AeroElectric-Archive.digest.vol-ca
May 13, 2003 - May 26, 2003
>
>Sounds like a dead short.
>It would pull down the voltage and the excess amperage would trip the
>breaker.
I agree . . . check to make sure your diode on
the b-lead contactor isn't hooked up backwards
or shorted.
>Cy Galley, TC - Chair, Emergency Aircraft Repair, Oshkosh
>
>Editor, EAA Safety Programs
>cgalley(at)qcbc.org or experimenter(at)eaa.org
>
>Always looking for articles for the Experimenter
Cy, Have you picked through the stuff on downloadables
section of aeroelectric.com? If there's something you
like there, let me know . . . it might need updating.
Bob . . .
________________________________________________________________________________
| From: | "John Karnes" <jpkarnes(at)charter.net> |
| Subject: | Re: OV circuit breaker tripping |
> >Sounds like a dead short.
> >It would pull down the voltage and the excess amperage would trip the
> >breaker.
>
> I agree . . . check to make sure your diode on
> the b-lead contactor isn't hooked up backwards
> or shorted.
How do I check to see if the diode is shorted? I know it's not backwards as
I haven't changed it and it was working fine before. Could the high heat in
the engine compartment have caused this? (I'm talking HIGH heat!)
John Karnes
________________________________________________________________________________
| From: | "Rick Fogerson" <rickf(at)cableone.net> |
| Subject: | Fw: Electric Bob - Microair Radio-Xpdr Wire Harness |
----- Original Message -----
From: Rick Fogerson
Subject: Microair Radio-Xpdr Wire Harness
Hi Bob,
Are you going to be selling wiring harness's for the Microair radio or xpdr anytime
soon?
Rick Fogerson
________________________________________________________________________________
| From: | Geoff Evans <hellothaimassage(at)yahoo.com> |
| Subject: | Dual electronic ignition - revisited again |
Hi Bob.
I thought I was all squared away after our message exchange of a few months
ago, but some recent postings of yours on the list have rekindled my
confusion.
Our prior conversations were about using the Z-13 architecture for dual
electronic ignitions, and whether the Z-13 system was any more likely to
result in an electrically-caused engine failure (with dual electronic
ignitions) than a something like a Z-11 system with an aux battery. At the
time, I was confused by some prior postings and some seemingly conflicting
language in your book.
Basically, my question was this: For an engine with dual electronic
ignitions, would I be better off with two batteries and one alternator, or
one battery and two alternators (removing all other variables, and assuming
the batteries are well-maintained)?
You said the following (among other things):
Depends on what you choose to worry about. A PROPERLY MAINTAINED
RG battery is the single most reliable power source you can put
in your airplane. Could you run dual electronic ignition systems
from their own fuses on a single battery bus? Sure.
Now, what about alternator-out operations. With one alternator
and a DESIGN REQUIREMENT that you can exhaust fuel before your
battery(ies) run down may suggest some variations on the theme.
An AUX battery more than a year old and less than two years
old running ONE ignition system says that in the extreme case
of running the main battery flat with e-bus loads, the engine
keeps running. Alternatively, if you're in a position to
get shed of vacuum operated accessories and the pump that
drives them, then a second alternator on the vacated vacuum
pump pad is a no-brainer decision.
Given that (the "no-brainer decision" comment), I was all ready to stick with
the Z-13 architecture for a dual electronic ignition engine.
Then I read a post of yours last Sunday where you said (in reply to someone
else):
> >
> > I was just amused at your statement on Z-13 because I thought that you
> > did not advocate this setup for dual electronic ignition?
Correct. Sometimes after a day of brain-wrestling with
these things all day at RAC, my thought train gets
derailed . . .
So, I guess what I'm looking for is some kind of statement akin to one of the
following:
"We at Aeroelectric Connection do not advocate using the Z-13 architecture
for an aircraft with dual electronic ignitions. We prefer dual batteries
instead."
or...
"We at the Aeroelectric Connection believe that the Z-13 architecture does
not have any greater chance of total electrical failure than a Z-11 system
with an aux battery. In fact, we think it's a better option, and it's
perfectly viable for use with dual electronic ignitions."
If you'd rather not make either of those statements (for liability reasons,
or whatever), I totally understand. I'm just trying to get a feel for your
opinion on the matter. Would you personally have any problem getting in an
airplane that uses the Z-13 architecture with dual electronic ignitions?
I'm trying to avoid the added weight of two full-size batteries, and I really
like the idea of having the SD-8 as a backup alternator instead. I'm also
trying to avoid the complexity of having a backup battery just for half of a
dual ignition system -- if that's even a logical position to take.
Can you put an end to the ambiguity (read: my confusion) one and for all?
Thanks much!
-Geoff
RV-8
__________________________________
http://search.yahoo.com
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: OV circuit breaker tripping |
>
> > >Sounds like a dead short.
> > >It would pull down the voltage and the excess amperage would trip the
> > >breaker.
> >
> > I agree . . . check to make sure your diode on
> > the b-lead contactor isn't hooked up backwards
> > or shorted.
>
>How do I check to see if the diode is shorted? I know it's not backwards as
>I haven't changed it and it was working fine before.
Use your ohmmeter to check the resistance across the diode.
If it (or something else on the line is shorted) it will
read very low (less than 1 ohm) no matter which way you
attach the leads.
> Could the high heat in
>the engine compartment have caused this? (I'm talking HIGH heat!)
Not likely.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Fw: Electric Bob - Microair Radio-Xpdr |
Wire Harness
>
>
>----- Original Message -----
>From: Rick Fogerson
>To: aeroelectric-list(at)matronics.com
>Subject: Microair Radio-Xpdr Wire Harness
>
>
>Hi Bob,
>Are you going to be selling wiring harness's for the Microair radio or
>xpdr anytime soon?
>Rick Fogerson
Yes, I need to make some up tomorrow morning. Which ones do you
want?
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: AutoPilot Disconnect Brain |
Teaser-05/12/03
>
>
>"Robert L. Nuckolls, III" wrote:
>
>
> >
> >
> > >2,000,000 square inches (.318845 acres)
> >
> > ??????
>
>This would be the answer when you are trying to demonstrate your stupidity
>by leaving out half the
>formula in the rush to get to the dinner table after being called three
>times, then not even
>bothering with a reasonability check before pushing the send button.
>(feeling a little silly)
Understand . . . I try to limit my silly episodes to one per day.
Bob . . .
________________________________________________________________________________
| From: | "M.J. Gregory" <m.j.gregory(at)talk21.com> |
| Subject: | Re: AutoPilot Disconnect Brain Teaser - 05/12/03 |
Bob
I was waiting for you to shake the cube and let all those one billion balls
settle so that you could add some more. I understand that stacking balls
pyramid-style can fill some 74 percent of the volume. This compares with
the 52.3 percent you have by stacking them in one-million-ball layers. The
ratio of these figures is approximately sq root 2, but I don't know if this
is the mathematically precise relationship.
I therefore calculate that you should be able to get some 1,410,000,000
balls into your cube, increasing their surface area to 4,430 sq in.
While there would be only a very little direct see-through area round the
sides with this arrangement, I shall leave it to others to calculate the
reduction in cross sectional area for your liquid flowing through from one
face to another. I suspect it would again be a factor of approximately sq
root 2.
