Odyssey PC680 in the cabin next to the
>firewall in my RV6a, or under the cowling on the firewall like the RV7a. I'm
>wondering about how the heat would affect it with those oven-like temps.
>Thanks
>for any and all ideas.
Batteries are thermally massive and do not respond quickly
to transient ambient temperature excursions. While there
are intervals of extra-ordinary ambient temps that occur under a
cowl, they're not terribly significant to care and feeding
of your battery. Primary mode of heat energy transfer from
engine to ambient in flight is radiated . . . I've seen
plastic parts melt due to radiated heat from stacks while
the ambient air temps around the parts was relatively benign.
Short durations of temperature spiking during after-shutdown
temperature rise do not significantly affect a battery.
Batteries have lived quite happily on both sides of the
firewall on many aircraft for decades. Pick a best location based
on performance (weight and balance) or maintenance convenience.
Bob . . .
________________________________________________________________________________
| From: | "Jeff Hildebrand" <jhildebrand(at)crownequip.com> |
| Subject: | Noise problems with JPI EDM-900 and autopilot |
We are having noise problems with our Lancair ES.
When we have the JPI EDM-900 engine analyzer and the STEC 55x autopilot
on at the same time, we get a static noise in our headsets. When I turn
off either one, the noise will go away.
It seems to be coming from the EDM-900, because when I have the
autopilot on already and I start the EDM it gives a little bit of static
on the startup sequence, then it is consistent after this.
When I have the EDM on already, and I turn on the autopilot, the static
is there immediately.
This noise is there when the engine is on or off.
Where do I go from here? How do I diagnose the problem and fix it?
Thanks,
Jeff Hildebrand
Lancair ES C-GSPH
www.lancaires.com <http://www.lancaires.com/>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | OV Module going bad? |
>Comments/Questions: Good morning, Bob. About 4 years ago, I installed
>your overvoltage protection package in a Kitfox with a two-stroke Rotax
>engine. As you probably know, Rotax uses a permanent magnet
>alternator. The setup I got from you includes the module and a relay.
>On my last flight (yesterday) indications of no charge kept popping up
>(voltmeter reading 12 and ammeter reading negative) but by turning the
>master off and on I was able to get the system charging again. This
>happened five or six times in the course of 1 1/2 hours. The time between
>failures was getting shorter and shorter.
Are you certain that the ov protection system is not properly doing its
job?
What are the voltage readings just before the system shuts off?
>I suspect that the relay is going. If you agree, I'd like to buy another
>one asap. If not, I'd be very interested in what you think the problem
>might be and what you suggest for diagnosing it.
Connect a multimeter into the system and make certain that
your voltage regulator is not mis-behaving. How old is
your battery? If it's getting soggy, the voltage regulator
may be mis-behaving due to loss of battery performance.
The system is very simple and there are few failures of
the OV protection system that would produce the symptoms
you cite. It seems probable that it's reacting to a real
OV condition that requires adjustment/replacement of a
regulator.
If push comes to shove, your existing OV module is
repairable . . . drop it to me in the mail and I'll take
a look at it.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
| Subject: | Z-14 Dual Alternators - Shunts & ANL's |
| From: | John Schroeder <jschroeder(at)perigee.net> |
Bob -
We have a 70 amp alternator and will put a B&C SD-20 on the vacuum pad for
the second system of the Z-14. The questions are shunts and ANL current
limiters.
1. Since B&C does not carry a 70 amp shunt, we ordered a 75 amp. Is this
OK?
2. Since B&C does not have a 20 or a 70 amp ANL, we ordered a 40 to use
on the 20 amp alternator and a 60 to use for the 70 amp alternator. Are
these OK?
3. Or should we try to obtain them elsewhere?
4. Are there any operational cautions to bear in mind using these
mismatches in components for the alternators?
Many thanks,
John
________________________________________________________________________________
| From: | "Trampas" <tstern(at)nc.rr.com> |
| Subject: | Noise problems with JPI EDM-900 and autopilot |
Well the noise is either coming from power bus or from some sort of radiated
noise.
To see if radiated power intercom from separate power supply, like an
automotive "jump box". If noise is still there it is a radiated noise from
RF or magnetic fields. This is most likely not the problem.
The more likely problem is that the units are generating noise on power bus.
To check this take one of the units and power it from the "jump box" while
keeping the unit grounds connected. If noise goes away, you most likely have
a unit which generates noise on power bus. Sometimes electronic devices have
power supplies which produce noise spikes on power bus. If the device is
doing this often placing a diode inline with the device will remove the
noise. Other times the device draws large amounts of power for brief periods
which generates noise on power bus. In these cases placing an
inductor/capacitor filter as Bob has outlined fixes the problem.
Either way I would personally recommend an inductor/cap filter on the
intercom power as that power supply noise is really common.
Regards,
Trampas
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jeff
Hildebrand
Subject: AeroElectric-List: Noise problems with JPI EDM-900 and autopilot
We are having noise problems with our Lancair ES.
When we have the JPI EDM-900 engine analyzer and the STEC 55x autopilot
on at the same time, we get a static noise in our headsets. When I turn
off either one, the noise will go away.
It seems to be coming from the EDM-900, because when I have the
autopilot on already and I start the EDM it gives a little bit of static
on the startup sequence, then it is consistent after this.
When I have the EDM on already, and I turn on the autopilot, the static
is there immediately.
This noise is there when the engine is on or off.
Where do I go from here? How do I diagnose the problem and fix it?
Thanks,
Jeff Hildebrand
Lancair ES C-GSPH
www.lancaires.com <http://www.lancaires.com/>
________________________________________________________________________________
| From: | erie <erie(at)shelbyvilledesign.com> |
| Subject: | Re: wiring security |
Am I the only one that seems perturbed at the manufacturers use of wire
ties??? with the average
certified plane's age reaching 30+ years, the damn things get brittle
and fall off (usually first requiring a minor blood sacrifice...)
. On every plane my partner and I rebuild, I spend anywhere from 10-30
hours retieing the harness, at least then I know the
next person to work on it won't have scarred up hands from the cut ends
of the wire ties, though I've had a lot of people comment
that they haven't seen a tied harness in years and wish more people
would do it.
erie
Robert L. Nuckolls, III wrote:
>
>
>
>>
>>
>>
>>Hi guys,
>>
>>On advice, I began the task of progressively redoing tie-ties that have
>>put both singular or grouped wires directly against metal. This typically
>>required cutting one and replacing it with 3 tie-ties to make two grips
>>and a standoff. It looked good, but seems to offer more motion to the
>>wires thru engine vibration acting against the wires. One has to consider
>>which is worse, "movement and fatigue" or "wear by tie-tie clamping wires
>>against a surface and cutting insulation". I've not seen much discussion
>>of this on the Matronics pages.
>>
>>
>>If there are opinions or "rules" on these considerations beyond the usual
>>Adel clamps, etc
>>
>>I'd be interested to hear about this area where wires traverse the smooth
>>boundarys of the motor mount and firewall.
>>
>>
>
> Potential for damage due to rubbing is several orders of
> magnitude higher than damage due to flexing. The fine stranding
> we insist on for high vibration environments all but completly
> negates flexing issues . . . but you can do a rub-through in
> a few tens of hours of operation. If the plastic tye-wrap was
> considered suited to the particular task, then plastic band-clamps
> might be more attractive.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | Charlie <charleyb(at)earthlink.net> |
| Subject: | Low voltage on Main Bus |
Bob, et.al.,
I'm not sure I even have a problem. But I don't have a clue as to how to
justify my situation, trouble shoot it, or solve it. I haven't run the
engine yet so can't guess what the alternator on line will produce. But...
My PC 680 battery is newly charged and reads 13.27 volts at the battery
terminals. My external power supply produces 13.65 volts measured at the
leads where they connect to my alternator lead and the airframe (ground.)
My panel installed voltmeter (VM-1000) reads voltage from the essential
bus. Using battery power only and switched to Essential (Endurance) bus
only, the voltage reads 13.1 volts - pretty much as it should be - a .17
volt drop. With the battery contactor closed and using battery power
only, the VM-1000 voltage reads 12.4 volts - a drop of .87 volts.
Turning the power supply on brings the voltage up to 12.9 volts - a drop
of .75 volts. The ammeter shows only .1 amp being used from the power
supply while on the main bus - that seems a bit low even with only the
VM-1000, the fuel gage system and a few other low power systems powered up.
I've wired things up IAW Bob's Z-13 scheme (All Elec On A Budget.) The
system is installed in an RV-6 with 4 AWG battery leads less than 10
inches long.
Is my voltage drop on the main system something to be worried about? If
so, how does one go about trouble shooting it or solving the problem?
Can the diode between the main and essential busses be the cause of the
big drop?
Charlie
RV-6A N11CB
San Antonio
________________________________________________________________________________
| From: | "Ralph E. Capen" <recapen(at)earthlink.net> |
| Subject: | Re: Low voltage on Main Bus pts rule name |
My identical configuration and experience.
I have also purchased a Schottky (from perihelion...) and expect a smaller
drop - although everyone says with the engine running and the alternator
moving trons it won't matter. I wanna see for myself.
There was a major set of discussions over this topic very recently so check
the archives
Ralph
----- Original Message -----
From: "Charlie" <charleyb(at)earthlink.net>
description ---- ---------------------- ------------------------------------
-------
>
> Bob, et.al.,
>
> I'm not sure I even have a problem. But I don't have a clue as to how to
> justify my situation, trouble shoot it, or solve it. I haven't run the
> engine yet so can't guess what the alternator on line will produce. But...
>
> My PC 680 battery is newly charged and reads 13.27 volts at the battery
> terminals. My external power supply produces 13.65 volts measured at the
> leads where they connect to my alternator lead and the airframe (ground.)
>
> My panel installed voltmeter (VM-1000) reads voltage from the essential
> bus. Using battery power only and switched to Essential (Endurance) bus
> only, the voltage reads 13.1 volts - pretty much as it should be - a .17
> volt drop. With the battery contactor closed and using battery power
> only, the VM-1000 voltage reads 12.4 volts - a drop of .87 volts.
> Turning the power supply on brings the voltage up to 12.9 volts - a drop
> of .75 volts. The ammeter shows only .1 amp being used from the power
> supply while on the main bus - that seems a bit low even with only the
> VM-1000, the fuel gage system and a few other low power systems powered
up.
>
> I've wired things up IAW Bob's Z-13 scheme (All Elec On A Budget.) The
> system is installed in an RV-6 with 4 AWG battery leads less than 10
> inches long.
>
> Is my voltage drop on the main system something to be worried about? If
> so, how does one go about trouble shooting it or solving the problem?
> Can the diode between the main and essential busses be the cause of the
> big drop?
>
> Charlie
> RV-6A N11CB
> San Antonio
>
>
________________________________________________________________________________
| From: | Benford2(at)aol.com |
| Subject: | Re: Automotive Landing Lights? |
In a message dated 6/22/2004 9:30:14 AM Mountain Daylight Time,
RobH@hyperion-ef.com writes:
>
>
> The lens tells you almost nothing about the beam pattern. What you need is
> a reflector that is an accurate parabolic shape in order to deliver a narrow
> (i. e., focused) beam of light. The lens merely scatters (more or less,
> depending on its design) the light bounced off the reflector surface. The
> reflectors in such systems as the very bright lights (see
Bull Shit, you can have a perfect parabolic reflector and projecting it
through a very diffusing lens will scatter the light as the lens was designed.
You
answered your question in your first paragraph. So maybe you might want NOT
to say "The lens tells you nothing about the beam pattern"
________________________________________________________________________________
| From: | "Jerzy Krasinski" <krasinski(at)provalue.net> |
| Subject: | Re: Low voltage on Main Bus pts rule name |
Charlie,
Your essential bus is connected to the main bus through a diode, and the
voltage drop between the battery and the essential bus is exactly what is
supposed to be in the presence of the diode.
Jerzy
----- Original Message -----
From: "Charlie" <charleyb(at)earthlink.net>
description ---- ---------------------- ------------------------------------
-------
>
> Bob, et.al.,
>
> I'm not sure I even have a problem. But I don't have a clue as to how to
> justify my situation, trouble shoot it, or solve it. I haven't run the
> engine yet so can't guess what the alternator on line will produce. But...
>
> My PC 680 battery is newly charged and reads 13.27 volts at the battery
> terminals. My external power supply produces 13.65 volts measured at the
> leads where they connect to my alternator lead and the airframe (ground.)
>
> My panel installed voltmeter (VM-1000) reads voltage from the essential
> bus. Using battery power only and switched to Essential (Endurance) bus
> only, the voltage reads 13.1 volts - pretty much as it should be - a .17
> volt drop. With the battery contactor closed and using battery power
> only, the VM-1000 voltage reads 12.4 volts - a drop of .87 volts.
> Turning the power supply on brings the voltage up to 12.9 volts - a drop
> of .75 volts. The ammeter shows only .1 amp being used from the power
> supply while on the main bus - that seems a bit low even with only the
> VM-1000, the fuel gage system and a few other low power systems powered
up.
>
> I've wired things up IAW Bob's Z-13 scheme (All Elec On A Budget.) The
> system is installed in an RV-6 with 4 AWG battery leads less than 10
> inches long.
>
> Is my voltage drop on the main system something to be worried about? If
> so, how does one go about trouble shooting it or solving the problem?
> Can the diode between the main and essential busses be the cause of the
> big drop?
>
> Charlie
> RV-6A N11CB
> San Antonio
>
>
________________________________________________________________________________
| Subject: | Automotive Landing Lights? |
When you learn to read (I did say "almost nothing") and when you learn a few
things about lighting systems, and you can magically identify the function
of lens elements simply by glancing at the lens, and can identify the
mathematical curve of the reflector (again just by looking at it), then post
something knowledgeable on the subject. Meanwhile, don't accuse others of
propagating bull shit.
You are correct, however, that a diffusing lens will scatter the beam, which
is exactly the wrong thing to do when you are trying to focus a narrow beam
of light.
What I did not say in my original post was that not all of the light from
the lamp is focused by the reflector. I'll leave it as an exercise for the
student to determine where that light goes. Hint: it will help you see the
runway edges.
Best regards,
Rob Housman
Europa XS Tri-Gear A070
Airframe complete
Irvine, CA
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
Benford2(at)aol.com
Subject: Re: AeroElectric-List: Automotive Landing Lights?
In a message dated 6/22/2004 9:30:14 AM Mountain Daylight Time,
RobH@hyperion-ef.com writes:
>
>
> The lens tells you almost nothing about the beam pattern. What you need
is
> a reflector that is an accurate parabolic shape in order to deliver a
narrow
> (i. e., focused) beam of light. The lens merely scatters (more or less,
> depending on its design) the light bounced off the reflector surface. The
> reflectors in such systems as the very bright lights (see
Bull Shit, you can have a perfect parabolic reflector and projecting it
through a very diffusing lens will scatter the light as the lens was
designed. You
answered your question in your first paragraph. So maybe you might want NOT
to say "The lens tells you nothing about the beam pattern"
________________________________________________________________________________
| From: | Joemotis(at)aol.com |
| Subject: | Re: Automotive Landing Lights? |
I, for one, continue to appreciate all of the listers (mostly everyone) that
disseminate their difference of opinions without the use of vulgarities.
Thank You
Joe Motis
601XL
33 years in the trades
and not real religious
________________________________________________________________________________
| Subject: | ND Alternator repair |
| From: | "David Chalmers" <David(at)ChalmersFamily.com> |
I just removed my failed ND alternator part number 100211-1411. I assume the regulator
or diodes have failed. Where can I get replacement parts? Is this an easy
repair or should I take it to a pro? Any advice appreciated.
Dave Chalmers
Redmond, WA
________________________________________________________________________________
| From: | "Gary Casey" <glcasey(at)adelphia.net> |
| Subject: | Tying wires, not wire ties |
<>
Now that you mention it, I am starting to tie my wire harness, but I don't
know the accepted knot. I have been using a clove hitch followed by an
overhand knot and it looks okay. What is the proper one?
Gary Casey
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: Cont VS Bendix injection systems |
I will not get into a long reply other than to say that the specific Cont
system I remarked about has a Single speed pump. Its a different cont or
what ever system that have a dual speed pump.
There is NO difference in fuel flow to the engine with or without the aux
pump running (vs the engine driven pump when the engine is running).
Bottom line is the cont system I am talking about had far less hot fuel to
dump out of the engine lines before the starting can occur.
Its not just the hot fuel in the lines to the cyl that boil but even the
fuel in the pumps boil when it gets to the final very low pressure poing
near the cyl injection points
You are talking about different variations with dual speed pumps etc.