Happy calculations.
Mike
m.j.gregory(at)cranfield.ac.uk
>
>
> > Take an array of steel balls 0.001" in diameter
> > and stack them into 1 cubic inch of volume. How
> > many balls does it take to fill the cube? What
> > is the total surface area of all balls contained
> > in the cube? What is the open (see-through) area
> > of the space between the balls for any liquid
> > that passes into one face and out the opposite face?
> >
> > Bob . . .
> >
>You'll need 1,000
3 steel balls or...
>
>1,000,000,000 balls
>
>The surface area of a sphere is... 4*pi*r
2
>
>So the area of one ball... 3.141592E-6 sq in
>So the area of a billion balls... 3,141.5 sq in or 21.8166 sq ft
>which is about 2/3 the area of a piece of plywood.
That's the part that really surprises folks . . . that
a 1" cube could have that much surface area contained
within.
>Now for the second part the wetted area...
>
>It would be 1 sq in - the area of a million circles...
>
>area of a circle = pi * r
2
>
>Area of a 0.001" diameter circle = 7.85398E-7 sq in
>Area of a million of them would be... 0.785398 sq in
>so the see through area would be... 0.214602 sq in
yup . . .
>Of course this all assumes that we stack the balls in a rectangular pattern
>1,000 balls to an edge, and the 1 cubic inch volume is a 1" x 1" x 1" cube,
>if it is anything more sinister than that then I don't have time to look it
>up. :-)
yeah, getting all those balls to set in there un-nested
takes some REAL patience.
Bob . . .
________________________________________________________________________________
| From: | <danobrien(at)cox.net> |
Slightly off topic, but if analogies exist for noise in aircraft, perhaps the answer
will be instructive nonetheless. I am finishing a new room in my house
where I want to run a cable connection for a cable modem. The preferred route
runs the cable wire along a 240 volt circuit for an air conditioner/heat pump
unit. Is there any issue with the 240 volt wire creating interference in the
cable line?
Thanks,
Dan
________________________________________________________________________________
| From: | "Cy Galley" <cgalley(at)qcbc.org> |
| Subject: | Re: OV circuit breaker tripping |
How about high temps melting or softening some wire insulation so it the
wire is rubbing some metal. I would check down stream from the CB with an
ohm meter.
Cy Galley - Bellanca Champion Club
Newsletter Editor & EAA TC
www.bellanca-championclub.com
Actively supporting Aeroncas
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: OV circuit breaker tripping
>
> >
> > > >Sounds like a dead short.
> > > >It would pull down the voltage and the excess amperage would trip the
> > > >breaker.
> > >
> > > I agree . . . check to make sure your diode on
> > > the b-lead contactor isn't hooked up backwards
> > > or shorted.
> >
> >How do I check to see if the diode is shorted? I know it's not backwards
as
> >I haven't changed it and it was working fine before.
>
> Use your ohmmeter to check the resistance across the diode.
> If it (or something else on the line is shorted) it will
> read very low (less than 1 ohm) no matter which way you
> attach the leads.
>
> > Could the high heat in
> >the engine compartment have caused this? (I'm talking HIGH heat!)
>
> Not likely.
>
> Bob . . .
>
> --------------------------------------------
> ( Knowing about a thing is different than )
> ( understanding it. One can know a lot )
> ( and still understand nothing. )
> ( C.F. Kettering )
> --------------------------------------------
>
>
________________________________________________________________________________
| Subject: | Re: Dual electronic ignition - revisited again |
| From: | John Schroeder <jschroeder(at)perigee.net> |
Geoff -
IMHO, look at the Z-14 with two 17 AH batteries. No question as to
suitability for dual electronic ignition systems.
> I'm trying to avoid the added weight of two full-size batteries, and I
> really
> like the idea of having the SD-8 as a backup alternator instead. I'm also
> trying to avoid the complexity of having a backup battery just for half
> of a
> dual ignition system -- if that's even a logical position to take.
>
> Can you put an end to the ambiguity (read: my confusion) one and for all?
>
> Thanks much!
> -Geoff
>
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
| Subject: | non-Microprocessor based Fuel Gauge Linearizer |
There has been some discussion of this, and I have not gotten very far on my plans
to build one. Since I have no shortage of stuff to make (Hey Bob, Re: Other
Life, just use you wife's washing machine for the 30G centrifuge. The spin cycle
should do 30Gs and you won't hit anybody when the thing comes apart. Paint
it gray, stick a NASA label over the Kenmore label, and you're all set! Total
cost--Old Washer, Paint, Logo....let's see.).
Here's the non-microprocessor plan for the linearizer: (As they say in school,
the exercise is left up to the reader).
1) Know the true final volume of the tank.
1) Assume the graph of Fuel Volume (Y) and Fuel Gauge Reading (x) is everywhere
a negative slope. (Not necessarily true in all cases, but then it's hopeless.)
Draw yourself a sample graph. It looks like a downhill ski run. Remember--all
negative slopes!
2) Let's assume that a four-segment straight-line approximation is adequate for
the job, divide up the X-axis into four parts and using the intersections of
the divisions with the downhill ski run, connect the dots to make four line segments.
3)---A small pause here---The purpose of the four line segments is to model the
ski-run curve of declining fuel volume versus fuel gauge reading (note that the
linearity of the sender AND the panel meter can be included as one variable).
The SLOPE (deltaX/deltaY) of these segments is going to be the voltage amplification
of four teeny little op amps that will read these parts of the curve.
It is useful to note that the way the x-axis is divided up should reflect the
geometry of the tank and the linearity of the gauge and sender. That is, in
a smoothly arcing curve, maybe simply quartering the x-axis is fine, but when
the reading error is mostly in one place, the line segments that model it should
be concentrated there. This make the job simpler, but you can make this basic
technique as complicated as you want.
4) Now having the four teeny little op amps (Quad Op Amp LM324), you add four teeny
little adjustment pots to set the slopes (gains), and a quad comparator LM339
to tell the output which one of the Op Amps is valid. There are some other
parts in this mix---
--An I-V converter chip for the input and a V-I converter chip for the output.
Is there a way to avoid this?
--A good averaging anti-slosh filter on the input. Easy...
--Low fuel setpoint alarm?
Now if someone wants to work on this. The total BOM should be less than $20. The
entire assembly in surface mount will be 1" X 1.5" X 3/8", it will weight <1
ounce, it will operate up to 30 VDC.
Here's my offer: If someone wants to build this on a proto board, design the schematic,
and do some work on it--I will build her two samples of the real thing
in surface mount. The reality of the internet is that we can design things with
world-wide brains and resources in a cooperative venture. Let's get together
on this!
Regards,
Eric M. Jones
"When dealing with the enemy, it helps if he thinks you're a little bit crazy."
--Gen. Curtis LeMay
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
| Subject: | Re: AutoPilot Disconnect Brain Teaser - |
The packing fraction for face-centered cubic packing is rho0.7405. Adjust results
accordingly.
Eric
________________________________________________________________________________
| From: | "Ian Scott" <jabiru22(at)yahoo.com.au> |
| Subject: | Cheap blind encoder. |
HI All,
I a getting a Micro air transponder, and was wondering what I should do
for encoder and antenna, in a glass plane
Ian
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>Slightly off topic, but if analogies exist for noise in aircraft, perhaps
>the answer will be instructive nonetheless. I am finishing a new room in
>my house where I want to run a cable connection for a cable modem. The
>preferred route runs the cable wire along a 240 volt circuit for an air
>conditioner/heat pump unit. Is there any issue with the 240 volt wire
>creating interference in the cable line?
>
>Thanks,
>Dan
No, "noises" from the power wiring in a house are relatively low
frequency (60 hz and harmonics plus noises generated by appliances)
while your cable modem works at hundreds of megahertz inbound traffic
and tens of megahertz outbound. Further, house wiring is carried
on parallel pairs . . . for every electron going one way there is
a companion headed the other way in close proximity . . . net result
is that magnetic fields (strongest noise coupling mode) cancel
each other.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: non-Microprocessor based Fuel Gauge |
Linearizer
>
>There has been some discussion of this, and I have not gotten very far on
>my plans to build one. Since I have no shortage of stuff to make (Hey Bob,
>Re: Other Life, just use you wife's washing machine for the 30G
>centrifuge. The spin cycle should do 30Gs and you won't hit anybody when
>the thing comes apart. Paint it gray, stick a NASA label over the Kenmore
>label, and you're all set! Total cost--Old Washer, Paint, Logo....let's see.).
>
>Here's the non-microprocessor plan for the linearizer: (As they say in
>school, the exercise is left up to the reader).
>1) Know the true final volume of the tank.
>1) Assume the graph of Fuel Volume (Y) and Fuel Gauge Reading (x) is
>everywhere a negative slope. (Not necessarily true in all cases, but then
>it's hopeless.) Draw yourself a sample graph. It looks like a downhill ski
>run. Remember--all negative slopes!
>2) Let's assume that a four-segment straight-line approximation is
>adequate for the job, divide up the X-axis into four parts and using the
>intersections of the divisions with the downhill ski run, connect the dots
>to make four line segments.
>3)---A small pause here---The purpose of the four line segments is to
>model the ski-run curve of declining fuel volume versus fuel gauge reading
>(note that the linearity of the sender AND the panel meter can be included
>as one variable). The SLOPE (deltaX/deltaY) of these segments is going to
>be the voltage amplification of four teeny little op amps that will read
>these parts of the curve. It is useful to note that the way the x-axis is
>divided up should reflect the geometry of the tank and the linearity of
>the gauge and sender. That is, in a smoothly arcing curve, maybe simply
>quartering the x-axis is fine, but when the reading error is mostly in one
>place, the line segments that model it should be concentrated there. This
>make the job simpler, but you can make this basic technique as complicated
>as you want.
>4) Now having the four teeny little op amps (Quad Op Amp LM324), you add
>four teeny little adjustment pots to set the slopes (gains), and a quad
>comparator LM339 to tell the output which one of the Op Amps is valid.
>There are some other parts in this mix---
>--An I-V converter chip for the input and a V-I converter chip for the
>output. Is there a way to avoid this?
>--A good averaging anti-slosh filter on the input. Easy...
>--Low fuel setpoint alarm?
>
>Now if someone wants to work on this. The total BOM should be less than
>$20. The entire assembly in surface mount will be 1" X 1.5" X 3/8", it
>will weight <1 ounce, it will operate up to 30 VDC.
>
>Here's my offer: If someone wants to build this on a proto board, design
>the schematic, and do some work on it--I will build her two samples of the
>real thing in surface mount. The reality of the internet is that we can
>design things with world-wide brains and resources in a cooperative
>venture. Let's get together on this!
I've built multi-slope analog systems like this. Did
a feel-spring actuator controller for some model of a Cessna
way back when that needed to adjust compression on a spring
cartridge based on IAS and a second order transfer function.
I think we did it with three op amps (two breaks in the curve).
That was the best we COULD do then, can't recommend it today.
There are microcontrollers for under $5 with built in D/A
and enough memory to hold program and scratch pad for
this kind of task. The HARDest part is building a user
i/o interface so that the end user can plug in a laptop
and adjust the lookup table to fit his airplane.
If there are enough folks really interested in this,
I have some byte-wienies out at RAC that could make this
play in software. The board layouts are rudimentary.
Bob . . .
>Regards,
>Eric M. Jones
>
>"When dealing with the enemy, it helps if he thinks you're a little bit
>crazy."
>--Gen. Curtis LeMay
>
>
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: AutoPilot Disconnect Brain Teaser - |
>
>The packing fraction for face-centered cubic packing is rho0.7405. Adjust
>results accordingly.
>
>Eric
You threw me a new one there Eric. Care to describe "packing fraction"
in 25 words or less? ;-)
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "William Yamokoski" <yamokosk(at)lmc.cc.mi.us> |
| Subject: | Radio Noise Redux |
Hi Folks,
I've made a bit of progress on the noises I was hearing in my headsets. My
main problem continues to be on the transmission side...sometimes fine, sometimes
unintelligable. The intermittent nature of the beast is the most frustrating
part. I've never been able to hear what people are reporting, but i think
I've been able to duplicate what they tell me they hear.
The MicroAir is powered from the essential bus, which in turn gets its power
from the main bus via a diode as per Bob's drawings. With engine off, main
contactors on, pushing the PTT results in a normal feedback in the headsets.
When I start adding to the current load (e.g., Naviad, GPS, transponder) things
get a little dicey. I start hearing terrible noises in the headset, but only
very intermittently. When I then turn on one of the big current loads
like the pitot heat or strobes, pushing the PTT switch switch gives me continuous
loud growling sounds....voice can barely be made out. At this point the
Grand Rapids EIS is showing 11.9 v or thereabouts.
This at least seems logical. The radio doesn't get enough electrons, I guess,
to tranmit properly. The problem is, why might this be happening with the
engine on in flight? Yesterday in flight someone reported my transmission
as unreadble, with loud background noise. At that time the EIS read 14.5 v.
Twenty minutes earlier I got a report that my transmission was clear, with a
small amount of background static.
Could there be a problem with the diode? I'm not sure if they fail in an all-or-nothing
way or if you can see a "partial." failure. I've used Bob's idea
of hooking two 6 volt batteries together to power the radio separately from
the busses. That helped me in isolating some of the the odd noises I was getting
in the headset. However, I've never used those batteries to power the
radio in flight. It seems like it would be easy enough to test-out this diode
theory...just by-pass the thing and power the essential bus with a simple wire
from the main bus for a while. But am I barking up the wrong tree here?
Another Glastar/Subaru owner has replaced his diode due to a failure. Any
thoughts appreciated.
Thanks
Bill Yamokoski
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
Noise Redux]
----- Original Message -----
From: "William Yamokoski" <yamokosk(at)lmc.cc.mi.us>
Subject: AeroElectric-List: Radio Noise Redux
>
> Hi Folks,
The MicroAir is powered from the essential bus, which in turn gets
its power from the main bus via a diode as per Bob's drawings.