In any event the Cont system I had was simple to hot start and the bendix
system I had was very hard to hot start due to the inabilty to flush hot
fuel from the engine.
I will end this discussion with this post as its really off the subject
Paul
----- Original Message -----
From: "Gary Casey" <glcasey(at)adelphia.net>
Subject: AeroElectric-List: Re: Cont VS Bendix injection systems
>
> I feel the need to comment on some of Paul's observations regarding the
> Continental vs. "Bendix" fuel injection systems. There is no electrical
> content here, so pardon us:
>
> < an
> Aux pump with no change in performance. (no concern about HI or LOW pump
> setting or changes in mixture with aux on or off)
>
> The pump output pressure is independent of altitude or ambient air
> conditions.>>
>
> I believe the opposite is true - the fuel flow in the Bendix system is
> independent of inlet pressure until it is insufficient for full flow
(about
> 15 psi), while the flow in the Continental system is sensitive to inlet
> pressure and there have been accidents caused by the pilot incorrectly
> choosing between high and low boost pump settings. In fact, if the
mixture
> is observed to change when the boost pump is turned on it should be
> considered a defect. One important difference - the fuel flow rate in the
> Continental system is also independent of another thing - the air flow
into
> the engine. The fuel flow in the Bendix system is inherently proportional
> to air flow and independent of engine speed and inlet pressure. The
> Continental system (unless the altitude-compensated version is used) does
> not compensate for air density, while the fuel flow in the Bendix system
is
> proportional to the square root of inlet air density, essentially half
> correcting for altitude and inlet air temperature. And the idle fuel flow
> control is essentially the same in both systems, being a function of
> throttle position, not air flow.
>
> < fuel
> return to the tank requirement. The aux pump can flush and replace hot
fuel
> with cool fuel.
>
> Bendix system cannot flush the fuel past the firewall as there is no fuel
> return setup. In a hot start condition a significant amount of fuel must
be
> purged from the system and out the exhaust before the engine can run.
>
> In the Cont system the aux pump can purge all the fuel except the small
> amount in the line to and the lines from the flow divider. This is
estimated
> to be 80% or more of the total fuel in the engine compartment (there is
> really only a very small amount of fuel in the non purgable part of the
> system). Thus the Cont design greatly reduces the amount of hot fuel that
> must be disposed of in a hot start.>>
>
> True, except that the Continental system doesn't purge fuel all the way to
> the spider, but to the fuel control valve. The Bendix system relies on
> pressure being maintained between the pump and within the fuel control
servo
> to prevent boiling in that area. If the pressure bleeds off after
shutdown
> there is a problem in the fuel pump that should be corrected. And hot
fuel
> doesn't cause the problem - it is the fuel vapor that is the issue. In
both
> systems it can be assumed that all the fuel in the spider is boiled out,
and
> the residual fuel from the distributor back to the fuel control valve may
or
> may not be partially vapor.
>
> And I think Paul mistyped - all Continental engines have the Continental
> system except for those where the customer insisted on the Bendix system
(I
> think the Beech Duke is one of those). I don't know of a single case
where
> a Lycoming buyer selected the Continental system even though the Bendix
> system, now manufactured by Precision Airmotive, has no corporate ties to
> Lycoming. Yes, the venturi in the Bendix system does cause a manifold
> pressure drop, but I don't know of any data that shows the system is more
> prone to icing because of it.
>
> < choice
> fly with an engine, using the Bendix system or at least as described
above.
> "Paul Messinger">>
>
> While the hot starting issue may be an area where the Continental has an
> advantage, I don't think there have been any fatalities caused by hot
start
> problems. There have been fatalities caused by improper boost pump
> operation in aircraft equipped with the Continental system. That, and the
> fact that the Bendix system is at least partially compensated for air
> density, are the reasons I prefer the Bendix system.
>
> Gary Casey
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Tying wires, not wire ties |
>
><hours retieing the harness, at least then I know the
>next person to work on it won't have scarred up hands from the cut ends
>of the wire ties, though I've had a lot of people comment
>that they haven't seen a tied harness in years and wish more people
>would do it.>>
>
>Now that you mention it, I am starting to tie my wire harness, but I don't
>know the accepted knot. I have been using a clove hitch followed by an
>overhand knot and it looks okay. What is the proper one?
>
>Gary Casey
The proper one is whatever works for you. I've used the square-knot
over clove hitch but my favorite is illustrated at:
http://www.aeroelectric.com/articles/cable_lace/cable_lace.html
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: ND Alternator repair |
>
>
>
>I just removed my failed ND alternator part number 100211-1411. I assume
>the regulator or diodes have failed. Where can I get replacement parts? Is
>this an easy repair or should I take it to a pro? Any advice appreciated.
Achieving the best rework of an alternator assumes you
have the skills, tools and/or the inclination to acquire
them. Given that ND alternator failures are very rare, you
can't depend on your own project offering lots of opportunities
for learning. Further, the price of a new-rebuild from the
car parts stores is so reasonable, it's difficult to justify
a DIY repair for any reason other that academic satisfaction.
Return on investment of time is poor and risks are higher.
However, if working on it yourself is attractive to you,
check for repair parts at http://www.alternatorparts.com
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
| From: | erie <erie(at)shelbyvilledesign.com> |
| Subject: | Re: Tying wires, not wire ties |
wrap twice, clove then square knot per AC 43.13 fig. 11-17
In reality, a clove and overhand knot works...and most A&P's I know do that.
erie
Gary Casey wrote:
>
><hours retieing the harness, at least then I know the
>next person to work on it won't have scarred up hands from the cut ends
>of the wire ties, though I've had a lot of people comment
>that they haven't seen a tied harness in years and wish more people
>would do it.>>
>
>Now that you mention it, I am starting to tie my wire harness, but I don't
>know the accepted knot. I have been using a clove hitch followed by an
>overhand knot and it looks okay. What is the proper one?
>
>Gary Casey
>
>
>
>
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Cont VS Bendix injection systems |
Paul Messinger wrote:
> I will not get into a long reply
Neither will I. Light Plane Maintenance had an excellent series of articles on
the two prevalent injection systems within the last year as I recall. Very informative.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | "Eric Ruttan" <ericruttan(at)chartermi.net> |
| Subject: | Re: ND Alternator repair |
As a middle ground I might suggest finding a local rebuilder.
I find one interested in explaining what they do and how they do it, the
education part, and they actualy do it, the reliability part.
I paid extra so he would let me watch, and made a friend.
> >I just removed my failed ND alternator part number 100211-1411. I assume
> >the regulator or diodes have failed. Where can I get replacement parts?
Is
> >this an easy repair or should I take it to a pro? Any advice appreciated.
>
> Achieving the best rework of an alternator assumes you
> have the skills, tools and/or the inclination to acquire
> them. Given that ND alternator failures are very rare, you
> can't depend on your own project offering lots of opportunities
> for learning. Further, the price of a new-rebuild from the
> car parts stores is so reasonable, it's difficult to justify
> a DIY repair for any reason other that academic satisfaction.
> Return on investment of time is poor and risks are higher.
>
> However, if working on it yourself is attractive to you,
> check for repair parts at http://www.alternatorparts.com
>
> Bob . . .
>
>
> -----------------------------------------
> ( Experience and common sense cannot be )
> ( replaced with policy and procedures. )
> ( R. L. Nuckolls III )
> -----------------------------------------
>
>
________________________________________________________________________________
| Subject: | Re: Tying wires, not wire ties |
Gary Casey wrote:
>
> < hours retieing the harness, at least then I know the
> next person to work on it won't have scarred up hands from the cut ends
> of the wire ties, though I've had a lot of people comment
> that they haven't seen a tied harness in years and wish more people
> would do it.>>
>
> Now that you mention it, I am starting to tie my wire harness, but I don't
> know the accepted knot. I have been using a clove hitch followed by an
> overhand knot and it looks okay. What is the proper one?
AC 43.13-1B Chapter 11 Section 12 has pictures of the different
processes. It is available as a PDF document on line at:
http://www.faa.gov/certification/aircraft/av-info/dst/43-13/AC43.13-1BChg1only.pdf
Hope this helps.
Regards,
Dennis
--
Dennis Golden
Golden Consulting Services, Inc.
________________________________________________________________________________
| From: | Hal / Carol Kempthorne <kempthornes(at)earthlink.net> |
| Subject: | Re: Tying wires, not wire ties |
What is needed for bundling wires is a tool, shaped like a mechanical
pencil . It would be touched to the bundle and the string would squirt
out, wrap around the bundle and set up snug.
Who wants to invent something and get rich?
hal
________________________________________________________________________________
| From: | Chad Robinson <crj(at)lucubration.com> |
| Subject: | Re: Tying wires, not wire ties |
Hal / Carol Kempthorne wrote:
>
> What is needed for bundling wires is a tool, shaped like a mechanical
> pencil . It would be touched to the bundle and the string would squirt
> out, wrap around the bundle and set up snug.
>
> Who wants to invent something and get rich?
Is Silly String strong enough to hold them together?
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Tying wires, not wire ties |
>
>
>What is needed for bundling wires is a tool, shaped like a mechanical
>pencil . It would be touched to the bundle and the string would squirt
>out, wrap around the bundle and set up snug.
>
>Who wants to invent something and get rich?
One may purchase tie-wrap installation tools that
will properly tension and then trim the tie so that
there are no sharp edges exposed. This tool and tying
technique is the technology of choice in virtually
every airplane factory today. I know of no production
facility that routinely uses flat-lace in fabrication.
I've articulated a preference for flat-lace but if I
had to set up a factory to manufacture a product that
needed some form of wire ties, I certainly choose to
go with tie-wraps installed with the proper tools.
It's not that one is strikingly "better" than the
other but a personal choice of how one plies his/her
craftsmanship. If I were judging an airplane at an
airshow, I don't think I could justify favoring
flat-lace over tie-wraps by very much if at all.
I'd certainly ding the showplane builder that didn't
cut off wire-ties flush for human-friendly results.
However, if one chooses to take the time to number wires
and document those numbers in a lucid and well organized
wire book, I could happily offer credit for the effort.
This labor-intensive component of the craft has
significant value-added features that last for the life of
the airplane.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: OV Module going bad? |
>Bob,
>Here are answers to your questions and some comments from further trouble
>shooting.
>
>In 2000, when I did my panel, I wired the overvoltage hardware as you show
>in your Z3 drawing of 4/00 except I don't have the third "c" connection on
>the regulator to which you show a wire from the master switch.
What do you do with the "c" connection? My understanding is that
this connection needs to be tied to the bus. It's the voltage
sense input to the regulator.
> It has
>worked predictably for the past 70 flight ours. That is, when I tested it
>by pulling the alternator control breaker the voltmeter dropped to 12, the
>ammeter showed a discharge, and the warning light lit.
>
>What's happening now is during flight the voltmeter will drop from 13 - 13
>1/2 to 12 and the ammeter will show a discharge. (I am not seeing any
>indication of overvoltage. Plus the alternator control breaker does not
>trip.) That's when I cycle the master and the system resumes operation,
>i.e., voltage back up and ammeter shows that charging is taking place.
>
>At no time during the "failed" mode does the alternator warning light come
>on. Nor does it come on if I pull the alternator control breaker while in
>the "failed" mode. This doesn't make any sense to me. Does this give you
>any clue what may be the problem?
If your warning light is staying off and the circuit breaker is
not popping, then it appears that the relay is staying closed
and that the system is NOT being taken off line by either a real
or erroneously perceived OV condition.
>Yesterday this happened once during the run up. Then everything was fine
>for about 1/2 hour then I had five or more failures at all rpm settings in
>the next 15 or so minutes.
>
>The battery was "activated" in 2000 after sitting around for 7 years. It
>seems to work ok.
"Seems" is somewhat non-quantified. I'd run a battery load test on
it at a battery shop. Lessee . . . your engine probably cranks with
something on the order of 75-100 amps. So have the mechanic crank up
the test load to load the battery down to 9v and hold it there for
15 seconds. Your battery should put out no less than 100A at the
end of 15 seconds.
Batteries for larger engines will test to 250A or better in this
test. New 32 a.h. Panasonics test to over 500A with this test. A new
17 a.h. will test at over 300A.
>I, too, wonder about the rectifier/regulator (it's a unit made by Key West
>that's very popular in my aviation circles). But since this is an
>intermittent problem I'm not sure how I can reliably check it other than
>replace it (and I'm considering that, too).
>
>I have thought of bypassing the over voltage relay temporarily to see if the
>problem goes away. What do you think of that idea?
It's obvious that the problem is not producing an ov condition so there's
no risk in bypassing the ov protection system for the purpose of conducting
a troubleshooting experiment. Sounds like a good idea to me.
Bob . . .
________________________________________________________________________________
| From: | Mark Sherman <msherman95632(at)yahoo.com> |
| Subject: | Transponder connection |
Good morning all.
I am installing a Garmin GTX 320A transponder with a
Ameriking AK 350 encoder in my Zenith 701. There was
no installation manual with the unit so I downloaded
one from there web site. The encoder came with a
cable, with a plug on one end for the encoder and bare
wires on the other end for the transponder. I want to
ensure that I am reading the installation manual
correctly. They show a drawing of a 25 pin d-sub and
pin-out definitions. The widest part of the connector
is at the top with pin one at top row left and pin 25
at bottom row right. What it doesn't say is if this
is the back of the plug that I will be soldering to,
or the front of the plug that plugs into the
transponder. Which would reverse the pins. My best
guess is, it is the back that I will be soldering to.
Can anyone confirm this?
It is very expensive to have the smoke put back into
the box so I don't want to let any out.
Thanks
Mark S.
__________________________________
http://promotions.yahoo.com/new_mail
________________________________________________________________________________
| Subject: | Re Westach tach Sensor |
| From: | irampil(at)notes.cc.sunysb.edu |
06/23/2004 12:46:14 PM,
Serialize complete at 06/23/2004 12:46:14 PM
Thank you all for your comments!!!
I really appreciate it.
What little there is on the 720-4A is on page 32 of the Westach online
catalog
http://www.frostalarm.com/cat/p32.html
I completely agree that going in and measuring with a scope is the optimum
path
of enlightenment and I would if I could. My shop is in NY and the plane
is still
near FlightCrafters in Florida. So I was actually thinking about getting
one of
those handheld cheapy Velleman scopes or equivalent which would also help
diagnose
a balky Floscan 264. While I have plenty of electrical supplies in the
hangar (e.g.,
tefzel, crimpers, AMP connectors, etc.), There is no electronics
infrastructure
so I was hoping to put together a divider module up north before the next
trip
to the plane.
The NS chip seems like exactly what the doctor ordered what with a single
rail supply and cmos logic
out and autoadapting the threshold to the Vpp as the rotational speed
changes!
In going through the LM1815 pages on the web, I was led to
http://www.magsensors.com/
who seems to be the OEM for the Westach 720-4A and if you look
at their catalog pages of analog variable reluctance gear sensors, they do
have the
engineering specs I was looking for. They also have pre-built digital
sensors that
provide TTL output directly. (May the use the LM1815 too?!)
Gotta love choices!
Ira N224XS
10.5 of 40 hours test flight flown so far
________________________________________________________________________________
| From: | f1rocket(at)comcast.net |
| Subject: | Re: Transponder connection |
In the Garmin manuals that I have, the pin callout is a picture of the back of
the connector. Irrespective of that, the connector itself will have the pins
numbered on the front and the back. I would use that as my guide. This is all
very fresh in my mind as I just wired up my GTX327 transponder last night.
Randy
F1 Rocket
http://f1rocket.home.comcast.net/
>
> Good morning all.
>
> I am installing a Garmin GTX 320A transponder with a
> Ameriking AK 350 encoder in my Zenith 701. There was
> no installation manual with the unit so I downloaded
> one from there web site. The encoder came with a
> cable, with a plug on one end for the encoder and bare
> wires on the other end for the transponder. I want to
> ensure that I am reading the installation manual
> correctly. They show a drawing of a 25 pin d-sub and
> pin-out definitions. The widest part of the connector
> is at the top with pin one at top row left and pin 25
> at bottom row right. What it doesn't say is if this
> is the back of the plug that I will be soldering to,
> or the front of the plug that plugs into the
> transponder. Which would reverse the pins. My best
> guess is, it is the back that I will be soldering to.
> Can anyone confirm this?
>
> It is very expensive to have the smoke put back into
> the box so I don't want to let any out.
>
> Thanks
>
> Mark S.