> Could there be a problem with the diode? I'm not sure if they fail in
an all-or-nothing way or if you can see a "partial." failure It seems
like it would be easy enough to test-out this diode theory...just by-pass
the thing and power the essential bus with a simple wire from the main bus
for a while. But am I barking up the wrong tree here? Another
Glastar/Subaru owner has replaced his diode due to a failure. Any thoughts
appreciated.
> Thanks
> Bill Yamokoski
Diodes. . . . . I get a little excited when I hear stories of diodes
failing.
I've quoted the relevant parts above.
Now, my anecdote, prior to asking a ques: Anecdote: While Avionics Officer
for an A-7D unit, one of the Big Eight test stations (each of the eight
costing about $1 million each) suffered a diode "short" on a circuit card.
This simple 2 cent piece failed - resulting in high current flow in that
circuit, which was not protected - designers didn't consider the diode
failure mechanism. Well, the high current cascaded throughout the test
station and resulted in something like a lightning strike on the entire test
station. We spent months and LOTS of unit funds repairing that test
station.
Now, I'm in the role of home builder-designer of my RV-6 electrical system.
And we've been talking many months about an Endurance Bus, with a diode
allowing power to flow to the E-bus from the main bus, and to prevent
battery drain from the E-bus to the main bus when main bus is shut down for
alternator failure.
A diode.
I'll bet those who work in this field have other stories about diode
failures.
Are there some diodes that are better (more durable, longer lasting) than
other diodes?
What level of "diode spec" ought to be sufficient to avoid "typical" diode
failures? Is "bigger" better?
What are diodes most sensitive to? (that would cause them to fail)
If I can't "rely" on the diode between Main & E busses, then I might
consider "adding parts count" to detect failure of this critter; or special
pilot operating procedures to use voltmeter wired to specific, switch
selectable places, with opening and closing of e-bus switch or other means
of verifying, on every flight, that the diode is function correctly. (Do I
smell my own paranoia oozing out?)
David Carter
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Dual electronic ignition - revisited |
again
>
>
>Hi Bob.
>
>I thought I was all squared away after our message exchange of a few months
>ago, but some recent postings of yours on the list have rekindled my
>confusion.
>
>Our prior conversations were about using the Z-13 architecture for dual
>electronic ignitions, and whether the Z-13 system was any more likely to
>result in an electrically-caused engine failure (with dual electronic
>ignitions) than a something like a Z-11 system with an aux battery. At the
>time, I was confused by some prior postings and some seemingly conflicting
>language in your book.
>
>"We at Aeroelectric Connection do not advocate using the Z-13 architecture
>for an aircraft with dual electronic ignitions. We prefer dual batteries
>instead."
>
>or...
>
>"We at the Aeroelectric Connection believe that the Z-13 architecture does
>not have any greater chance of total electrical failure than a Z-11 system
>with an aux battery. In fact, we think it's a better option, and it's
>perfectly viable for use with dual electronic ignitions."
Let's review some simple-ideas which you need to
ponder to answer the question for yourself:
(1) If a system has but one battery and no alternators
proven to be stand-alone providers of electrical energy
then there IS risk of loosing the whole system should the
one battery become unavailable.
(2) If you have an electrically dependent engine with stand-alone
backups (like dual ignition) then to preserve as much of the
independent qualities of the dual systems, then two power
sources capable of operation independent of each other are
indicated.
(3) If one of those power sources cannot be an alternator, the
two batteries are indicated.
(4) Obviously, if one of the batteries is tasked only with
supporting one ignition system, then it's capacity could
be sized to some value that supports ignition for duration
of fuel aboard.
(5) If a second, small battery is part of your planning,
it need not be tied to the system with a heavy contactor.
The original Aux Battery Management Module article spoke
of an "Ignition" Battery Management Module and suggested
a hefty power relay making connection with the main bus
to keep a small battery charged. This relay was NOT closed
during cranking to assist the main battery in getting the
engine started.
(6) If the light weight and low cost of the SD-8 as a
second engine drive power source is attractive to you
then there's no reason why you couldn't take advantage of
it using Figure Z-13 but it has little relevance to the
reliability considerations for the dual electronic ignitions.
It would be handy if it worked when the main alternator
quits but it's not NECESSARY for comfortable completion
of flight and would assure power to at least one
ignition in the face of multiple failures (very
unlikely).
(7) You might consider a Z-13 system with the aux battery
connected so as to parallel with the main battery for
normal ops and battery charging. If the aux battery management
module is attractive to you, I might drive it from the
e-bus so that during main alternator out operations,
it would allow the second battery to stay connected to
the main battery only if the SD-8 were working and
not overloaded because too much stuff is turned on.
(8) Now, likelihood of finding yourself without enough
engine driven power to keep necessary goodies running
is on same order as wing or propeller falling off.
Even if you loose the battery contactor or wiring
to the main battery, you've still got a small battery
that would stabilize the SD-8 for unlimited endurance
operations from the e-bus.
Now, sort through these ideas and see if you have any
disagreement or question as to their validity. Once
the suite of ideas is validated, do you see a way to
assemble them into a solution suited to your needs?
>If you'd rather not make either of those statements (for liability reasons,
>or whatever), I totally understand. I'm just trying to get a feel for your
>opinion on the matter. Would you personally have any problem getting in an
>airplane that uses the Z-13 architecture with dual electronic ignitions?
Liability? Let's not make this a decision based on anyone's
opinion but your own. The whole universe runs on physics and
each basic fact of physics is stone simple . . . a simple-idea.
The task is for you to sort through a basket of simple-ideas
and make a considered decision based on your own understanding . . .
not upon anyone else's opinion.
>I'm trying to avoid the added weight of two full-size batteries, and I really
>like the idea of having the SD-8 as a backup alternator instead. I'm also
>trying to avoid the complexity of having a backup battery just for half of a
>dual ignition system -- if that's even a logical position to take.
>
>Can you put an end to the ambiguity (read: my confusion) one and for all?
I can't "put an end" to it, that's not part of my magic wand's
bag of tricks. I can put out some simple-ideas for you or
anyone else to critique, correct or amplify so that
you and others can gather them into a system that
offers the comfort of understanding and the utility
of system reliability.
So, given what's been outlined above, I encourage further
discussion to see if those things can satisfy your
needs. This is the first time I've considered the
architecture described in (7) . . . does anyone have
something to contribute there?
Bob . . .
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
| Subject: | Re: 100 % Solution (diode-fed supportbatt-was Avionics |
bus)
What Bob says about Mallory (and other) supercaps seems to be true. I looked at
putting some supercaps near the starter, but the technology has fallen out of
favor for the reasons Bob mentions. For situation where the rate of charging
or discharging is important, they still have some use.
I do wonder--In a power-limited situation, would it make sense to have greater
energy available for the first couple seconds of radio transmission or reception?
Would the availability of 15 Volts in the first second extend the low voltage
operation? I think this seems reasonable.
For anyone interested in battery power, the advances in Lithium-Ion makes the use
of anything else questionable, especially if you don't need to fly for a while.
Batteries are heavy and Lithium-Ion is CERTAINLY going to supplant everything
else, even the much vaunted micro-fuelcells have fallen behind the curve.
Li-Ion advantages--
Li-Ion cells weigh around half that of a NiCd or NiMH cell of the same capacity.
In addition Li-Ion cells are 40 to 50% volumetrically smaller than NiCd cells,
and 20-30% smaller than NiMH cells.The average voltage of a Li-Ion cell (3.6-3.7V)
is equivalent to three NiCd or NiMH cells (each 1.2V). Li-Ion cells can
typically be discharged at rates up to 1.5C continuous. Very safe environmentally.
No Lithium metal, other electrode is carbon. Shapes....any shape and flexible
too. When fully charged and fully discharged under normal conditions, the
life of a Li-Ion cell is between 300 and 500 cycles (RG batteries are half
this). No "memory effect" Fast charge capable, wide operating temperature range,
enormous charge retentions, trickle charging is rarely needed. Many batteries
are "smart"; that is--they have a computer doing tricks inside of it.
Regards
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones(at)charter.net
________________________________________________________________________________
| From: | PTACKABURY(at)aol.com |
Bob et al: First background one: I built a LongEZ some 20 years ago and
have learned to live with some quirks with the electrical system. For
example when I transmit the fuel low lites come on and the Navaid autopilot
rolls into a 30 degree bank. I gave up trying to find these uninvited bugs
and have learned to enjoy them as part of life's little surprises.
Background two: a friend has just completed a beautiful Lancair IVP with a
very professional wiring job. When he transmits his SFS fuel indicators go
to zero (while using the bottom, externally mounted antenna, not when using
the antenna mounted inside the tail). He has been trouble shooting for a few
weeks but so far no luck. Now to the point: I am just about ready to string
wires and add an external com antenna to my Lancair IV and would like to
avoid repeating these interference problems (EMI??). Advice? Does and
don'ts? Are these quirks just part of life with a plastic airplane? Are
they the result of multiple grounds, insufficient wire shielding, bad antenna
installation, com coax too close to other wires, or too few chicken bones
tossed during the build process? all help is appreciated--paul
________________________________________________________________________________
| From: | "Jim Pack" <jpack(at)igs3.com> |
| Subject: | Re: Dual electronic ignition - revisited again |
With all the talk of a 20 am standby alt & a second battery, why not z14
(dual alt, dual bat)? If it were my plane with dual EI's, I'd want to make
sure that at least one was always running (no single point failures in the
electrical system will stop the engine).
- jim
> . . . does anyone have
> something to contribute there?
>
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | SD-8 Alternator Questions |
This recent discussion on dual batteries vs. dual alternators had me
thinking about the system that I am planning. I'll be using the "All
Electric on a Budget" except with an internally regulated alternator (with
OVM and another big contactor), but my question is about the SD-8. I have
assumed that the SD-8 is a true permanent magent alternator which means that
if you spin it, it will make juice. Is this true?
I have heard bits and pieces of debate on this list about the SD-8 requiring
power to get started but then the battery can go away after the unit is
running and assuming a good filter it will produce decent power. I assume
that these concerns are due to the fact that the relay will need some
external source of power to get it closed, but once it is closed there is no
further need of the battery. I guess I am challenging my own assumptions
and want to understand this little alternator a little better.
I also read here once that it was not a good idea to start this little
alternator during the pre-flight checks because then it will sit there and
make power the whole flight and that this was somehow bad for it. I would
really like to be able to check this little guy during the pre-taxi check
list and would like to better understand what is going on inside it before I
plunk down the money.
Although my engine will not totaly rely on electrical power my panel does.
I'll be blind as the proverbial bat if I lose my electrical system.
Oh BTW what was the answer to the water molecule ping pong ball question? I
would guess they would be a few inches deep, but I barely passed Chemistry
so I can't remember all that mole stuff.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Dual electronic ignition - revisited |
again
>
>With all the talk of a 20 am standby alt & a second battery, why not z14
>(dual alt, dual bat)? If it were my plane with dual EI's, I'd want to make
>sure that at least one was always running (no single point failures in the
>electrical system will stop the engine).
>
>- jim
I think he was talking about the 4# SD-8 as a standby and
further interested in downsizing the #2 battery to serve
the need of a #2 ignition and then only if BOTH alternators
have failed.
With two engine driven power sources, the need for e-bus
capacity in the main battery goes away. If one can find
low capacity batteries with the ability to dump starting
current, a Z-13 configured as I described has tremendous
potential for weight and volume savings. The biggest
gotcha is cost of low capacity batteries that will
also crank . . . but again, you can run this battery
until it croaks if you have two engine driven power sources.
Bob . . .
________________________________________________________________________________
| From: | Geoff Evans <hellothaimassage(at)yahoo.com> |
| Subject: | Re: Dual electronic ignition - revisited again |
Bob. Thank you so much for that elegant and concise response. It definitely
adds some perspective.
Bob wrote:
(7) You might consider a Z-13 system with the aux battery
connected so as to parallel with the main battery for
normal ops and battery charging. If the aux battery management
module is attractive to you, I might drive it from the
e-bus so that during main alternator out operations,
it would allow the second battery to stay connected to
the main battery only if the SD-8 were working and
not overloaded because too much stuff is turned on.
So, given what's been outlined above, I encourage further
discussion to see if those things can satisfy your
needs. This is the first time I've considered the
architecture described in (7) . . . does anyone have
something to contribute there?
That was going to be my next question... In regard to (7) above, would the
small aux battery actually need to be "driven" from the e-bus, or could it be
connected to the main battery side of the main battery contactor where the
the SD-8 hooks up? It seems to me that if we connected it here, in the
unlikely event that the aux battery was deeply discharged, it would prevent
high charging currents flowing through the main battery bus and the e-bus.
Also, would you recommed the hefty power relay to connect the small aux
battery in lieu of the shottky diode that is shown on the drawings that come
with the Lighspeed ignition? Personally, I don't know anything about shottky
diodes, so I guess this question is more of a request for a "compare and
contrast" between a relay connection method and a shottky diode connection
method.
Thanks again!
-Geoff
__________________________________
http://search.yahoo.com
________________________________________________________________________________
| From: | Jerzy Krasinski <krasinski(at)direcway.com> |
| Subject: | Re: non-Microprocessor based Fuel Gauge Linearizer |
Eric M. Jones wrote:
>.....Now having the four teeny little op amps (Quad Op Amp LM324), you add four
teeny little adjustment pots to set the slopes (gains), and a quad comparator
LM339 to tell the output which one of the Op Amps is valid.....
>
>......An I-V converter chip for the input and a V-I converter chip for the output.
Is there a way to avoid this?......
>
Why would you need these converters? The input and output are voltage
signals.
An unpleasant feature of this solution is that each segment of the curve
has TWO parameters to set. These include the slope and the offset. For
a four segment curve one would have to mess around with eight adjusting
potentiometers. Any correction of gain or offset in any of the opamps
would change alignment of the corresponding curve sector in respect to
both neighbouring sectors. That means that if settings for any segment
were changed one would have to readjust all other segments, in order
to get a curve without kinks at the switching points. And to check if
adjustment is done correctly one would have to scan the input over the
whole range, and see if there are no output jumps at the op amp change
points, and if the slopes are as expected. It can be done but it is
rather messy
A microcontroller solution has that advantage that one can input
separately several slope parameters for the sectors of the curve, or
input the data points in a process of adding a gallon to the tank and
depressing a button, and leave the whole messy curve generation process
to the controller.