>
>
>
> __________________________________
> http://promotions.yahoo.com/new_mail
>
>
>
>
>
>
________________________________________________________________________________
| From: | Mark Sherman <msherman95632(at)yahoo.com> |
| Subject: | Transponder connection |
About the transponder connection question I ask
earlier, It was miswritten, the terminals are crimped
not soldered. But the question remains.
Mark S.
__________________________________
http://promotions.yahoo.com/new_mail
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: ND Alternator repair |
My experience is in agreement with this. The old line 'auto-electric'
shops tend to have knowledgeable folks in the back that can not only fix
the problem, but have seen so many products that they have a good feel
for which models have high failure rates & which ones they rarely see,
even on very common models.
About 10 years ago, after the 3rd alternator failure (not ND) in about 5
hrs of flying, I took a pair of the dead units to the local
'hole-in-the-wall', greasy floored local shop. I walked in & said hello
to the owner/repair guy, who was repairing something & watching the
counter at the same time. I asked him if he could take a look when he
had time & tell me why they were failing. He glanced up at the
alternators from across the room, looked back down at his work & said
'bad armatures.'
When he disassembled & checked them, they both had open armature
windings. He'd seen that model so many times he knew what he would find.
Then he found me a rebuilt ND brand unit that had the same mounting
dimensions as the bad ones. His rebuild was still on the plane when I
sold it about 5 years later.
Charlie
Eric Ruttan wrote:
>
>As a middle ground I might suggest finding a local rebuilder.
>
>I find one interested in explaining what they do and how they do it, the
>education part, and they actualy do it, the reliability part.
>
>I paid extra so he would let me watch, and made a friend.
>
>
>
>>>I just removed my failed ND alternator part number 100211-1411. I assume
>>>the regulator or diodes have failed. Where can I get replacement parts?
>>>
>>>
>Is
>
>
>>>this an easy repair or should I take it to a pro? Any advice appreciated.
>>>
>>>
>> Achieving the best rework of an alternator assumes you
>> have the skills, tools and/or the inclination to acquire
>> them. Given that ND alternator failures are very rare, you
>> can't depend on your own project offering lots of opportunities
>> for learning. Further, the price of a new-rebuild from the
>> car parts stores is so reasonable, it's difficult to justify
>> a DIY repair for any reason other that academic satisfaction.
>> Return on investment of time is poor and risks are higher.
>>
>> However, if working on it yourself is attractive to you,
>> check for repair parts at http://www.alternatorparts.com
>>
>> Bob . . .
>>
>>
>> -----------------------------------------
>> ( Experience and common sense cannot be )
>> ( replaced with policy and procedures. )
>> ( R. L. Nuckolls III )
>> -----------------------------------------
>>
>>
>>
>>
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: ND Alternator repair |
You might want to check the slip rings on the armature for wear before
investing in a rebuild kit. Sometimes the slip rings are worn to the
point that it makes more sense to let a rebuilder have it than to just
replace the diodes, regulator, and brushes with a parts kit. A good
rebuilder will replace the slip rings. That will also confirm that you
can remove the bolts that hold the case together. Sometimes the bolts
are seized pretty tight but otherwise I have always found parts kits to
be easy to install. Sometimes you have to get creative and use a piece
of string or something to hold the brushes retracted for assembly.
Rebuilders use the part number you mentioned whereas the parts counter
usually wants to know what vehicle it came out of.
Ken
>>
>>
>>
>>I just removed my failed ND alternator part number 100211-1411. I assume
>>the regulator or diodes have failed. Where can I get replacement parts? Is
>>this an easy repair or should I take it to a pro? Any advice appreciated.
>>
>>
________________________________________________________________________________
| From: | Glenn Rainey <nimbusaviation(at)yahoo.com> |
My Long-EZ was built with a copper tube earth from
firewall to nose, curiously with a joint to a smaller
pipe diam at the station of the panel bulkhead.
Disliking that joint, I pulled the foward section, but
the main length of the pipe will have to stay, and
carry current. So.. will 4AWG suffice for the 3 ft or
so forward to the battery (with Hall sensor!), and
similarly 4AWG back from the firewall to the starter
(maybe 3 - 4 ft)? I will be turning an O-235-L2C with
one of those, umm.. 'light weight' starters. Maybe
some wt saving, and easier to work with 4AWG.
regards from Scotland,
Glenn Rainey
LEZ project (builder #2)
__________________________________
http://promotions.yahoo.com/new_mail
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | batteries//load dump testing etc |
----- Original Message -----
From: "Robert L. Nuckolls, III batteries" <bob.nuckolls(at)cox.net>
> > > > need for a float charger to keep it topped off like the Panasonic
does.
>
> I don't know of anyone who has found it necessary to keep
> a float charger on a Panasonic battery to achieve satisfactory
> service . . . and there are many hundreds of Panasonic batteries
> flying in airplanes.
>
>>
Bob; Perhaps you missed the background on my comment and the basis for the
"need for float charger"
I was responding to a statement that "ALL" batteries self discharge more or
less at the same rate.
I have data that shows that some have a TEN times lower self discharge rate
that others of the same general type. (AGM).
Panasonic will loose as much as 36% of its charge in 12 months while others
may loose only 5%.
Thus IF you store your aircraft for the 6 months you may need a float
charger with the Panasonic type battery. Other (expensive) brands can store
for 12 months with no noticable loss of capacity. But how many ownersreally
do (store for months on end) that anyway.
That said, Panasonic and the similar other brands often recommended on this
list are simply amazing in performance based on my testing. They can start
large auto engines and have Twice the CCA of the flooded cell certified
aircraft batteries. A real sleeper (in real performance) that YOU have been
recommending for years.
Only down side I can find is the somewhat weak terminal lugs and that is not
a problem in my opinion if the user also follows another of your great
recommendations and use the very flexable welding cable for the short
battery to aircraft leads.
Paul
________________________________________________________________________________
| From: | Ken <klehman(at)albedo.net> |
| Subject: | Re: Automotive Landing Lights? |
FWIW the plastic automotive projector lamps that I am using had a metal
strip inside the housing to cut off the top of the light beam. I removed
them with needle nose pliars and I believe the broader vertical beam
will be more suitable for aviation use. I used both driving and fog
lamps so it may have been only one or the other that had these metal
strips inside.
Ken
Rob Housman wrote:
>
>The lens tells you almost nothing about the beam pattern. What you need is
>a reflector that is an accurate parabolic shape in order to deliver a narrow
>(i. e., focused) beam of light. The lens merely scatters (more or less,
>depending on its design) the light bounced off the reflector surface. The
>reflectors in such systems as the very bright lights (see:
>http://www.spectrolab.com/DataSheets/SX16/ILS_SX-16.pdf) used on police
>helicopters, for example, are relatively deep electroformed nickel parabolic
>shapes with coatings to enhance the reflectivity, and these can deliver
>(with a xenon short arc lamp) a beam spread of less than 5 degrees.
>Automotive headlamps are never going to match that kind of performance, but
>as Bob has said, 3 watts from a cheap lantern can do the job.
>
>
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: engine hot starting and more on batteries |
I truly do not want any to reply to this as we have beat it to death.
Until someone has a real concrete set of info/test data; I will continue to
recommend that Bob's approach on batteries be followed.
Its been proven to be reliable, low cost, and safe. What more can one ask
in today's world?
Brian;
If you recall I never questioned that what you were quoting was not "better"
I only (from day one was asking for some backup data) as to how much better
and never seemed to get a reply. To me it is not argumentative to keep
asking for backup data that would define what "better" is or how much
"shorter" life was and under exactly what conditions that data applied to.
You have finally said you had no real test data (and neither do I) to refer
to that provided definitive info on exactly what was to be gained that an
engineer (vs. chemist) could look at and evaluate to see if it was cost or
safety effective in his/her aircraft.
I have been unable to get any definitive data as to what if any real benefit
a fancy expensive 3 charge charger will do for the average experimental
owner builder. Until such time as data is made available I can see no reason
to consider deviation from what Bob has suggested as it has been
demonstrated to be a good way to do as states above.
Paul
----- Original Message -----
From: "Brian Lloyd" <brianl(at)lloyd.com>
> Clearly you are going to argue until the cows come home. Feel free. I
have presented information I consider to be significant. Hopefully people
will make up their own minds about this.
>
________________________________________________________________________________
| From: | "Jeff Hildebrand" <jhildebrand(at)crownequip.com> |
| Subject: | Noise problems with JPI EDM-900 and autopilot |
After spending a few hours isolating our intercom and other components,
we found that it wasn't radiated noise from the power bus.
It turns out that it was radiated noise from the intercom wire that
connects the autopilot chime to the intercom. It turns out that the
volume was set too high on the STEC 55x autopilot. When it was set
correctly the noise disappeared.
For anyone out there with an STEC 55x autopilot, make sure that the
volume pot is set correctly.
Jeff Hildebrand
C-GSPH
www.lancaires.com
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Trampas
Subject: RE: AeroElectric-List: Noise problems with JPI EDM-900 and
autopilot
Well the noise is either coming from power bus or from some sort of
radiated
noise.
To see if radiated power intercom from separate power supply, like an
automotive "jump box". If noise is still there it is a radiated noise
from
RF or magnetic fields. This is most likely not the problem.
The more likely problem is that the units are generating noise on power
bus.
To check this take one of the units and power it from the "jump box"
while
keeping the unit grounds connected. If noise goes away, you most likely
have
a unit which generates noise on power bus. Sometimes electronic devices
have
power supplies which produce noise spikes on power bus. If the device is
doing this often placing a diode inline with the device will remove the
noise. Other times the device draws large amounts of power for brief
periods
which generates noise on power bus. In these cases placing an
inductor/capacitor filter as Bob has outlined fixes the problem.
Either way I would personally recommend an inductor/cap filter on the
intercom power as that power supply noise is really common.
Regards,
Trampas
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jeff
Hildebrand
Subject: AeroElectric-List: Noise problems with JPI EDM-900 and
autopilot
We are having noise problems with our Lancair ES.
When we have the JPI EDM-900 engine analyzer and the STEC 55x autopilot
on at the same time, we get a static noise in our headsets. When I turn
off either one, the noise will go away.
It seems to be coming from the EDM-900, because when I have the
autopilot on already and I start the EDM it gives a little bit of static
on the startup sequence, then it is consistent after this.
When I have the EDM on already, and I turn on the autopilot, the static
is there immediately.
This noise is there when the engine is on or off.
Where do I go from here? How do I diagnose the problem and fix it?
Thanks,
Jeff Hildebrand
Lancair ES C-GSPH
www.lancaires.com <http://www.lancaires.com/>
==
==
==
==
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Transponder connection |
>
>
>About the transponder connection question I ask
>earlier, It was miswritten, the terminals are crimped
>not soldered. But the question remains.
>
>Mark S.
Mark, for some reason I didn't see the original post come through.
Repeat your question please?
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
| Subject: | Re: Cont VS Bendix injection systems |
| From: | "George Braly" <gwbraly(at)gami.com> |
Paul,
The TCM starting issue has virtually nothing to do with "flushing hot
fuel from the system."
Rather, it has everything to do with the temperature of the internal
components of the mechanical fuel pump that come into contact with new
fuel from the tank.
If those components are hot enough to flash to vapor a significant
portion of the hydrocarbon components of the new incoming fuel stream -
- then there will be a "bloom" of vapor as the new fuel hits the inlet
portion of the mechanical fuel pump - - which will then nicely suffer a
classic vapor lock as the pump inlet "suction" is relieved by the bloom
of fuel vapor and the pump is no longer able to pull (suck) fuel uphill
to the inlet of the mechanical pump.
It is not helpful to an understanding of the problem to try to deal with
anything that happens downstream of that point - - as frankly, "HOT"
downstream of the mechanical pump is usually helpful to the final
result, not harmful.
If, during cranking or subsequent operation, a gram of fuel vaporizes
in one of the small stainless fuel lines, it is still a gram of fuel
that ends up going into the cylinder induction plumbing and eventually
into the cylinder and burning just like it would if it were liquid when
it entered or exited the fuel injector.
Regards, George
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Paul
Messinger
Subject: Re: AeroElectric-List: Re: Cont VS Bendix injection systems
I will not get into a long reply other than to say that the specific
Cont
system I remarked about has a Single speed pump. Its a different cont or
what ever system that have a dual speed pump.
There is NO difference in fuel flow to the engine with or without the
aux
pump running (vs the engine driven pump when the engine is running).
Bottom line is the cont system I am talking about had far less hot fuel
to
dump out of the engine lines before the starting can occur.
Its not just the hot fuel in the lines to the cyl that boil but even the
fuel in the pumps boil when it gets to the final very low pressure poing
near the cyl injection points
You are talking about different variations with dual speed pumps etc.
In any event the Cont system I had was simple to hot start and the
bendix
system I had was very hard to hot start due to the inabilty to flush hot
fuel from the engine.
I will end this discussion with this post as its really off the subject
Paul
----- Original Message -----
From: "Gary Casey" <glcasey(at)adelphia.net>
Subject: AeroElectric-List: Re: Cont VS Bendix injection systems
>
> I feel the need to comment on some of Paul's observations regarding
the
> Continental vs. "Bendix" fuel injection systems. There is no
electrical
> content here, so pardon us:
>
> < an
> Aux pump with no change in performance. (no concern about HI or LOW
pump
> setting or changes in mixture with aux on or off)
>
> The pump output pressure is independent of altitude or ambient air
> conditions.>>
>
> I believe the opposite is true - the fuel flow in the Bendix system is
> independent of inlet pressure until it is insufficient for full flow
(about
> 15 psi), while the flow in the Continental system is sensitive to
inlet
> pressure and there have been accidents caused by the pilot incorrectly
> choosing between high and low boost pump settings. In fact, if the
mixture
> is observed to change when the boost pump is turned on it should be
> considered a defect. One important difference - the fuel flow rate in
the
> Continental system is also independent of another thing - the air flow
into
> the engine. The fuel flow in the Bendix system is inherently
proportional
> to air flow and independent of engine speed and inlet pressure. The
> Continental system (unless the altitude-compensated version is used)
does
> not compensate for air density, while the fuel flow in the Bendix
system
is
> proportional to the square root of inlet air density, essentially half
> correcting for altitude and inlet air temperature. And the idle fuel
flow
> control is essentially the same in both systems, being a function of
> throttle position, not air flow.
>
> < fuel
> return to the tank requirement. The aux pump can flush and replace hot
fuel
> with cool fuel.
>
> Bendix system cannot flush the fuel past the firewall as there is no
fuel
> return setup. In a hot start condition a significant amount of fuel
must
be
> purged from the system and out the exhaust before the engine can run.
>
> In the Cont system the aux pump can purge all the fuel except the
small
> amount in the line to and the lines from the flow divider. This is
estimated
> to be 80% or more of the total fuel in the engine compartment (there
is
> really only a very small amount of fuel in the non purgable part of
the
> system). Thus the Cont design greatly reduces the amount of hot fuel
that
> must be disposed of in a hot start.>>
>
> True, except that the Continental system doesn't purge fuel all the
way to
> the spider, but to the fuel control valve. The Bendix system relies
on
> pressure being maintained between the pump and within the fuel control
servo
> to prevent boiling in that area. If the pressure bleeds off after
shutdown
> there is a problem in the fuel pump that should be corrected. And hot
fuel
> doesn't cause the problem - it is the fuel vapor that is the issue.
In
both
> systems it can be assumed that all the fuel in the spider is boiled
out,
and
> the residual fuel from the distributor back to the fuel control valve
may
or
> may not be partially vapor.
>
> And I think Paul mistyped - all Continental engines have the
Continental
> system except for those where the customer insisted on the Bendix
system
(I
> think the Beech Duke is one of those). I don't know of a single case
where
> a Lycoming buyer selected the Continental system even though the
Bendix
> system, now manufactured by Precision Airmotive, has no corporate ties
to
> Lycoming. Yes, the venturi in the Bendix system does cause a manifold
> pressure drop, but I don't know of any data that shows the system is
more
> prone to icing because of it.
>
> < choice
> fly with an engine, using the Bendix system or at least as described
above.
> "Paul Messinger">>
>
> While the hot starting issue may be an area where the Continental has
an
> advantage, I don't think there have been any fatalities caused by hot
start
> problems. There have been fatalities caused by improper boost pump
> operation in aircraft equipped with the Continental system. That, and
the
> fact that the Bendix system is at least partially compensated for air
> density, are the reasons I prefer the Bendix system.
>
> Gary Casey
>
>
==
==
==
==
________________________________________________________________________________
| From: | Mark Sherman <msherman95632(at)yahoo.com> |
| Subject: | Transponder connection |
Good afternoon Bob.