Jerzy
Jerzy
________________________________________________________________________________
| Subject: | Re: AutoPilot Disconnect Brain Teaser - |
Better than words is an illustration:
http://www.jwave.vt.edu/crcd/farkas/lectures/structure/tsld002.htm.
Although this is illustration shows how atoms are arranged in a crystalline
lattice it is the same concept as solid spheres being closely packed. In
FCC each of the six sides of the cube contains 1/2 of a sphere for a total
of three, and the eight corners contribute eight eighths of a sphere for
another whole one. Calculate the volume occupied by the four spheres and
compare it to the volume of the cube and you get the 74.05% number.
Best regards,
Rob Housman
Europa XS Tri-Gear A070
Airfarame complete
Irvine, CA
-----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: Re: AutoPilot Disconnect Brain Teaser -
>
>The packing fraction for face-centered cubic packing is rho0.7405. Adjust
>results accordingly.
>
>Eric
You threw me a new one there Eric. Care to describe "packing fraction"
in 25 words or less? ;-)
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
| Subject: | Re: AutoPilot Disconnect Brain Teaser - |
>>
>>The packing fraction for face-centered cubic packing is rho0.7405. Adjust
>>results accordingly.
>>
>>Eric
>You threw me a new one there Eric. Care to describe "packing fraction"
>in 25 words or less? ;-)
>Bob . . .
Sure:
Well, If you put a bunch of balls in a box, they achieve a packing that is better
than all-lined-up in straight rows and columns. (25 words.)
There are an infinite number of way to do this, but pure hexagonal packing is best
(hard to prove but easy to measure). When the cubic constraint is applied,
a face-centered cubic packing is most efficient (arranged like a diamond's carbon
atoms).
Illustrative brain teaser-- A cubic box holds a bowling ball. The bowling ball
is removed, melted down into very tiny spheres and the tiny balls poured back
into the box. To what level is the box filled ? Answer--That's easy! 74.05 percent
of the original volume.
Any "thought experiment" that arranges balls in purely cubic rows and column misses
the fact that the true number is 1/rho (where rho is the packing fraction)
times the rows-and-columns-result. Thus there are (1 / 0.7405) X 1 X 10
9 balls in the 1" cube.
Regards,
Eric M. Jones
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
| Subject: | non-Microprocessor based Fuel Gauge Linearizer |
Jerzy--Of course you are right. I was hoping this detail would fall into place,
since there are some issues yet to be resolved.
Bob and Jerzy and others. You would be right to guess I am more comfortable with
op amps than with microprocessors. I returned to using discrete chips after
receiving the source code for a device of similar complexity....and it is 25 pages
of assembler. The notion that using a microprocessor instead of a couple
of chips should best be argued upon the completion of parallel projects. Believe
me, I am wholeheartedly a microprocessor fan, but not in this design.
Besides....analog input, analog output, and don't a few op amps and comparators
make an analog "computer"?
Regards,
Eric M. Jones
"The natural progress of things is for liberty to yield and government to gain
ground."
-- Thomas Jefferson
________________________________________________________________________________
| From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
| Subject: | Static when Refuelling re Braid |
" Any help is kindly > appreciated, but I did buy the tinned copper braid today,
and
> after reading your message I don't know what to do with it. >
> Reg
> Tony Renshaw
That would be braid dangling inside the tank, wired to electrical ground? It won't
do anything during refueling to suppress static charges, since fuel is essentially
nonconductive.
Fred F"
This byplay brings to mind the accident report of the glider over S England hit
by lightning well clear of cloud. Basically it blew up. Admittedly, the strike
was a big one electrically, but the composition glider came to bits because
the bolt fllowed the control rods from aileron to cockpit (sound familiar?), burnt
the instructor's jacket collar and blew both occupants into the air. The
craft came down in bits and the boys in 'chutes - but the message was 'you don't
need fuel to blow it to bits, but you might need a 'chute".
I've got a printed version of the report here somewhere.
Ferg
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Diode failures and "Reliable Systems" |
>Diodes. . . . . I get a little excited when I hear stories of diodes
>failing.
>
>I've quoted the relevant parts above.
>
>Now, my anecdote, prior to asking a ques: Anecdote: While Avionics Officer
>for an A-7D unit, one of the Big Eight test stations (each of the eight
>costing about $1 million each) suffered a diode "short" on a circuit card.
>This simple 2 cent piece failed - resulting in high current flow in that
>circuit, which was not protected - designers didn't consider the diode
>failure mechanism. Well, the high current cascaded throughout the test
>station and resulted in something like a lightning strike on the entire test
>station. We spent months and LOTS of unit funds repairing that test
>station.
>
>Now, I'm in the role of home builder-designer of my RV-6 electrical system.
>And we've been talking many months about an Endurance Bus, with a diode
>allowing power to flow to the E-bus from the main bus, and to prevent
>battery drain from the E-bus to the main bus when main bus is shut down for
>alternator failure.
>
>A diode.
>
>I'll bet those who work in this field have other stories about diode
>failures.
>
>Are there some diodes that are better (more durable, longer lasting) than
>other diodes?
>
>What level of "diode spec" ought to be sufficient to avoid "typical" diode
>failures? Is "bigger" better?
>
>What are diodes most sensitive to? (that would cause them to fail)
>
>If I can't "rely" on the diode between Main & E busses, then I might
>consider "adding parts count" to detect failure of this critter; or special
>pilot operating procedures to use voltmeter wired to specific, switch
>selectable places, with opening and closing of e-bus switch or other means
>of verifying, on every flight, that the diode is function correctly. (Do I
>smell my own paranoia oozing out?)
>
>David Carter
It's always useful to critique anecdotal data if only to
discover that there is no useful data contained therein.
Looking at the above I would offer the following observations
and perhaps folks out there can cite others:
We've all heard about the nation that was lost for want
of a nail in a horseshoe . . . a classic analogy of
cascaded failures. There is always potential and even
probability that one failure will propagate to the
destruction of other components of a system. If any
single failure can take the system down, our consideration
as flight-system designers is to build firewalls between
the failed system and the rest of the aircraft. For
most instances, a fuse or circuit breaker is all that's
needed to prevent the worst kind of failure in any one
system from having a deleterious effect on other systems.
As soon as you run a wire from one system to another,
then a degree of interdependency has been created
that must be considered in your failure mode effects
analysis. For example: if the GPS receiver goes down, will
my wing-leveler retain any degree of usefulness as
an aid to operating this airplane . . . or does it
become useless too?
So, what can we learn about a 2-cent diode that
caused so much grief in the anecdote cited above:
We don't know the details of how this "nail" failure
propagated across the host system or ancillary
systems . . . but if the cost to fix included months
of repair time and lost-of-use time, it's reasonable
to conclude that damage was extensive. It raises
a further question about whether or not the design
flaw was corrected to make it more tolerant of such
failures . . . or were the failed systems simply
repaired leaving a potential for the same failure
to happen again?
Given that the anecdote cites a diode as the
first event in this cascade failure, is this
a rational reason for extra-ordinary attention
to the use of diodes in our little airplanes?