I am installing a Garmin GTX 320A transponder with a
Ameriking AK 350 encoder in my Zenith 701. There was
no installation manual with the unit so I downloaded
one from there web site. The encoder came with a
cable, with a plug on one end for the encoder and bare
wires on the other end for the transponder. I want to
ensure that I am reading the installation manual
correctly. They show a drawing of a 25 pin d-sub and
pin-out definitions. The widest part of the connector
is at the top with pin one at top row left and pin 25
at bottom row right. What it doesn't say is if this
is the back of the plug that I will be soldering to,
or the front of the plug that plugs into the
transponder. Which would reverse the pins. My best
guess is, it is the back that I will be soldering to.
Can anyone confirm this?
It is very expensive to have the smoke put back into
the box so I don't want to let any out.
Thanks
Mark S.
__________________________________
http://promotions.yahoo.com/new_mail
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: Cont VS Bendix injection systems |
I think you missed my point.
I agree with much of your comment.
However; My point is that the secret is cooling the mechanical pump with
cold fuel from the cold electric pump. Something not possible with the
Bendix system. Fuel from the electric pump is pressurized above vapor
pressure and does not vaporize at the hot engine pump. Further the cool fuel
is pushed past the pump into the mixture assy where it is also cooled and
exchanged even with the mix control in idle cutoff. Even if there is some
initial vapor produced it is purged back into the tank and is not a factor.
I assume one runs the electric pump long enough to cool things down a
little. Worked for me at 6,000ft in 110F heat soaked aircraft many times
when other acft ran the batterys down trying to start.
Once properly cooled enough and considering that need not be much, with the
pressure supplied by the electric pump it eliminates vapor lock during the
critical start. There is always electric pump pressure at the inlet and
thruout the mech pump and mix assy from the electric pump during its
operation and thus no possible suction to allow vapor lock at the inlet of
the pump.
I hope you review the Cont system (in the 1971 book) was referring to and
not some later system.
The key to my point is circulation of fuel works and it worked for me too
many times to count and the Bendix system design did not permit this and
was, in most pilots (I have talked to) experience hard to 'hot' start.
If you have an alternative why there is such a dramatic difference in the
Bendix system VS the Cont system as used in the S35 ( I am specifically
talking about that system and not other versions) I would be interested. I
found hot starts to be a non event! I have never been able to hot start the
Bendix system with out lots of cranking as one often makes a hot start into
a severely flooded engine start. I have never met a pilot that did not have
problems with the Bendix system and most failed to accept that in the S35 it
could be a non event.
To me as an engineer and mechanic the key is the ability to replace most of
the hot fuel and also cool most of the fuel system prior to any attempt to
crank the engine.
Paul
----- Original Message -----
From: "George Braly" <gwbraly(at)gami.com>
Subject: RE: AeroElectric-List: Re: Cont VS Bendix injection systems
>
>
> Paul,
>
> The TCM starting issue has virtually nothing to do with "flushing hot
> fuel from the system."
>
> Rather, it has everything to do with the temperature of the internal
> components of the mechanical fuel pump that come into contact with new
> fuel from the tank.
>
> If those components are hot enough to flash to vapor a significant
> portion of the hydrocarbon components of the new incoming fuel stream -
> - then there will be a "bloom" of vapor as the new fuel hits the inlet
> portion of the mechanical fuel pump - - which will then nicely suffer a
> classic vapor lock as the pump inlet "suction" is relieved by the bloom
> of fuel vapor and the pump is no longer able to pull (suck) fuel uphill
> to the inlet of the mechanical pump.
>
> It is not helpful to an understanding of the problem to try to deal with
> anything that happens downstream of that point - - as frankly, "HOT"
> downstream of the mechanical pump is usually helpful to the final
> result, not harmful.
>
> If, during cranking or subsequent operation, a gram of fuel vaporizes
> in one of the small stainless fuel lines, it is still a gram of fuel
> that ends up going into the cylinder induction plumbing and eventually
> into the cylinder and burning just like it would if it were liquid when
> it entered or exited the fuel injector.
>
> Regards, George
>
________________________________________________________________________________
| Subject: | Re: Cont VS Bendix injection systems |
| From: | "George Braly" <gwbraly(at)gami.com> |
TCM has a basic system that requires an electric boost pump.
Cessna , Beech and others, at different times have provided either
single speed boost pumps or two speed boost pumps, depending pretty much
on which side of the bed some engineer and the FAA got up on the day the
decision was made.
The two speed pumps are very nice to have and very useful.
I have seen a vapor lock so bad on a normally aspirated IO-550 that took
off from Bullhead City, Az - - with 100+F new fuel (above ground tanks)
loaded into the airplane - - that it vapor locked about 120 seconds
after takeoff.
HARD vapor lock.
LOW boost did not even touch the problem.
It took FULL RICH and HIGH boost to get the engine running again before
we hit the terrain.
One then current space shuttle mission specialist on board (PIC), me,
and two teenagers.
It made for some interesting Crew Resource Management.
Regards, George
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Paul
Messinger
Subject: Re: AeroElectric-List: Re: Cont VS Bendix injection systems
I think you missed my point.
I agree with much of your comment.
However; My point is that the secret is cooling the mechanical pump with
cold fuel from the cold electric pump. Something not possible with the
Bendix system. Fuel from the electric pump is pressurized above vapor
pressure and does not vaporize at the hot engine pump. Further the cool
fuel
is pushed past the pump into the mixture assy where it is also cooled
and
exchanged even with the mix control in idle cutoff. Even if there is
some
initial vapor produced it is purged back into the tank and is not a
factor.
I assume one runs the electric pump long enough to cool things down a
little. Worked for me at 6,000ft in 110F heat soaked aircraft many times
when other acft ran the batterys down trying to start.
Once properly cooled enough and considering that need not be much, with
the
pressure supplied by the electric pump it eliminates vapor lock during
the
critical start. There is always electric pump pressure at the inlet and
thruout the mech pump and mix assy from the electric pump during its
operation and thus no possible suction to allow vapor lock at the inlet
of
the pump.
I hope you review the Cont system (in the 1971 book) was referring to
and
not some later system.
The key to my point is circulation of fuel works and it worked for me
too
many times to count and the Bendix system design did not permit this and
was, in most pilots (I have talked to) experience hard to 'hot' start.
If you have an alternative why there is such a dramatic difference in
the
Bendix system VS the Cont system as used in the S35 ( I am specifically
talking about that system and not other versions) I would be interested.
I
found hot starts to be a non event! I have never been able to hot start
the
Bendix system with out lots of cranking as one often makes a hot start
into
a severely flooded engine start. I have never met a pilot that did not
have
problems with the Bendix system and most failed to accept that in the
S35 it
could be a non event.
To me as an engineer and mechanic the key is the ability to replace most
of
the hot fuel and also cool most of the fuel system prior to any attempt
to
crank the engine.
Paul
----- Original Message -----
From: "George Braly" <gwbraly(at)gami.com>
Subject: RE: AeroElectric-List: Re: Cont VS Bendix injection systems
>
>
> Paul,
>
> The TCM starting issue has virtually nothing to do with "flushing hot
> fuel from the system."
>
> Rather, it has everything to do with the temperature of the internal
> components of the mechanical fuel pump that come into contact with new
> fuel from the tank.
>
> If those components are hot enough to flash to vapor a significant
> portion of the hydrocarbon components of the new incoming fuel stream
-
> - then there will be a "bloom" of vapor as the new fuel hits the
inlet
> portion of the mechanical fuel pump - - which will then nicely suffer
a
> classic vapor lock as the pump inlet "suction" is relieved by the
bloom
> of fuel vapor and the pump is no longer able to pull (suck) fuel
uphill
> to the inlet of the mechanical pump.
>
> It is not helpful to an understanding of the problem to try to deal
with
> anything that happens downstream of that point - - as frankly, "HOT"
> downstream of the mechanical pump is usually helpful to the final
> result, not harmful.
>
> If, during cranking or subsequent operation, a gram of fuel vaporizes
> in one of the small stainless fuel lines, it is still a gram of fuel
> that ends up going into the cylinder induction plumbing and eventually
> into the cylinder and burning just like it would if it were liquid
when
> it entered or exited the fuel injector.
>
> Regards, George
>
==
==
==
==
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Cont VS Bendix injection systems//auto engine issues |
Interesting but I fail to see how the system I had (S-35) COULD do that even
with the hot fuel, is there a real difference to fuel that is in the wings
and heated just from sitting around? Seems either way it can be just as hot
under the right conditions.
The single speed aux pump system I refer to has the same fuel pressure from
the electric pump (as the engine driven pump) that is NOT heated from the
engine.
There apparently can be a problem with either no electric pump or the pump
on LO (what ever that pressure is) during close to the ground ops.
You say the pump on HI did restart the engine so I suggest that if your
system had been designed for full aux pump pressure operation during TO
there would not have been critical Vapor lock (If any at all).
In my opinion the Bendix system would have locked under similar conditions.
Or any system that did not have the aux pump both be able to purge the
system as well as provide sufficent fuel pressure to the engine mounted fuel
pump etc.
Bottom line; with fuel vapor increasing in todays fuel, perhaps some
relooking is needed. Above ground tanks is something I have not considered
as a big concern but I see your point.
Those using todays auto fuel may have problems if the fuel is ever allowed
to be sucked into the pump. The sucking action lowers the pressure and
allows vapor lock.
In fact there have been several accidents in the last year from poorly
designed fuel delivery systems in auto engine conversions. The ones I have
looked into all have a common element, vapor lock due to the design that
allows the pump to suck at the inlet allowing the hi vapor pressure fuel to
vaporize.
The automotive industry solves this problem with intank fuel pumps,
something these auto conversions did not have, nor did they have a header
tank to provide sufficent fuel pressure to prevent pump inlet sucking :-)
Sadly I expect some more accidents, this summer, in experimental auto
conversion powered aircraft from a widely advertised conversion (with a
major fuel delivery system design problem using auto fuel in particular).
But that is a completely different subject and as this one off the lists
purpose.
Thanks for sharing your experience!
Paul
----- Original Message -----
From: "George Braly" <gwbraly(at)gami.com>
Subject: RE: AeroElectric-List: Re: Cont VS Bendix injection systems
>
>
> TCM has a basic system that requires an electric boost pump.
>
> Cessna , Beech and others, at different times have provided either
> single speed boost pumps or two speed boost pumps, depending pretty much
> on which side of the bed some engineer and the FAA got up on the day the
> decision was made.
>
> The two speed pumps are very nice to have and very useful.
>
> I have seen a vapor lock so bad on a normally aspirated IO-550 that took
> off from Bullhead City, Az - - with 100+F new fuel (above ground tanks)
> loaded into the airplane - - that it vapor locked about 120 seconds
> after takeoff.
>
> HARD vapor lock.
>
> LOW boost did not even touch the problem.
>
> It took FULL RICH and HIGH boost to get the engine running again before
> we hit the terrain.
>
> One then current space shuttle mission specialist on board (PIC), me,
> and two teenagers.
>
> It made for some interesting Crew Resource Management.
>
> Regards, George
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Paul
> Messinger
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: Re: Cont VS Bendix injection systems
>
>
>
> I think you missed my point.
>
> I agree with much of your comment.
>
> However; My point is that the secret is cooling the mechanical pump with
> cold fuel from the cold electric pump. Something not possible with the
> Bendix system. Fuel from the electric pump is pressurized above vapor
> pressure and does not vaporize at the hot engine pump. Further the cool
> fuel
> is pushed past the pump into the mixture assy where it is also cooled
> and
> exchanged even with the mix control in idle cutoff. Even if there is
> some
> initial vapor produced it is purged back into the tank and is not a
> factor.
> I assume one runs the electric pump long enough to cool things down a
> little. Worked for me at 6,000ft in 110F heat soaked aircraft many times
> when other acft ran the batterys down trying to start.
>
> Once properly cooled enough and considering that need not be much, with
> the
> pressure supplied by the electric pump it eliminates vapor lock during
> the
> critical start. There is always electric pump pressure at the inlet and
> thruout the mech pump and mix assy from the electric pump during its
> operation and thus no possible suction to allow vapor lock at the inlet
> of
> the pump.
>
> I hope you review the Cont system (in the 1971 book) was referring to
> and
> not some later system.
>
> The key to my point is circulation of fuel works and it worked for me
> too
> many times to count and the Bendix system design did not permit this and
> was, in most pilots (I have talked to) experience hard to 'hot' start.
>
> If you have an alternative why there is such a dramatic difference in
> the
> Bendix system VS the Cont system as used in the S35 ( I am specifically
> talking about that system and not other versions) I would be interested.
> I
> found hot starts to be a non event! I have never been able to hot start
> the
> Bendix system with out lots of cranking as one often makes a hot start
> into
> a severely flooded engine start. I have never met a pilot that did not
> have
> problems with the Bendix system and most failed to accept that in the
> S35 it
> could be a non event.
>
> To me as an engineer and mechanic the key is the ability to replace most
> of
> the hot fuel and also cool most of the fuel system prior to any attempt
> to
> crank the engine.
>
> Paul
>
> ----- Original Message -----
> From: "George Braly" <gwbraly(at)gami.com>
> To:
> Subject: RE: AeroElectric-List: Re: Cont VS Bendix injection systems
>
>
>
> >
> >
> > Paul,
> >
> > The TCM starting issue has virtually nothing to do with "flushing hot
> > fuel from the system."
> >
> > Rather, it has everything to do with the temperature of the internal
> > components of the mechanical fuel pump that come into contact with new
> > fuel from the tank.
> >
> > If those components are hot enough to flash to vapor a significant
> > portion of the hydrocarbon components of the new incoming fuel stream
> -
> > - then there will be a "bloom" of vapor as the new fuel hits the
> inlet
> > portion of the mechanical fuel pump - - which will then nicely suffer
> a
> > classic vapor lock as the pump inlet "suction" is relieved by the
> bloom
> > of fuel vapor and the pump is no longer able to pull (suck) fuel
> uphill
> > to the inlet of the mechanical pump.
> >
> > It is not helpful to an understanding of the problem to try to deal
> with
> > anything that happens downstream of that point - - as frankly, "HOT"
> > downstream of the mechanical pump is usually helpful to the final
> > result, not harmful.
> >
> > If, during cranking or subsequent operation, a gram of fuel vaporizes
> > in one of the small stainless fuel lines, it is still a gram of fuel
> > that ends up going into the cylinder induction plumbing and eventually
> > into the cylinder and burning just like it would if it were liquid
> when
> > it entered or exited the fuel injector.
> >
> > Regards, George
> >
>
>
> ==
> ==
> ==
> ==
>
>
________________________________________________________________________________
| From: | "Steve Sampson" <SSampson.SLN21(at)london.edu> |
| Subject: | ND Alternator repair |
Bob, interesting that you say failed ND alternators are very rare. Mine is
DOA on arrival from VANS and there is another builder on this list with the
same problem. Now David Chalmers has a problem also. Is it in fact true or
are we justa statistical blip?
Thanks, Steve.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Robert
L. Nuckolls, III
Subject: Re: AeroElectric-List: ND Alternator repair
>
>
>
>I just removed my failed ND alternator part number 100211-1411. I assume
>the regulator or diodes have failed. Where can I get replacement parts? Is
>this an easy repair or should I take it to a pro? Any advice appreciated.
Achieving the best rework of an alternator assumes you
have the skills, tools and/or the inclination to acquire
them. Given that ND alternator failures are very rare, you
can't depend on your own project offering lots of opportunities
for learning. Further, the price of a new-rebuild from the
car parts stores is so reasonable, it's difficult to justify
a DIY repair for any reason other that academic satisfaction.
Return on investment of time is poor and risks are higher.
However, if working on it yourself is attractive to you,
check for repair parts at http://www.alternatorparts.com
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
---
Incoming mail is certified Virus Free.
---
________________________________________________________________________________
| Subject: | Cont VS Bendix injection systems//auto engine issues |
| From: | "George Braly" <gwbraly(at)gami.com> |
Fuel vapor pressure is not increasing in todays 100LL.
That is an old wive's tale.
It is a ASTM D-910 specification - - and all of the aviation gasolines
meet it, with some margin to spare.
Regards, Geoerge
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Paul
Messinger
Subject: AeroElectric-List: Cont VS Bendix injection systems//auto
engine issues
Interesting but I fail to see how the system I had (S-35) COULD do that
even
with the hot fuel, is there a real difference to fuel that is in the
wings
and heated just from sitting around? Seems either way it can be just as
hot
under the right conditions.
The single speed aux pump system I refer to has the same fuel pressure
from
the electric pump (as the engine driven pump) that is NOT heated from
the
engine.
There apparently can be a problem with either no electric pump or the
pump
on LO (what ever that pressure is) during close to the ground ops.
You say the pump on HI did restart the engine so I suggest that if your
system had been designed for full aux pump pressure operation during TO
there would not have been critical Vapor lock (If any at all).
In my opinion the Bendix system would have locked under similar
conditions.
Or any system that did not have the aux pump both be able to purge the
system as well as provide sufficent fuel pressure to the engine mounted
fuel
pump etc.
Bottom line; with fuel vapor increasing in todays fuel, perhaps some
relooking is needed. Above ground tanks is something I have not
considered
as a big concern but I see your point.
Those using todays auto fuel may have problems if the fuel is ever
allowed
to be sucked into the pump. The sucking action lowers the pressure and
allows vapor lock.
In fact there have been several accidents in the last year from poorly
designed fuel delivery systems in auto engine conversions. The ones I
have
looked into all have a common element, vapor lock due to the design that
allows the pump to suck at the inlet allowing the hi vapor pressure fuel
to
vaporize.
The automotive industry solves this problem with intank fuel pumps,
something these auto conversions did not have, nor did they have a
header
tank to provide sufficent fuel pressure to prevent pump inlet sucking
:-)
Sadly I expect some more accidents, this summer, in experimental auto
conversion powered aircraft from a widely advertised conversion (with a
major fuel delivery system design problem using auto fuel in
particular).
But that is a completely different subject and as this one off the lists
purpose.
Thanks for sharing your experience!
Paul
----- Original Message -----
From: "George Braly" <gwbraly(at)gami.com>
Subject: RE: AeroElectric-List: Re: Cont VS Bendix injection systems
>
>
> TCM has a basic system that requires an electric boost pump.
>
> Cessna , Beech and others, at different times have provided either
> single speed boost pumps or two speed boost pumps, depending pretty
much
> on which side of the bed some engineer and the FAA got up on the day
the
> decision was made.
>
> The two speed pumps are very nice to have and very useful.
>
> I have seen a vapor lock so bad on a normally aspirated IO-550 that
took
> off from Bullhead City, Az - - with 100+F new fuel (above ground
tanks)
> loaded into the airplane - - that it vapor locked about 120 seconds
> after takeoff.
>
> HARD vapor lock.
>
> LOW boost did not even touch the problem.
>
> It took FULL RICH and HIGH boost to get the engine running again
before
> we hit the terrain.
>
> One then current space shuttle mission specialist on board (PIC), me,
> and two teenagers.
>
> It made for some interesting Crew Resource Management.
>
> Regards, George
>
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Paul
> Messinger
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: Re: Cont VS Bendix injection systems
>
>
>
> I think you missed my point.
>
> I agree with much of your comment.
>
> However; My point is that the secret is cooling the mechanical pump
with
> cold fuel from the cold electric pump. Something not possible with the
> Bendix system. Fuel from the electric pump is pressurized above vapor
> pressure and does not vaporize at the hot engine pump. Further the
cool
> fuel
> is pushed past the pump into the mixture assy where it is also cooled
> and
> exchanged even with the mix control in idle cutoff. Even if there is
> some
> initial vapor produced it is purged back into the tank and is not a
> factor.
> I assume one runs the electric pump long enough to cool things down a
> little. Worked for me at 6,000ft in 110F heat soaked aircraft many
times
> when other acft ran the batterys down trying to start.
>
> Once properly cooled enough and considering that need not be much,
with
> the
> pressure supplied by the electric pump it eliminates vapor lock during
> the
> critical start. There is always electric pump pressure at the inlet
and
> thruout the mech pump and mix assy from the electric pump during its
> operation and thus no possible suction to allow vapor lock at the
inlet
> of
> the pump.
>
> I hope you review the Cont system (in the 1971 book) was referring to
> and
> not some later system.
>
> The key to my point is circulation of fuel works and it worked for me
> too
> many times to count and the Bendix system design did not permit this
and
> was, in most pilots (I have talked to) experience hard to 'hot' start.
>
> If you have an alternative why there is such a dramatic difference in
> the
> Bendix system VS the Cont system as used in the S35 ( I am
specifically
> talking about that system and not other versions) I would be
interested.
> I
> found hot starts to be a non event! I have never been able to hot
start
> the
> Bendix system with out lots of cranking as one often makes a hot start
> into
> a severely flooded engine start. I have never met a pilot that did not
> have
> problems with the Bendix system and most failed to accept that in the
> S35 it
> could be a non event.
>
> To me as an engineer and mechanic the key is the ability to replace
most
> of
> the hot fuel and also cool most of the fuel system prior to any
attempt
> to
> crank the engine.
>
> Paul
>
> ----- Original Message -----
> From: "George Braly" <gwbraly(at)gami.com>
> To:
> Subject: RE: AeroElectric-List: Re: Cont VS Bendix injection systems
>
>
>
> >
> >
> > Paul,
> >
> > The TCM starting issue has virtually nothing to do with "flushing
hot
> > fuel from the system."
> >
> > Rather, it has everything to do with the temperature of the
internal
> > components of the mechanical fuel pump that come into contact with
new
> > fuel from the tank.
> >
> > If those components are hot enough to flash to vapor a significant
> > portion of the hydrocarbon components of the new incoming fuel
stream
> -
> > - then there will be a "bloom" of vapor as the new fuel hits the
> inlet
> > portion of the mechanical fuel pump - - which will then nicely
suffer
> a
> > classic vapor lock as the pump inlet "suction" is relieved by the
> bloom
> > of fuel vapor and the pump is no longer able to pull (suck) fuel
> uphill
> > to the inlet of the mechanical pump.
> >
> > It is not helpful to an understanding of the problem to try to deal
> with
> > anything that happens downstream of that point - - as frankly,
"HOT"
> > downstream of the mechanical pump is usually helpful to the final
> > result, not harmful.
> >
> > If, during cranking or subsequent operation, a gram of fuel
vaporizes
> > in one of the small stainless fuel lines, it is still a gram of
fuel
> > that ends up going into the cylinder induction plumbing and
eventually
> > into the cylinder and burning just like it would if it were liquid
> when
> > it entered or exited the fuel injector.
> >
> > Regards, George
> >
>
>
> ==
> ==
> ==
> ==
>
>
==
==
==
==
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)olypen.com> |
| Subject: | Re: Cont VS Bendix injection systems//auto engine issues |
I know.
I often forget that while auto fuel is popular with "WE" auto engine
converters its not always assummed by others its part of "FUEL". And sadly
its a moving target even to contents that can dissolve coatings etc.
Sorry for the confusion.
Paul
----- Original Message -----
From: "George Braly" <gwbraly(at)gami.com>
> Fuel vapor pressure is not increasing in todays 100LL.
>
> That is an old wive's tale.
>
> It is a ASTM D-910 specification - - and all of the aviation gasolines
> meet it, with some margin to spare.
>
> Regards, Geoerge
________________________________________________________________________________
| From: | Tammy and Mike Salzman <arrow54t(at)yahoo.com> |
| Subject: | Alternator Field connector stud |
Hi there,
I broke the stud where the alternator field wire connects to my Kelly
Aerospace alternator. (Contintntal IO-550) Anyone have a suggestion
where I can find a replacement? Kelly Aerospace wants $81 for a new
brush holder assembly, but I only need the stud. Of course they don't
sell just the stud. It resembles a carriage bolt, but smaller than
I've ever seen available locally. I think it may be about a #6 or #8
and about 1" long.
Thanks,
Mike Salzman
Fairfield, CA
Lancair ES
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Alternator Field connector stud |
Tammy and Mike Salzman wrote:
>
>Hi there,
>
>I broke the stud where the alternator field wire connects to my Kelly
>Aerospace alternator. (Contintntal IO-550) Anyone have a suggestion
>where I can find a replacement? Kelly Aerospace wants $81 for a new
>brush holder assembly, but I only need the stud. Of course they don't
>sell just the stud. It resembles a carriage bolt, but smaller than
>I've ever seen available locally. I think it may be about a #6 or #8
>and about 1" long.
>
>Thanks,
>Mike Salzman
>Fairfield, CA
>Lancair ES
>
Most medium sized cities have at least one ' Bolt & Screw'
distributor (Jackson MS has three). They always have stuff you'd never
see in a retail hardware store. You can usually walk in with the broken
part, looking pitiful (or get your wife to do it) & they will feel sorry
for you & find what you need.
Or you could try:
http://www.mcmaster.com/
Charlie
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Alternator Field connector stud |
Tammy and Mike Salzman wrote:
>
>Hi there,
>
>I broke the stud where the alternator field wire connects to my Kelly
>Aerospace alternator. (Contintntal IO-550) Anyone have a suggestion
>where I can find a replacement? Kelly Aerospace wants $81 for a new
>brush holder assembly, but I only need the stud. Of course they don't
>sell just the stud. It resembles a carriage bolt, but smaller than
>I've ever seen available locally. I think it may be about a #6 or #8
>and about 1" long.
>
>Thanks,
>Mike Salzman
>Fairfield, CA
>Lancair ES
>
Forgot to mention:
There's a pretty high probability that if you show the alt. to your
local auto-electric shop, they can sell you the brush holder for a lot
less money.
Of course, if it's for a factory a/c, I would *never* recommend doing
that.....
Charlie
________________________________________________________________________________
| From: | "David Schaefer" <dschaefer1(at)kc.rr.com> |
| Subject: | LED / Overvoltage Indicator |
Bob .. I've just finished wiring the low voltage lights on both my B&C
alternators.
I used LEDs with a 470 ohm 1/2 watt resister in front of the plus-side per
the manufacturer's instructions to protect the LEDs. However, when the low
voltage condition is gone, the LEDs dim but don't go out completely!! I
thought there was an electrical problem until I realized that the voltage
regulator 'thinks' the lamps are out.
What can I do to completely shut off the LEDs once the voltage regulators
indicate there is no longer an error condition? Is this because they
usually use incandescent lights?
Regards,
David
________________________________________________________________________________
| Subject: | ND Alternator repair |
| From: | "David Chalmers" <David(at)ChalmersFamily.com> |
Thanks everyone for the suggestions. I found a local alternator rebuilder who took
a look at it. Replaced the brushes and that seemed to fix it. Total cost $50.
Dave Chalmers
Redmond, WA
-----Original Message-----
From: Ken [mailto:klehman(at)albedo.net]
Subject: Re: AeroElectric-List: ND Alternator repair
You might want to check the slip rings on the armature for wear before
investing in a rebuild kit. Sometimes the slip rings are worn to the
point that it makes more sense to let a rebuilder have it than to just
replace the diodes, regulator, and brushes with a parts kit. A good
rebuilder will replace the slip rings. That will also confirm that you
can remove the bolts that hold the case together. Sometimes the bolts
are seized pretty tight but otherwise I have always found parts kits to
be easy to install. Sometimes you have to get creative and use a piece
of string or something to hold the brushes retracted for assembly.
Rebuilders use the part number you mentioned whereas the parts counter
usually wants to know what vehicle it came out of.
Ken
>>
>>
>>
>>I just removed my failed ND alternator part number 100211-1411. I assume
>>the regulator or diodes have failed. Where can I get replacement parts? Is
>>this an easy repair or should I take it to a pro? Any advice appreciated.
>>
>>
________________________________________________________________________________
| From: | f1rocket(at)comcast.net |
| Subject: | Re: LED / Overvoltage Indicator |
David,
You need another resister across the light to prevent current leakage in the off
state. You can reference this electrical diagram:
http://f1rocket.home.comcast.net/Alternator.pdf
Randy
F1 Rocket
>
> Bob .. I've just finished wiring the low voltage lights on both my B&C
> alternators.
>
> I used LEDs with a 470 ohm 1/2 watt resister in front of the plus-side per
> the manufacturer's instructions to protect the LEDs. However, when the low
> voltage condition is gone, the LEDs dim but don't go out completely!! I
> thought there was an electrical problem until I realized that the voltage
> regulator 'thinks' the lamps are out.
>
> What can I do to completely shut off the LEDs once the voltage regulators
> indicate there is no longer an error condition? Is this because they
> usually use incandescent lights?
>
> Regards,
>
> David
>
>
>
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | DIY crowbar OV module update |
A number of folks have elected to fabricate their own crowbar
over voltage protection modules per instructions published at:
http://www.aeroelectric.com/articles/crowbar.pdf
I'm being asked in increasing numbers to assist builders in
trouble shooting non-working assemblies. I don't have uncommitted
time to indulge myself in this activity so I've updated
plans for the crowbar OVM to include a trouble shooting guide.
While crafting the revised instructions, some refinements
to the circuit were made. If you have an OVM crafted to the
older plans which is functioning, there is no need to immediately
"update" your installed unit. However, new units under construction
and older units removed for the annual bench test should
be updated to the latest drawings as published above.
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
| From: | Michel Therrien <mtherr(at)yahoo.com> |
| Subject: | Re: DIY crowbar OV module update |
Does this affect the purchased version of OVM? (I
bought the OVM-14 few years ago).
--- "Robert L. Nuckolls, III"
wrote:
> Nuckolls, III"
>
>
> While crafting the revised instructions, some
> refinements
> to the circuit were made. If you have an OVM crafted
> to the
> older plans which is functioning, there is no need
> to immediately
> "update" your installed unit. However, new units
=====
----------------------------
Michel Therrien CH601-HD, C-GZGQ
http://mthobby.pcperfect.com/ch601
http://www.zenithair.com/bldrlist/profiles/mthobby
http://pages.infinit.net/mthobby
__________________________________
http://promotions.yahoo.com/new_mail
________________________________________________________________________________
| From: | CardinalNSB(at)aol.com |
| Subject: | Re: does length matter (vor coax hookup..) |
If I read the archives correctly, the "balun" used in my 1968 Cessna is
unnecessary.
Is there any "correct length" that the split of the coax inner and shield
should be made?
thanks, skip simpson
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: does length matter (vor coax hookup..) |
CardinalNSB(at)aol.com wrote:
>
> If I read the archives correctly, the "balun" used in my 1968 Cessna is
> unnecessary.
It may be unnecessary but it is a good idea to do something. It will help to keep
the pattern of the antenna as symmetrical as possible. Coiling the coax into
four or five turns about 3"-4" in diameter will work too and it is easier
to do than carefully measuring and cutting coax for a balun.
> Is there any "correct length" that the split of the coax inner and shield
> should be made?
It should be a short as possible commensurate with good mechanical connections
with strain relief.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | "Randy Pflanzer" <f1rocket(at)comcast.net> |
| Subject: | Music Volume Question |
Today was a big day. I did the smoke test on my wiring and all the smoke
stayed inside. That's a big relief.
I do have one issue. The volume on my MP/3 players is barely audable via my
PM3000 intercom. Do I need an amplifier for the MP/3 player or is there a
pot adjustment somewhere on the PM3000 to increase the volume? A review of
the available documentation did not yield an answer.
Randy
F1 Rocket
http://f1rocket.home.comcast.net/
________________________________________________________________________________
| From: | "Brian Kraut" <brian.kraut(at)engalt.com> |
| Subject: | Music Volume Question |
I don't know about the PM3000, but check the manual for your MP3 player. My
XM radio has a software volume adjustment in the menus that I had to turn
all the way up.
Brian Kraut
Engineering Alternatives, Inc.
www.engalt.com
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Randy
Pflanzer
Subject: AeroElectric-List: Music Volume Question
Today was a big day. I did the smoke test on my wiring and all the smoke
stayed inside. That's a big relief.
I do have one issue. The volume on my MP/3 players is barely audable via my
PM3000 intercom. Do I need an amplifier for the MP/3 player or is there a
pot adjustment somewhere on the PM3000 to increase the volume? A review of
the available documentation did not yield an answer.
Randy
F1 Rocket
http://f1rocket.home.comcast.net/
________________________________________________________________________________
| From: | "Bill Hibbing" <n744bh(at)bellsouth.net> |
| Subject: | Re: Music Volume Question |
Check your squelch adjustments on the intercom. If one squelch is open it
would have this effect. I had the same problem and found that the co
pilot's squelch was not set high enough. Turning a knob beat the heck out
of tearing into the system.
Bill
Glasair
----- Original Message -----
From: "Randy Pflanzer" <f1rocket(at)comcast.net>
Subject: AeroElectric-List: Music Volume Question
>
> Today was a big day. I did the smoke test on my wiring and all the smoke
> stayed inside. That's a big relief.