Further, is there anything to suggest that
other components are not equally deserving
of similar attention. It's conceivable that
the very same story could be repeated with the
phrase "2-cent resistor" substituted for "2-cent
diode."
When we design systems for Part 25 and higher
duty service, were obligated by decree to consider
MULTIPLE failures weighed with each other in
reliability analysis . . . presumably to demonstrate
that in spite of any two failures, our design is
is robust enough to run 1,000,000 hours failure
free . . . any skeptics out there?
Sooo . . . rather than wrap ourselves around
the axles of reliability studies that take lots
of research, time and probably don't mean much
anyhow, the OBAM community has deduced that
it's easier to ASSUME that parts of our
system are going to fail and that the
goal is to configure for failure tolerance
as opposed to failure proof. Something
akin to breeding war horses that fight well
on three legs.
Yup, that diode between the main-bus and e-bus
is NOT IMMUNE FROM FAILURE. In what ways can
it fail? (OPEN or SHORT). How do we know it
has failed (E-BUS STUFF GOES DARK for open
and (E-BUS ALT FEED TEST IN PREFLIGHT POWERS
THE MAIN BUS - for shorted). What are the
consequences of either failure mode? (IF
SHORTED WHILE AIRBORNE - probably not
noticed . . . but we'll catch it at next
preflight) (IF OPEN WHILE AIRBORNE - e-bus
goodies go dark and we have to close the
alternate feedpath switch for continued
operation).
Okay, assuming you can deduce no errors
of reasoning in the analysis above, how does
this affect your concerns about diode
reliability in this particular case?
If failure concerns are adequately addressed
we can turn our attention to reducing likelihood
of failure as a sort of icing-on-the-cake . . .
i.e. were not trying to improve reliability
with an eye on flight comfort but more as
a reduced maintenance issue.
The smallest diode array that comes in the
package I suggest is rated at 25A . . . you can
buy these rectifier arrays in ratings up to
35A. Sooo . . . unless you have everything
but the kitchen sink powered from the e-bus,
our diode is very adequately de-rated.
The lowest voltage offered by any diode manufacturer
is 50V . . . plenty of headroom for our 14V
application. These critters have a voltage drop
so they dissipate heat. Can't hang 'em out in
the air . . . so bolt it down to a metallic
surface.
Wrap-up: We've made a considered selection of
the component and its installation with a
eye toward robustness. Further, we've
deduced that failure of the component
is no more than a nuisance.
Going back to the 2-cent diode bringing
down $millions$ worth of equipment. How is
this anecdote relevant to how a $5 diode
is bolted to your airplane?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: SD-8 Alternator Questions |
>
>
>This recent discussion on dual batteries vs. dual alternators had me
>thinking about the system that I am planning. I'll be using the "All
>Electric on a Budget" except with an internally regulated alternator (with
>OVM and another big contactor), but my question is about the SD-8. I have
>assumed that the SD-8 is a true permanent magent alternator which means that
>if you spin it, it will make juice. Is this true?
yes . . . but it's regulator senses the bus-side . . .
>I have heard bits and pieces of debate on this list about the SD-8 requiring
>power to get started but then the battery can go away after the unit is
>running and assuming a good filter it will produce decent power. I assume
>that these concerns are due to the fact that the relay will need some
>external source of power to get it closed, but once it is closed there is no
>further need of the battery. I guess I am challenging my own assumptions
>and want to understand this little alternator a little better.
. . . and doesn't bring the SD-8 on line unless there
is a battery present.
>I also read here once that it was not a good idea to start this little
>alternator during the pre-flight checks because then it will sit there and
>make power the whole flight and that this was somehow bad for it. I would
>really like to be able to check this little guy during the pre-taxi check
>list and would like to better understand what is going on inside it before I
>plunk down the money.
Not true . . . test it and run it any way you like.
>Although my engine will not totaly rely on electrical power my panel does.
>I'll be blind as the proverbial bat if I lose my electrical system.
>
>Oh BTW what was the answer to the water molecule ping pong ball question? I
>would guess they would be a few inches deep, but I barely passed Chemistry
>so I can't remember all that mole stuff.
I purposely left out one piece of data to see if anyone
remembered their chemistry. There is a physical constant
called Avagadro's number (Na = 6.022 times ten to the
23rd power) that defines the number of molecules in a gram-mole
of a substance. For example, oxygen molecules have an atomic
mass of 32. Therefore, an Avagadro's number of oxygen
molecules will have a mass of 32g. H20 has an atomic mass
of 16+1+1 or 18. So, an Avagadro's number of water molecules
is 18g. 1 cc of water is 1 gram so the cc of water has 1/18th of
an Avagadro's number of water molecules.
The rest is setting up the calculations to figure out the
total volume this number of ping-pong balls (Stacked in
planar rows - not nested) and dividing that volume by
the surface area of the US . . . give it a try. Trust me,
you'll be amazed by the number.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Cheap blind encoder. |
>
>
>HI All,
>
>I a getting a Micro air transponder, and was wondering what I should do
>for encoder and antenna, in a glass plane
Look at the ACK model A-30. The street price on these is
about $175. Don't know of anything less expensive.
Bob . . .
________________________________________________________________________________
| From: | "Bob Kuc" <bkuc1(at)tampabay.rr.com> |
Bob ...
Did you ever receive my Wig Wag package for you to check? It has been a few weeks.
Thanks
Bob K
________________________________________________________________________________
| Subject: | Re: Cheap blind encoder. |
Companion encoder question: Panel will have a transponder and a GNS430. Both require
input from an encoder. Can the two units be paralleled to the same encoder
(two wires from each encoder pin) or does the typical installation have two
encoders?
Dan
________________________________________________________________________________
| Subject: | Re: Flap system failure modes (Was circuit protection |
issues)
Bob,
Thanks for your help and your advice.
>
> Okay. I'm not sure you need to have an on-purpose limitation
> to the flaps as long as your pilots are aware how to use
> them safely. Benefits of flaps happen at touchdown. More
> flaps just makes you come down faster and leaves you with
> less energy to squander in the flare. If I were a flight
> instructor, I'd not let a student use flaps at all until
> they were proficient without them.
>
> In the older C-150's, you could get the best of both
> worlds by hanging out no more drag than you can tolerate
> at full throttle to arrest your descent. When you're
> sure you have the landing made, put out the rest of
> the flaps.
>
That's the way we use them in this country.
We intend to use the full flap position only for particular landing
conditions.
> >
> >I guess you and I know too well....
>
> Okay, let's see what we can do to make failures as tolerant
> as possible. I think I'd simply wire all four motors in
> parallel with each other. Treat them as a single motor.
> Drive the system through a single, 20A breaker at the bus.
> The idea of protecting each motor in any way is scary. You
> don't want the system to continue to run in any way if one
> motor has decided to mis-behave.
>
Yes of course. Indeed my intention to wire them in parallel.
My question was about the sizing of the fuse and the wires, considering
fuses are faster than breakers ("the others" are using a breaker)
> My sense is that this little airplane simply cannot need
> as much snort as a 20A breaker would suggest. Wire with
> 14AWG wire and put a 20A breaker in for now. During flight
> testing, let's put an ammeter in and see what the system
> REALLY needs.I wouldn't be surprised to see that we can
> drop the breaker size down to 15 or even 10 amps. An
> RV actuator runs at under 5A.