>
> I do have one issue. The volume on my MP/3 players is barely audable via
my
> PM3000 intercom. Do I need an amplifier for the MP/3 player or is there a
> pot adjustment somewhere on the PM3000 to increase the volume? A review
of
> the available documentation did not yield an answer.
>
> Randy
> F1 Rocket
> http://f1rocket.home.comcast.net/
>
>
________________________________________________________________________________
| From: | f1rocket(at)comcast.net |
| Subject: | Low Audio Output |
I've been wandering around in the archives for a couple of hours searching for
resolutions to my problem of low audio output by my MP3 player into my PM3000
intercom. What's amazing is the number of people that have the problem but the
lack of documentation on what solved it.
I've been able to determine that the power output of the portable device in not
sufficient to drive the headphones or the intercom music circuit. Therefore,
an in-line amplifier is required.
Some folks have suggested The Muse, but with limited success. Some folks have
offered amplfiers, but their web sites no longer have the product. A Radio Shack
part (33-1109) has also been offered but no record of whether it worked or
not. Finally, Bob offers a mini-project to build your own. That appears a bit
much for me to complete.
Okay, so how have folks solved the problem? Do the small battery operated in-line
amplifiers work? I hate to bring another battery device into the cockpit.
Are there other products out there? Does someone offer Bob's amplifier already
built?
Inquiring minds want to know.
Randy
F1 Rocket
I've been wandering around in the archives for a couple of hours searching for
resolutions to my problem of low audio output by my MP3 player into my PM3000
intercom. What's amazing is the number of people that have the problem but the
lack of documentation on what solved it.
I've been able to determine that the power output of the portable device in not
sufficient to drive the headphones or the intercom music circuit. Therefore,
an in-line amplifier is required.
Some folks have suggested The Muse, but with limited success. Some folks have offered
amplfiers, but their web sites no longer have the product. A Radio Shack
part (33-1109) has also been offered but no record of whether it worked or not.
Finally, Bob offers a mini-project to build your own. That appears a bit much
for me to complete.
Okay, so how have folks solved the problem? Do the small battery operated in-line
amplifiers work? I hate to bring another battery device into the cockpit. Are
there other products out there? Does someone offer Bob's amplifier already
built?
Inquiring minds want to know.
Randy
F1 Rocket
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Low Audio Output |
f1rocket(at)comcast.net wrote:
> I've been able to determine that the power output of the portable
> device in not sufficient to drive the headphones or the intercom
> music circuit. Therefore, an in-line amplifier is required.
Actually, power is not the issue. Most audio panels have a relatively high input
impedance for the music input so you really need voltage gain, not power gain.
A pair of op-amps would give enough gain to accomplish what you want.
OTOH, has anybody talked to the maker of the audio panel? This seems to be a pretty
common problem. OTOH, I have no problem with my PMA-7000 audio panels in
my airplanes. My iPod seems to have enough voltage drive to achieve a comfortable
listening level.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | "Ross Mickey" <rmickey(at)ix.netcom.com> |
| Subject: | Low Audio Output |
Brian,
Fortunately I had just purchased a 6000 series PS Engineering audio
panel when this whole issue of low volume levels was being discussed on
the list. The solution to the low volume issue by PS Engineering was to
design the 7000 series. Since I had not opened the box on my 6000
series, I was able to trade it in for a 7000. The main difference, in
this regard, is the 7000 series has a separate volume control for audio
inputs and the 6000 does not. Those with the 6000 series are left to
solve the problem with an add-on.
Ross Mickey
N9PT
-----Original Message-----
OTOH, has anybody talked to the maker of the audio panel? This seems to
be a pretty common problem. OTOH, I have no problem with my PMA-7000
audio panels in my airplanes. My iPod seems to have enough voltage
drive to achieve a comfortable listening level.
________________________________________________________________________________
| From: | f1rocket(at)comcast.net |
| Subject: | Re: Low Audio Output |
>A pair of op-amps would give enough gain to accomplish what you want.
>
Sorry for being dense, but can you translate that into a product recommendation?
Thanks.
Randy
F1 Rocket
A pair of op-amps would give enough gain to accomplish what you want.
Sorry for being dense, but can you translate that into a product recommendation?
Thanks.
Randy
F1 Rocket
________________________________________________________________________________
| From: | "John Slade" <sladerj(at)bellsouth.net> |
| Subject: | Low Audio Output |
> >A pair of op-amps would give enough gain to accomplish what you want.
> >
> Sorry for being dense, but can you translate that into a product
> recommendation? Thanks.
>
> Randy
> F1 Rocket
Don't feel dense, Randy.
I've had the same problem for 3 months, and have asked the same question.
I'm following this thread hoping (this time) for a solution. Other similar
threads have lead nowhere. I don't want to build anything. I just want to
buy some simple, cheap gizmo that'll boost the audio on my plug in portable
CD player so I can actually hear it.
Regards,
John Slade
Turbo Rotary Cozy IV
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Low Audio Output |
f1rocket(at)comcast.net wrote:
>
>
>>A pair of op-amps would give enough gain to accomplish what you want.
>>
>
> Sorry for being dense, but can you translate that into a product recommendation?
Thanks.
Now it is my turn to be sorry. I spoke before thinking. I was thinking in terms
of building something but you are looking for an off-the-shelf solution. What
you need is a preamp. And, sorry, I can't think of any that are a) cheap,
b) small, and c) powered by 12V.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | "John Slade" <sladerj(at)bellsouth.net> |
| Subject: | Low Audio Output |
> > Sorry for being dense, but can you translate that into a
> product recommendation? Thanks.
How about this little baby?
2x7W 12V Walkman Stereo Amplifier Kit $29 fully assembled.
http://www.hobbytron.net/CK154A.html?AID=10289758&PID=1117139
Would this do the job for us?
John Slade
________________________________________________________________________________
| From: | Rick Girard <fly.ez(at)verizon.net> |
| Subject: | Re: Low Audio Output |
I realize this isn't exactly off the shelf, but what about the
amplifiers in cheap computer speakers? Go to a PC recycler, or take the
wife garage saleing for a day and buy a pair of computer speakers for a
dollar. There is also the option of buying amplified speakers made
specifically for walk men and ipod style personal stereos, but they're
not likely to be a buck. Tear the guts out, put it in an altoid box and
double back tape it out of the way. Just a PBI.
Rick Girard
________________________________________________________________________________
| From: | "royt.or(at)netzero.com" <royt.or(at)NetZero.com> |
| Subject: | RE: Low Audio Output |
I've been using a Radio Shack headphone booster (pn 33-1109)and portable CD/MP3 player in my plane with Garmin 340 audio panel, Peltor 7004 headset and/or Lightspeed XL20 headset. This has been marginal but not ideal. I've purchased parts to build HeadBanger headphone amp. This is also available prebuilt. See http://www.minidisc.org/headbanger.html I plan to run this from the plane with a 12v to 9v powersupply.
I recently installed a Headsets Inc ANR kit in my Peltor. See http://www.headsetsinc.com/ The volume output of the upgraded headset is much louder. If I always flew solo, I would be very happy with the portable player, Radio Shack booster and ANR'ed Peltors. I'm still planning to build the amp and power supply. I'll power the Headsets Inc ANR from the same power supply.
I'll report back when I have completed and installed the HeadBanger amp.
(Garmin also say's there are four surface mount resistors which can be removed
to increase the external audio volume and may increase the noise. My local shop
quote to do this seemed out rageous. Something like $150.)
Regards,
Roy
N601RT: CH601HDS, nose gear, Rotax 912ULS, All electric, IFR equipped, 230hrs,
320 landings
________________________________________________________________________________
| From: | Richard Tasker <retasker(at)optonline.net> |
| Subject: | Re: Low Audio Output |
Great but not what he needs. This would be perfect if one wanted to
take the output of the MP3 player and drive some speakers, but would not
work to just amplify the voltage to feed into the PS3000.
Sorry, Dick Tasker
John Slade wrote:
>
>
>
>>>Sorry for being dense, but can you translate that into a
>>>
>>>
>>product recommendation? Thanks.
>>
>>
>How about this little baby?
> 2x7W 12V Walkman Stereo Amplifier Kit $29 fully assembled.
>
> http://www.hobbytron.net/CK154A.html?AID=10289758&PID=1117139
>
>Would this do the job for us?
>John Slade
>
>
>
>
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Low Audio Output |
John Slade wrote:
> How about this little baby?
> 2x7W 12V Walkman Stereo Amplifier Kit $29 fully assembled.
>
> http://www.hobbytron.net/CK154A.html?AID=10289758&PID=1117139
>
> Would this do the job for us?
Yes, it should.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Low Audio Output |
f1rocket(at)comcast.net wrote:
>
>I've been wandering around in the archives for a couple of hours searching for
resolutions to my problem of low audio output by my MP3 player into my PM3000
intercom. What's amazing is the number of people that have the problem but the
lack of documentation on what solved it.
>I've been able to determine that the power output of the portable device in not
sufficient to drive the headphones or the intercom music circuit. Therefore,
an in-line amplifier is required.
>Some folks have suggested The Muse, but with limited success. Some folks have
offered amplfiers, but their web sites no longer have the product. A Radio Shack
part (33-1109) has also been offered but no record of whether it worked or
not. Finally, Bob offers a mini-project to build your own. That appears a
bit much for me to complete.
>Okay, so how have folks solved the problem? Do the small battery operated in-line
amplifiers work? I hate to bring another battery device into the cockpit.
Are there other products out there? Does someone offer Bob's amplifier already
built?
>Inquiring minds want to know.
>Randy
>F1 Rocket
>
Here's the link to the RS 33-1109:
http://www.radioshack.com/images/ProductCatalog/Manuals/OME33-1109.pdf
40 mW is .8 volts into a 16 ohm load & isn't likely to do the trick. I'd
want at least 2-3 volts output to give myself a little wiggle room.
Just for grins, here are some audiophile quality headphone amps that
could be made to work, but might be a little higher quality than what
you need.
http://www.headphone.com/layout.php?topicID=3&subTopicID=27
This has more gain than you really need & still costs too much...
http://www.opamplabs.com/m9c.htm
Does the desire for plug&play arise out of the need for speed &
convenience, or 'fear of soldering'? FWIW, if you can wire your airplane
you can assemble a simple kit of electronic parts. If you just 'must
have' plug & play, I'll call our local A/V supplier tomorrow & see
what's available.
Charlie
(electronics tech in a former life)
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Low Audio Output |
My experience with similar devices says it will work just fine. It's
capable of just over 4 volts output (should be plenty to drive the
intercom) into 4 ohms & it shouldn't care if it sees ~600 ohms instead
of 4 ohms. The higher impedance reduces the load on the amplifier. As
an analogy, think of your 500 amp battery supplying power to a comm.
transmitter with a 5 amp current demand.
Just start with the source output level at a midrange setting & the
amp's input controls near minimum, then bring up the amp's volume
slowwwly while playing something through the source.
Charlie
Richard Tasker wrote:
>
>Great but not what he needs. This would be perfect if one wanted to
>take the output of the MP3 player and drive some speakers, but would not
>work to just amplify the voltage to feed into the PS3000.
>
>Sorry, Dick Tasker
>
>John Slade wrote:
>
>
>
>>
>>
>>
>>
>>
>>>>Sorry for being dense, but can you translate that into a
>>>>
>>>>
>>>>
>>>>
>>>product recommendation? Thanks.
>>>
>>>
>>>
>>>
>>How about this little baby?
>> 2x7W 12V Walkman Stereo Amplifier Kit $29 fully assembled.
>>
>> http://www.hobbytron.net/CK154A.html?AID=10289758&PID=1117139
>>
>>Would this do the job for us?
>>John Slade
>>
________________________________________________________________________________
| From: | "Richard E. Tasker" <retasker(at)optonline.net> |
| Subject: | Re: Low Audio Output |
Well, you are probably right. I am an electrical engineer :-) and
look at it as not the correct device for the intended purpose - to do a
little preamplification of his MP3 player to feed to his PM3000 intercom.
While either should work (if the problem has been stated correctly) I
would suggest that this would be a more appropriate solution (from the
same source):
http://www.hobbytron.net/vk2572.html
Dick Tasker
Charlie England wrote:
>
>My experience with similar devices says it will work just fine. It's
>capable of just over 4 volts output (should be plenty to drive the
>intercom) into 4 ohms & it shouldn't care if it sees ~600 ohms instead
>of 4 ohms. The higher impedance reduces the load on the amplifier. As
>an analogy, think of your 500 amp battery supplying power to a comm.
>transmitter with a 5 amp current demand.
>
>Just start with the source output level at a midrange setting & the
>amp's input controls near minimum, then bring up the amp's volume
>slowwwly while playing something through the source.
>
>Charlie
>
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Low Audio Output |
Richard Tasker wrote:
>
> Great but not what he needs. This would be perfect if one wanted to
> take the output of the MP3 player and drive some speakers, but would not
> work to just amplify the voltage to feed into the PS3000.
Ah, but it would. The amp has voltage gain and is a single-ended output, i.e.
output relative to ground rather than a bridged or balanced output. It should
work just fine.
OTOH, some of the other "headphone boosters" might be better but you will find
they are almost the same design.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Low Audio Output |
The only potential glitch I see with this one is the 1k ohm output
impedance, typical for circuits designed to drive home stereo components
with ~50k ohm input impedance. If the intercom has a 600 ohm input
impedance (fairly common in a/c & pro audio gear) this device might be
strained a bit to produce a clean signal. I haven't looked at the TL072
spec sheet; it might be more than capable of driving a 600 load with a
resistor change in the ouput, but the idea was plug & play.
If the intercom has a >10k ohm input impedance, you have indeed found a
better device for this purpose.
BTW, neither device appears to include a case or connectors, so some
soldering & parts chasing will likely still be required with either device.
Charlie
(not an engineer; just an old southern boy who used to build & repair
similar gadgets for concert sound systems)
Richard E. Tasker wrote:
>
>Well, you are probably right. I am an electrical engineer :-) and
>look at it as not the correct device for the intended purpose - to do a
>little preamplification of his MP3 player to feed to his PM3000 intercom.
>
>While either should work (if the problem has been stated correctly) I
>would suggest that this would be a more appropriate solution (from the
>same source):
>
>http://www.hobbytron.net/vk2572.html
>
>Dick Tasker
>
>Charlie England wrote:
>
>
>
>>
>>My experience with similar devices says it will work just fine. It's
>>capable of just over 4 volts output (should be plenty to drive the
>>intercom) into 4 ohms & it shouldn't care if it sees ~600 ohms instead
>>of 4 ohms. The higher impedance reduces the load on the amplifier. As
>>an analogy, think of your 500 amp battery supplying power to a comm.
>>transmitter with a 5 amp current demand.
>>
>>Just start with the source output level at a midrange setting & the
>>amp's input controls near minimum, then bring up the amp's volume
>>slowwwly while playing something through the source.
>>
>>Charlie
>>
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Low Audio Output |
Charlie England wrote:
> Just for grins, here are some audiophile quality headphone amps that
> could be made to work, but might be a little higher quality than what
> you need.
> http://www.headphone.com/layout.php?topicID=3&subTopicID=27
As an interesting offshoot of this discussion, has anyone considered the issue
of headphone audio quality? Since I have started carrying my iPod in the airplane
I have become much more interested in the quality of the headphone audio.
As a result, an interesting thing has occurred.
Several years back I popped for a LightSpeed 25XL headset for my wife in an attempt
to give her something she found quiet and comfortable. (They are very comfortable,
especially for women wearing earrings.) Since I flew more I found
myself often using her headset. OTOH, I didn't want to spend an ungodly amount
of money for every seat in the airplane so I popped for a set of LightSpeed
QFR headsets (no ANR) for passengers. These are supposed to be cheap headsets.
The problem is:
1. they provide better passive noise attenuation;
2. they have better audio quality.
I now find myself using the "cheap" LightSpeed QFR headsets in preference to the
25XLs. I have come to the conclusion after flying thousands of hours with ANR
headsets that they just aren't all that great. Give me a headset with lots
of passive noise attenuation and no active noise reduction (ANR) and I am much
happier.
BTW, this seems to hold true for the Bose and Telex DSP ANR systems as well.
Disclaimer: this is my personal preference. Your mileage may vary.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | "John Slade" <sladerj(at)bellsouth.net> |
| Subject: | Low Audio Output |
> http://www.hobbytron.net/CK154A.html?AID=10289758&PID=1117139
> would not work to just amplify the voltage to feed into the PS3000.
> Ah, but it would. The amp has voltage gain and is a single-ended ...
Thanks for all the input.
I ordered one. I'll report back on how well it handles the input to my RST
intercom.
John Slade
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Low Audio Output |
Charlie England wrote:
>
> The only potential glitch I see with this one is the 1k ohm output
> impedance, typical for circuits designed to drive home stereo components
> with ~50k ohm input impedance. If the intercom has a 600 ohm input
> impedance (fairly common in a/c & pro audio gear) this device might be
> strained a bit to produce a clean signal. I haven't looked at the TL072
> spec sheet; it might be more than capable of driving a 600 load with a
> resistor change in the ouput, but the idea was plug & play.
I used to drive Sennheiser headphones directly from the output of a TL071-based
preamp I designed. The TL072 is just dual TL071's in one DIP (without the DC
offset adjustment pins). It worked very well with only a very slight loss of
low-bass response. I was both surprised and pleased.
I think you will find that the input impedance of the music input of an intercom/audio-panel
is pretty high (greater than 10K at least). They are essentially
voltage inputs.
BTW, I used to make my living designing high-end audio amps and preamps back in
the late '70s.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | f1rocket(at)comcast.net |
| Subject: | Re: Low Audio Output |
Thanks for all the great responses. I really appreciate your willingness to share
your knowledge with all of us.
With the options that have been presented, there doesn't appear to be one that
is plug-n-play. Also, all of the options presented include a battery as the power
source to the amp. I had hoped to avoid that as well.
I believe there is a maketing opportunity out there for a box with two stereo jacks
and a power lead to 12V. Again, I can't believe that someone hasn't come
up with a solution somewhere that they would be willing to sell. If there is
anyone out there willing to put one of these together, please contact me off-line
at f1rocket(at)comcast.net. At this point in my project, I have more $$ than
time.
If that doesn't pan out, I'll probably buy an assembled card and take a stab at
putting something together. Again, my thanks to all who contributed to this
thread.
Randy
F1 Rocket
Thanks for all the great responses. I really appreciate your willingness to share
your knowledge with all of us.
With the options that have been presented,there doesn't appear to be one that is
plug-n-play.Also, all of the options presented include a battery as the power
source to the amp. I had hoped to avoid that as well.
I believe there is a maketing opportunity out there for abox with two stereo jacks
and a power lead to 12V. Again, I can't believe that someone hasn't come up
with a solution somewhere that they would be willing to sell. If there is anyone
out there willing to put one of these together, please contact me off-line
at f1rocket(at)comcast.net. At this point inmy project, I have more $$ than time.
If that doesn't pan out, I'll probably buy an assembled card andtake a stab at
putting something together. Again, my thanks to all who contributed to this thread.
Randy
F1 Rocket
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>On 05/07 11:23, Robert L. Nuckolls, III wrote:
>
> [...]
>
> > In the case originally cited, Garmin is specifying their
> > equipment to meet published performance with a maximum
> > of (8.8/100)*20 or 1.75 db of attenuation in both transmit
> > and receive paths. If you need a longer run, expect
> > a small (probably imperceptible) degradation or you can
> > go with a whippier coax like RG-223 where the losses
> > are 17 db per 100' so you can use up to 10.3 feet of
> > coax without degrading performance below the published
> > specifications.
>
> [...]
>
>Hi Bob,
>
>Now I KNOW I should wait to ask this question during your seminar
>here in Long Beach next month, but...
>
>After reading your post I decided to do some more research via
>the web, and to try to understand cabling and the various parameters
>and data provided there, because now it seems that there are
>more choices than RG400, RG223 for example. Of course, all I ended
>up doing was confusing myself even more. Several of the data parameters
>I found interesting to note were;
>
> a) Attenuation Ratings - at differing frequencies
> b) Power Ratings - at varying frequencies
> c) Cable physical properties - terminals, diameter, shielding,
> environmental factors, etc.
>
>Now I'm sure that each of these is very important when determining
>which cable to use for a specific purpose as transponders, comms
>and navs all have different requirements
>
>Of couse, I also found that the numbers a) and b) above varied
>greatly from site to site, some indicating nominal values and some
>with max values.
>
>Outwardly it would seem that you would be able to select a cable
>based upon all the above and it would be obvious which cable to use,
>provided you have accurate information.
>
>Can you recomment a source for accurate information and possible
>suggested cables for most applications?
>
>See you in a few weeks!
Questions in this arena have been tumbled about the List
and other places periodically for a long time. Many texts
like to make a big deal of wire selection . . . coax cables
included. Suffice it to say that if you went out and purchased
the CHEAPEST commercially available 50-ohm coax (probably RG-58
from Radio Shack) and used it to wire every antenna in your
airplane, it is unlikely that you'd sense any great degradation
of radio performance due to coax selection.
With the exception of GPS which operates at very high frequencies
and deals with very weak signals, there is a LOT of performance
headroom in radios that allows a broad range of coax materials
to function with no perceptible differences in performance as
the pilot/radio-operator.
If it were MY airplane, RG-400 or RG-142 would be the material
of choice MOSTLY because these are modern material coaxes
-AND- they're double shielded. From an RF performance perspective,
I'm not going to see big gains in radio functionality due to their
lower over the cheaper RG-58 styles of times gone by . . . like
WWII! RG-58 is polyethylene/PVC construction and single shield,
modern coaxes use cousins to teflon for insulation and have two
layers of silver plated shield - MUCH superior construction.
If one gets into an obsession about "losses", you can go to
coax specialty houses and purchase feedline materials with
very low losses at GPS and transponder frequencies but they're
several inches in diameter and weigh in with numbers like
4-5 pounds per foot.
Bottom line is this: For the runs typical of light aircraft
antenna installations, RG-400/142 losses are quite acceptable.
The coax is easy to get and nice to work with. If your coax
run on a GPS antenna has to be longer than 10 feet, there are
some premium coaxes like LMR-400 or 400U that you can purchase
in cut lengths with connectors already installed from
http://downeastmicrowave.com/
If for whatever reason you want to install a GPS antenna
at the top of a winglet on a canard pusher and need a 20'
feedline, then I'd spend some time picking a 'better' coax.
I put a 75-foot run of this stuff up to the roof at RAC
Missiles lab in Andover a couple of years ago and got a
nice GPS signal through it.
For all but the extreme cases, 400/142 is fine for
aviation antennas below 400 Mhz and any practical installation
in an SE aircraft. I wouldn't worry about transponder
installations out to 10' or so with 400/142 (radar signals
are really strong). If GPS needs to run out past 8 feet
then consider 223 or LRU-400. This is not intended
to argue with whatever advice the instruction manual for
a given radio has to offer. When in doubt, 223 or LRU-400
is ALWAYS going to work well.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: 11474 Buckle |
>
>Comments/Questions: I'm currently searching for a good tutorial on how to
>construct a wiring harness using waxed lacing tape as the bundling
>method. Do you know where I could find something along these lines? Your
>"Wire Bundle Tying Techniques" was very informative, thanks for writing it!
Most builders use string ties and tye-wraps interchangeably where
bundles are formed from a succession of individual ties. A "lost
art" for stringing a series of ties together on a single strand
of lacing cord is now illustrated in a new figure added to the
end of the article you cited above. See the bottom of the page
at:
http://www.aeroelectric.com/articles/cable_lace/cable_lace.html
Bob . . .
-----------------------------------------
( Experience and common sense cannot be )
( replaced with policy and procedures. )
( R. L. Nuckolls III )
-----------------------------------------
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: 11474 Buckle |
In a message dated 7/1/04 1:00:31 PM Central Daylight Time,
bob.nuckolls(at)cox.net writes:
Most builders use string ties and tye-wraps interchangeably where
bundles are formed from a succession of individual ties. A "lost
art" for stringing a series of ties together on a single strand
of lacing cord is now illustrated in a new figure added to the
end of the article you cited above. See the bottom of the page
at:
Good Afternoon Bob,
I tried that address and I get the same data that was at that site a week
ago. Am I missing something?
When I was going through the Aviation Electrician Mate School at JAX NATTC
in 1946, we were taught to tie wire bundles using a continuous length of
string. We used a knot at each tie that was the same as a rib stitch knot. The
idea was that the rib stitch knot would keep it from unraveling if it became
necessary to cut one of the ties. We were also told that running the string
continuously from tie to tie added some support to the entire bundle. I was
never too sure how much good that did, but as a brand new AEM, I did what I
was told!
Did you add some reference to the continuous tie method to your excellent
drawings and photos?
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Airpark LL22
Downers Grove, IL 60516
630 985-8502
________________________________________________________________________________
| Subject: | Re: 11474 Buckle |
| From: | "Larry Bowen" <Larry(at)BowenAero.com> |
Clear your browser cache and scroll all the way to the bottom.
-
Larry Bowen
Larry(at)BowenAero.com
http://BowenAero.com
BobsV35B(at)aol.com said:
>
>
> In a message dated 7/1/04 1:00:31 PM Central Daylight Time,
> bob.nuckolls(at)cox.net writes:
>
> Most builders use string ties and tye-wraps interchangeably where
> bundles are formed from a succession of individual ties. A "lost
> art" for stringing a series of ties together on a single strand
> of lacing cord is now illustrated in a new figure added to the
> end of the article you cited above. See the bottom of the page
> at:
>
>
> Good Afternoon Bob,
>
> I tried that address and I get the same data that was at that site a week
> ago. Am I missing something?
>
> When I was going through the Aviation Electrician Mate School at JAX NATTC
> in 1946, we were taught to tie wire bundles using a continuous length of
> string. We used a knot at each tie that was the same as a rib stitch
> knot. The
> idea was that the rib stitch knot would keep it from unraveling if it
> became
> necessary to cut one of the ties. We were also told that running the
> string
> continuously from tie to tie added some support to the entire bundle. I
> was
> never too sure how much good that did, but as a brand new AEM, I did what
> I
> was told!
>
> Did you add some reference to the continuous tie method to your excellent
> drawings and photos?
>
> Happy Skies,
>
> Old Bob
> AKA
> Bob Siegfried
> Ancient Aviator
> Stearman N3977A
> Brookeridge Airpark LL22
> Downers Grove, IL 60516
> 630 985-8502
>
>
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
Robert L. Nuckolls, III wrote:
> With the exception of GPS which operates at very high frequencies
> and deals with very weak signals, there is a LOT of performance
> headroom in radios that allows a broad range of coax materials
> to function with no perceptible differences in performance as
> the pilot/radio-operator.
Most GPS antennas are active and have amplifiers built-in. This overcomes the
problem with coax attenuation. Amazingly, 15' of old RG-58A/U works just fine
so there has to be a fair amount of gain in the antenna's preamp.
And, no, this is not to say I recommend RG-58, only that it works. RG-400 and
RG-142 are much superior from the point of view of longevity and consistency over
time.
I use LMR-400 for my 2.4GHz systems down here and they are outside in a tropical
marine environment, much worse than the environment in an aircraft and they
seem to hold up pretty well. That is what I would use for a long transponder
coax run.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | John Stevenson <johnstevenson31(at)yahoo.com> |
| Subject: | Re: AeroElectric-List Digest: 19 Msgs - 06/30/04 |
I will to no longer receive emials from AEROELECTRIC-LIST DIGEST.
Thank you
AeroElectric-List Digest Server wrote:
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Total Messages Posted Wed 06/30/04: 19
Today's Message Index:
----------------------
1. 10:00 AM - Low Audio Output (f1rocket(at)comcast.net)
2. 10:53 AM - Re: Low Audio Output (Brian Lloyd)
3. 11:29 AM - Re: Low Audio Output (Ross Mickey)
4. 12:49 PM - Re: Low Audio Output (f1rocket(at)comcast.net)
5. 01:06 PM - Re: Low Audio Output (John Slade)
6. 03:26 PM - Re: Low Audio Output (Brian Lloyd)
7. 03:46 PM - Re: Low Audio Output (John Slade)
8. 04:04 PM - Re: Low Audio Output (Rick Girard)
9. 04:05 PM - Re: Low Audio Output (royt.or(at)netzero.com)
10. 04:09 PM - Re: Low Audio Output (Richard Tasker)
11. 04:20 PM - Re: Low Audio Output (Brian Lloyd)
12. 04:30 PM - Re: Low Audio Output (Charlie England)
13. 05:05 PM - Re: Low Audio Output (Charlie England)
14. 06:12 PM - Re: Low Audio Output (Richard E. Tasker)
15. 06:36 PM - Re: Low Audio Output (Brian Lloyd)
16. 06:46 PM - Re: Low Audio Output (Charlie England)
17. 07:10 PM - Re: Low Audio Output (Brian Lloyd)
18. 07:10 PM - Re: Low Audio Output (John Slade)
19. 07:20 PM - Re: Low Audio Output (Brian Lloyd)
________________________________ Message 1 _____________________________________
From: f1rocket(at)comcast.net
Subject: AeroElectric-List: Low Audio Output
I've been wandering around in the archives for a couple of hours searching for
resolutions to my problem of low audio output by my MP3 player into my PM3000
intercom. What's amazing is the number of people that have the problem but the
lack of documentation on what solved it.
I've been able to determine that the power output of the portable device in not
sufficient to drive the headphones or the intercom music circuit. Therefore,
an in-line amplifier is required.
Some folks have suggested The Muse, but with limited success. Some folks have
offered amplfiers, but their web sites no longer have the product. A Radio Shack
part (33-1109) has also been offered but no record of whether it worked or
not. Finally, Bob offers a mini-project to build your own. That appears a bit
much for me to complete.
Okay, so how have folks solved the problem? Do the small battery operated in-line
amplifiers work? I hate to bring another battery device into the cockpit.
Are there other products out there? Does someone offer Bob's amplifier already
built?
Inquiring minds want to know.
Randy
F1 Rocket
I've been wandering around in the archives for a couple of hours searching for
resolutions to my problem of low audio output by my MP3 player into my PM3000
intercom. What's amazing is the number of people that have the problem but the
lack of documentation on what solved it.
I've been able to determine that the power output of the portable device in not
sufficient to drive the headphones or the intercom music circuit. Therefore,
an in-line amplifier is required.
Some folks have suggested The Muse, but with limited success. Some folks have offered
amplfiers, but their web sites no longer have the product. A Radio Shack
part (33-1109) has also been offered but no record of whether it worked or not.
Finally, Bob offers a mini-project to build your own. That appears a bit much
for me to complete.
Okay, so how have folks solved the problem? Do the small battery operated in-line
amplifiers work? I hate to bring another battery device into the cockpit. Are
there other products out there? Does someone offer Bob's amplifier already
built?
Inquiring minds want to know.
Randy
F1 Rocket
________________________________ Message 2 _____________________________________
From: Brian Lloyd
Subject: Re: AeroElectric-List: Low Audio Output
f1rocket(at)comcast.net wrote:
> I've been able to determine that the power output of the portable
> device in not sufficient to drive the headphones or the intercom
> music circuit. Therefore, an in-line amplifier is required.
Actually, power is not the issue. Most audio panels have a relatively high input
impedance for the music input so you really need voltage gain, not power gain.
A pair of op-amps would give enough gain to accomplish what you want.
OTOH, has anybody talked to the maker of the audio panel? This seems to be a pretty
common problem. OTOH, I have no problem with my PMA-7000 audio panels in
my airplanes. My iPod seems to have enough voltage drive to achieve a comfortable
listening level.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________ Message 3 _____________________________________
From: "Ross Mickey"
Subject: RE: AeroElectric-List: Low Audio Output
Brian,
Fortunately I had just purchased a 6000 series PS Engineering audio
panel when this whole issue of low volume levels was being discussed on
the list. The solution to the low volume issue by PS Engineering was to
design the 7000 series. Since I had not opened the box on my 6000
series, I was able to trade it in for a 7000. The main difference, in
this regard, is the 7000 series has a separate volume control for audio
inputs and the 6000 does not. Those with the 6000 series are left to
solve the problem with an add-on.
Ross Mickey
N9PT
-----Original Message-----
OTOH, has anybody talked to the maker of the audio panel? This seems to
be a pretty common problem. OTOH, I have no problem with my PMA-7000
audio panels in my airplanes. My iPod seems to have enough voltage
drive to achieve a comfortable listening level.
________________________________ Message 4 _____________________________________
From: f1rocket(at)comcast.net
Subject: Re: AeroElectric-List: Low Audio Output
>A pair of op-amps would give enough gain to accomplish what you want.
>
Sorry for being dense, but can you translate that into a product recommendation?
Thanks.
Randy
F1 Rocket
A pair of op-amps would give enough gain to accomplish what you want.
Sorry for being dense, but can you translate that into a product recommendation?
Thanks.
Randy
F1 Rocket
________________________________ Message 5 _____________________________________
From: "John Slade"
Subject: RE: AeroElectric-List: Low Audio Output
> >A pair of op-amps would give enough gain to accomplish what you want.
> >
> Sorry for being dense, but can you translate that into a product
> recommendation? Thanks.
>
> Randy
> F1 Rocket
Don't feel dense, Randy.
I've had the same problem for 3 months, and have asked the same question.
I'm following this thread hoping (this time) for a solution. Other similar
threads have lead nowhere. I don't want to build anything. I just want to
buy some simple, cheap gizmo that'll boost the audio on my plug in portable
CD player so I can actually hear it.
Regards,
John Slade
Turbo Rotary Cozy IV
________________________________ Message 6 _____________________________________
From: Brian Lloyd
Subject: Re: AeroElectric-List: Low Audio Output
f1rocket(at)comcast.net wrote:
>
>
>>A pair of op-amps would give enough gain to accomplish what you want.
>>
>
> Sorry for being dense, but can you translate that into a product recommendation?
Thanks.
Now it is my turn to be sorry. I spoke before thinking. I was thinking in terms
of building something but you are looking for an off-the-shelf solution. What
you need is a preamp. And, sorry, I can't think of any that are a) cheap,
b) small, and c) powered by 12V.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________ Message 7 _____________________________________
From: "John Slade"
Subject: RE: AeroElectric-List: Low Audio Output
> > Sorry for being dense, but can you translate that into a
> product recommendation? Thanks.
How about this little baby?
2x7W 12V Walkman Stereo Amplifier Kit $29 fully assembled.
http://www.hobbytron.net/CK154A.html?AID=10289758&PID=1117139
Would this do the job for us?
John Slade
________________________________ Message 8 _____________________________________
From: Rick Girard
Subject: Re: AeroElectric-List: Low Audio Output
I realize this isn't exactly off the shelf, but what about the
amplifiers in cheap computer speakers? Go to a PC recycler, or take the
wife garage saleing for a day and buy a pair of computer speakers for a
dollar. There is also the option of buying amplified speakers made
specifically for walk men and ipod style personal stereos, but they're
not likely to be a buck. Tear the guts out, put it in an altoid box and
double back tape it out of the way. Just a PBI.
Rick Girard
________________________________ Message 9 _____________________________________
From: "royt.or(at)netzero.com"
Subject: AeroElectric-List: RE: Low Audio Output
I've been using a Radio Shack headphone booster (pn 33-1109)and portable CD/MP3 player in my plane with Garmin 340 audio panel, Peltor 7004 headset and/or Lightspeed XL20 headset. This has been marginal but not ideal. I've purchased parts to build HeadBanger headphone amp. This is also available prebuilt. See http://www.minidisc.org/headbanger.html I plan to run this from the plane with a 12v to 9v powersupply.
I recently installed a Headsets Inc ANR kit in my Peltor. See http://www.headsetsinc.com/ The volume output of the upgraded headset is much louder. If I always flew solo, I would be very happy with the portable player, Radio Shack booster and ANR'ed Peltors. I'm still planning to build the amp and power supply. I'll power the Headsets Inc ANR from the same power supply.
I'll report back when I have completed and installed the HeadBanger amp.
(Garmin also say's there are four surface mount resistors which can be removed
to increase the external audio volume and may increase the noise. My local shop
quote to do this seemed out rageous. Something like $150.)
Regards,
Roy
N601RT: CH601HDS, nose gear, Rotax 912ULS, All electric, IFR equipped, 230hrs,
320 landings
________________________________ Message 10 ____________________________________
From: Richard Tasker
Subject: Re: AeroElectric-List: Low Audio Output
Great but not what he needs. This would be perfect if one wanted to
take the output of the MP3 player and drive some speakers, but would not
work to just amplify the voltage to feed into the PS3000.
Sorry, Dick Tasker
John Slade wrote:
>
>
>
>>>Sorry for being dense, but can you translate that into a
>>>
>>>
>>product recommendation? Thanks.
>>
>>
>How about this little baby?
> 2x7W 12V Walkman Stereo Amplifier Kit $29 fully assembled.
>
> http://www.hobbytron.net/CK154A.html?AID=10289758&PID=1117139
>
>Would this do the job for us?
>John Slade
>
>
>
>
________________________________ Message 11 ____________________________________
From: Brian Lloyd
Subject: Re: AeroElectric-List: Low Audio Output
John Slade wrote:
> How about this little baby?
> 2x7W 12V Walkman Stereo Amplifier Kit $29 fully assembled.
>
> http://www.hobbytron.net/CK154A.html?AID=10289758&PID=1117139
>
> Would this do the job for us?
Yes, it should.
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________ Message 12 ____________________________________
From: Charlie England
Subject: Re: AeroElectric-List: Low Audio Output
f1rocket(at)comcast.net wrote:
>
>I've been wandering around in the archives for a couple of hours searching for
resolutions to my problem of low audio output by my MP3 player into my PM3000
intercom. What's amazing is the number of people that have the problem but the
lack of documentation on what solved it.
>I've been able to determine that the power output of the portable device in not
sufficient to drive the headphones or the intercom music circuit. Therefore,
an in-line amplifier is required.
>Some folks have suggested The Muse, but with limited success. Some folks have
offered amplfiers, but their web sites no longer have the product. A Radio Shack
part (33-1109) has also been offered but no record of whether it worked or
not. Finally, Bob offers a mini-project to build your own. That appears a
bit much for me to complete.
>Okay, so how have folks solved the problem? Do the small battery operated in-line
amplifiers work? I hate to bring another battery device into the cockpit.
Are there other products out there? Does someone offer Bob's amplifier already
built?
>Inquiring minds want to know.
>Randy
>F1 Rocket
>
Here's the link to the RS 33-1109:
http://www.radioshack.com/images/ProductCatalog/Manuals/OME33-1109.pdf
40 mW is .8 volts into a 16 ohm load & isn't likely to do the trick. I'd
want at least 2-3 volts output to give myself a little wiggle room.
Just for grins, here are some audiophile quality headphone amps that
could be made to work, but might be a little higher quality than what
you need.
http://www.headphone.com/layout.php?topicID=3&subTopicID=27
This has more gain than you really need & still costs too much...
http://www.opamplabs.com/m9c.htm
Does the desire for plug&play arise out of the need for speed &
convenience, or 'fear of soldering'? FWIW, if you can wire your airplane
you can assemble a simple kit of electronic parts. If you just 'must
have' plug & play, I'll call our local A/V supplier tomorrow & see
what's available.
Charlie
(electronics tech in a former life)
________________________________ Message 13 ____________________________________
From: Charlie England
Subject: Re: AeroElectric-List: Low Audio Output
My experience with similar devices says it will work just fine. It's
capable of just over 4 volts output (should be plenty to drive the
intercom) into 4 ohms & it shouldn't care if it sees ~600 ohms instead
of 4 ohms. The higher impedance reduces the load on the amplifier. As
an analogy, think of your 500 amp battery supplying power to a comm.
transmitter with a 5 amp current demand.
Just start with the source output level at a midrange setting & the
amp's input controls near minimum, then bring up the amp's volume
slowwwly while playing something through the source.
Charlie
Richard Tasker wrote:
>
>Great but not what he needs. This would be perfect if one wanted to
>take the output of the MP3 player and drive some speakers, but would not
>work to just amplify the voltage to feed into the PS3000.
>
>Sorry, Dick Tasker
>
>John Slade wrote:
>
>
>
>>
>>
>>
>>
>>
>>>>Sorry for being dense, but can you translate that into a
>>>>
>>>>
>>>>
>>>>
>>>product recommendation? Thanks.
>>>
>>>
>>>
>>>
>>How about this little baby?
>> 2x7W 12V Walkman Stereo Amplifier Kit $29 fully assembled.
>>
>> http://www.hobbytron.net/CK154A.html?AID=10289758&PID=1117139
>>
>>Would this do the job for us?
>>John Slade
>>
________________________________ Message 14 ____________________________________
From: "Richard E. Tasker"
Subject: Re: AeroElectric-List: Low Audio Output
Well, you are probably right. I am an electrical engineer :-) and
look at it as not the correct device for the intended purpose - to do a
little preamplification of his MP3 player to feed to his PM3000 intercom.
While either should work (if the problem has been stated correctly) I
would suggest that this would be a more appropriate solution (from the
same source):
http://www.hobbytron.net/vk2572.html
Dick Tasker
Charlie England wrote:
>
>My experience with similar devices says it will work just fine. It's
>capable of just over 4 volts output (should be plenty to drive the
>intercom) into 4 ohms & it shouldn't care if it sees ~600 ohms instead
>of 4 ohms. The higher impedance reduces the load on the amplifier. As
>an analogy, think of your 500 amp battery supplying power to a comm.
>transmitter with a 5 amp current demand.
>
>Just start with the source output level at a midrange setting & the
>amp's input controls near minimum, then bring up the amp's volume
>slowwwly while playing something through the source.
>
>Charlie
>
________________________________ Message 15 ____________________________________
=== message truncated ===
________________________________________________________________________________
| Subject: | Re: Low Audio Output |
In a message dated 6/30/2004 9:12:47 PM Eastern Standard Time,
retasker(at)optonline.net writes:
Well, you are probably right. I am an electrical engineer :-) and
look at it as not the correct device for the intended purpose - to do a
little preamplification of his MP3 player to feed to his PM3000 intercom.
While either should work (if the problem has been stated correctly) I
would suggest that this would be a more appropriate solution (from the
same source):
http://www.hobbytron.net/vk2572.html
Dick Tasker
Dick,
I agree that this little Hobbytron amp is a much better solution. This amp
is designed for a 1k output impedance and will meet matching needs more
closely. An amp with a 4 ohm output impedance will tend to have a very sensitive
(too sensitive) of an output gain adjustment to be practical driving the high
impedance input to the intercom amp in question.
Another concern is: when mismatching impedances, fidelity goes out the
window. Aren't we striving to have the volume needed and also be able to hear
a
good clean signal above all of the other noise in the cockpit?
Perhaps I am being too picky here, but I went into the shop and hooked up my
old Craig Power Play 8 track automobile tape deck (Yes, saved from the
sixties) so that I could again hear what 50% distortion sounds like at 50 watts
rms. How did I ever listen to that trash?
Close impedance matching will solve many sins!.
John P. Marzluf
Columbus, Ohio
Kitfox Outback (out back in the garage)
________________________________________________________________________________
| From: | Brian Lloyd <brianl(at)lloyd.com> |
| Subject: | Re: Low Audio Output |
KITFOXZ(at)aol.com wrote:
> I agree that this little Hobbytron amp is a much better solution. This amp
> is designed for a 1k output impedance and will meet matching needs more
> closely. An amp with a 4 ohm output impedance will tend to have a very sensitive
> (too sensitive) of an output gain adjustment to be practical driving the high
> impedance input to the intercom amp in question.
Well ... not really. The output impedance of this little amp is actually well
under an ohm. Most of these little amps are voltage amps with very low output
impedances. Even a preamp using an op-amp is going to have a sub-10-ohm output
impedance. And even with that the output impedance is going to be a function
of the amount of feedback.
> Another concern is: when mismatching impedances, fidelity goes out the
> window.
Well ... no. It can be a problem when you have a high impedance source because
even relatively small capacitance will roll off the high frequencies but we are
dealing with very low source impedances so that is not an issue. If you look
at them closely you will find that the little power amp chip is nothing more
than an op-amp with high-output-current capability. As for audio quality, it
is not going to be that much different than a low-signal op-amp. (And if you
audiophile geeks want to contest the previous statement, fine by me. I will
concede that it doesn't sound as good and I won't give you an argument.)
> Aren't we striving to have the volume needed and also be able to hear a
> good clean signal above all of the other noise in the cockpit?
I would think so. I think you will find it will sound just fine. I doubt that
the audio stage in the audio panel is more "hi-fi" than the LM380 audio output
chip used in that cheap little audio amp.
> Perhaps I am being too picky here, but I went into the shop and hooked up my
> old Craig Power Play 8 track automobile tape deck (Yes, saved from the
> sixties) so that I could again hear what 50% distortion sounds like at 50 watts
> rms. How did I ever listen to that trash?
We didn't know better. The amps in those things were crap. They were non-linear
as hell and they had boatloads of crossover notch distortion. Engineers will
still trying to use transistors as voltage amplifiers.
Oh, and they didn't put out much power either so they were always clipping. They
ran straight off the 12V rail so they could only produce about 7W into 4 ohms
before they started to clip. Of course, they ran them hard into clipping to
get the RMS power up at some gross level of distortion like 20%. Even so the
only produced something like 12W. It wasn't until well after the 8-track that
they started using bridged output stages. That would let them swing 24V peak-to-peak
with a 12V supply thus providing about 25W into 4 ohms without clipping.
BTW, that is why so many in-dash radios are "100W" today (four bridged
amps producing 25W each).
> Close impedance matching will solve many sins!.
Well ... not really. Rarely do we match impedances in audio systems (I mention
the exception below). Normally we use low output impedance driving a high input
impedance. The output voltage will be sufficient to meet the input voltage
requirements of the next stage and the next stage's input impedance is high
enough to not be a significant load on the previous stage.
The only time we match impedances in audio anymore is in vacuum-tube output stages
in order to get maximum power transfer. Solid-state amps they are very low
impedance with some maximum voltage swing and some maximum current capability.
The latter determines how low a load impedance the amp can drive.
And for you audiophile geeks out there, yes, I am fully aware of current-mode cabling
systems (high output impedance into a low input impedance). They don't
really apply here but I will be glad to talk about them outside this forum.
> John P. Marzluf
> Columbus, Ohio
> Kitfox Outback (out back in the garage)
>
>
>
>
>
>
--
Brian Lloyd 6501 Red Hook Plaza
brianl(at)lloyd.com Suite 201
http://www.lloyd.com St. Thomas, VI 00802
+1.340.998.9447 (voice) +1.360.838.9669 (fax)
There is a time to laud one's country and a time to protest.
A good citizen is prepared to do either as the need arises.
________________________________________________________________________________
| From: | Charlie England <ceengland(at)bellsouth.net> |
| Subject: | Re: Low Audio Output(now not so low) |
f1rocket(at)comcast.net wrote:
>
>Thanks for all the great responses. I really appreciate your willingness to share
your knowledge with all of us.
>With the options that have been presented, there doesn't appear to be one that
is plug-n-play. Also, all of the options presented include a battery as the
power source to the amp. I had hoped to avoid that as well.
>I believe there is a maketing opportunity out there for a box with two stereo
jacks and a power lead to 12V. Again, I can't believe that someone hasn't come
up with a solution somewhere that they would be willing to sell. If there is
anyone out there willing to put one of these together, please contact me off-line
at f1rocket(at)comcast.net. At this point in my project, I have more $$ than
time.
>If that doesn't pan out, I'll probably buy an assembled card and take a stab at
putting something together. Again, my thanks to all who contributed to this
thread.
>Randy
>F1 Rocket
>
>
>Thanks for all the great responses. I really appreciate your willingness to share
your knowledge with all of us.
>
>
>With the options that have been presented,there doesn't appear to be one that
is plug-n-play.Also, all of the options presented include a battery as the power
source to the amp. I had hoped to avoid that as well.
>
>
>I believe there is a maketing opportunity out there for abox with two stereo jacks
and a power lead to 12V. Again, I can't believe that someone hasn't come
up with a solution somewhere that they would be willing to sell. If there is anyone
out there willing to put one of these together, please contact me off-line
at f1rocket(at)comcast.net. At this point inmy project, I have more $$ than time.
>
>
>If that doesn't pan out, I'll probably buy an assembled card andtake a stab at
putting something together. Again, my thanks to all who contributed to this thread.
>
>
>Randy
>
>
>F1 Rocket
>
Ok, here ya go:
http://www.directproaudio.com/product.cfm?directid=53503
http://www.directproaudio.com/product.cfm?directid=30370
data sheet:
http://www.directproaudio.com/images/products/ha43man.pdf
http://www.directproaudio.com/product.cfm?directid=53829
data sheet for above:
http://www.directproaudio.com/images/products/headamp.pdf
The 2nd one is the most likely candidate. 1/4" stereo phone jacks in &
out, 20 dB gain, 12 V DC power jack.
(No, you won't be using it in its design environment. Do you care? :-) )
Charlie
(I can't believe it took me this long to find this)
________________________________________________________________________________
June 18, 2004 - July 01, 2004
AeroElectric-Archive.digest.vol-dh