Will do.
You don't need to size the
> breaker for inrush currents.
Is it the same for fuses ? I'm using fuseblocks, and the only breaker on
board is for the alterrnator OV protection. Or do I need to use a breaker
for the flaps ?
>
> If one wanted to reduce the hazards of single motor
> failure, we could design some fancy circuitry to sense
> abnormal operation and shut the whole system down
> when it was detected.
>
> Single point protection combined with judicious use
> of flaps in approach-to-landing should let you make the
> best of a rather un-thoughtful design. This wouldn't be
> the only airplane flying around with idiosyncrasies
> capable of embarrassing you or driving your pucker
> factor up. Take a checkout in a Tri-Pacer or a AA-1
> Yankee and have the check pilot show you how easy it
> is to get tense in these airplanes. They ain't your
> grandfather's C-172.
>
> If this system has a satisfactory history . . . meaning
> that gear-boxes aren't shelling out and motors are
> hanging in there, then you're not facing gross design
> limits or high rates of infant mortality. This suggests
> that until a motor or gearbox reaches wear-out,
> you won't have to shoulder duties as a failure modes
> test-pilot soon. Maybe this won't happen until after you've
> sold the airplane.
>
Let's hope so !
Thank you,
Gilles
________________________________________________________________________________
| From: | "John Karnes" <jpkarnes(at)charter.net> |
| Subject: | Re: OV circuit breaker tripping |
Bob and Cy-
Today I bypassed the B-load contactor and went directly to the starter
contactor from the alternator. I got about 14 volts without any circuit
breaker tripping. My problems appear to be centered around the B-load
contactor. The diode was about 100 ohms, so I don't think that is the
problem. Maybe the contactor itself or the 80 amp fuse???
John Karnes
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: SD-8 Alternator Questions |
>
>. . . but it's regulator senses the bus-side . . .
>
>
> . . . and doesn't bring the SD-8 on line unless there
> is a battery present.
>
>
> Bob . . .
Yep that is the piece that I was missing. I didn't think about the
regulator. Why would the regulator be built to inhibit the alternator
unless there was bus voltage? I must be missing something because it looks
like if the regulator saw zero volts it's 'brain' would tell it to do what
it took to bring the volts up to setpoint.
Does the "All Electric on a Budget" circuit have a single point of failure
in the fat wires coming off of the battery? Not that there is much chance
of either of those wires failing, but I am curious. I guess if the battery
ground wire came loose then the primary alternator would still yield some
volts but how ugly would running the main alternator without the battery be?
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Flap system failure modes (Was circuit protection |
issues)
> > My sense is that this little airplane simply cannot need
> > as much snort as a 20A breaker would suggest. Wire with
> > 14AWG wire and put a 20A breaker in for now. During flight
> > testing, let's put an ammeter in and see what the system
> > REALLY needs.I wouldn't be surprised to see that we can
> > drop the breaker size down to 15 or even 10 amps. An
> > RV actuator runs at under 5A.
>
>Will do.
>
>You don't need to size the
> > breaker for inrush currents.
>
>Is it the same for fuses ? I'm using fuseblocks, and the only breaker on
>board is for the alterrnator OV protection. Or do I need to use a breaker
>for the flaps ?
Hmmmm . . . Without specific measurements on your
group of 4 motors, I'm reluctant to offer an
opinion. With the right gear ratio, ONE of those
motors will run the flaps. In fact, the actuator
popular with RV builders uses a ball-screw that
is so efficient that a motor about the same size
runs the flaps with very little current compared
to ANYTHING with worm or acme drive components.
Problem is that inrush is 4x that of a single
motor. They're small motors and will accelerate
right smartly but the inrush IS going to be
higher even if it is relatively short.
Let's go the 20A fuse. This will be easy to test
before you fly. Run flaps to mid position. Then
do a series of flap drive operations for just a
second or so each direction. Delay long enough
between pulses to let the motors come to a stop.
If the fuse stays in place with a couple dozen
short term reversals over a period of a minute
or so, then it's going to be okay with respect
to in-flight operations.
Once the ground test is complete, we can go after
the flight data to see if we have a justification
for scaling the fuse to any lower value.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>Bob ...
>
>Did you ever receive my Wig Wag package for you to check? It has been a
>few weeks.
>
>Thanks
>
>Bob K
Yes. I can wasn't able to get your assembly to mis-behave.
Poked around on it a bit but no change. It's still on the
bench. I'd like to keep it here for further investigation.
I'm sending you one I built that's about 1/6th the size
and potted for ruggedness. It's the prototype for an article
on w/w module I started a few months ago before I found the
electronically driven relays.
The new module and your original relays will go out this
evening.
Bob . . .
________________________________________________________________________________
| From: | "Bob Kuc" <bkuc1(at)tampabay.rr.com> |
Thanks Bob, Onething that I did notice after I sent this out was that I was
only supply 10 Volts throught it. Since I am still building and not engine
yet, I am stuck at battery power. However, my batery is perty weak, Maybe
the low volts is through more amps through there and causin the
mis-behaving.
Bob
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: Wig wag
>
> >
> >Bob ...
> >
> >Did you ever receive my Wig Wag package for you to check? It has been a
> >few weeks.
> >
> >Thanks
> >
> >Bob K
>
> Yes. I can wasn't able to get your assembly to mis-behave.
> Poked around on it a bit but no change. It's still on the
> bench. I'd like to keep it here for further investigation.
> I'm sending you one I built that's about 1/6th the size
> and potted for ruggedness. It's the prototype for an article
> on w/w module I started a few months ago before I found the
> electronically driven relays.
>
> The new module and your original relays will go out this
> evening.
>
> Bob . . .
>
>
________________________________________________________________________________
| Subject: | Cheap blind encoder. |
What inputs does your transponder and GNS430 accept, Gray code, serial or
both? I just installed UPS gear in my Navion and the SL70 transponder will
accept either Gray code or serial encoder input and output a serial signal
to the GX60 GPS/Com (it only accepts serial). That let me use my existing
(and cheap) Ameriking AK-350 encoder instead of an expensive serial encoder
or serial converter and still have the altitude input needed for IFR
approval. I suspect Garmin may have similar capability. It's an option to
explore.
Regards,
Greg Young - Houston (DWH)
RV-6 N6GY ...project Phoenix
Navion N5221K - just an XXL RV-6A
>
> Companion encoder question: Panel will have a transponder and
> a GNS430. Both require input from an encoder. Can the two
> units be paralleled to the same encoder (two wires from each
> encoder pin) or does the typical installation have two encoders?
>
> Dan
>
________________________________________________________________________________
| From: | Kent Ashton <kjashton(at)vnet.net> |
| Subject: | Re: Static when Refuelling re Braid |
>
>
>" Any help is kindly > appreciated, but I did buy the tinned copper braid today,
and
> > after reading your message I don't know what to do with it. >
> > Reg
> > Tony Renshaw
>
For fiberglass airplanes, If you rivet the braid, or any wire, to
the fuel cap ring and bring it down to some central point, like in the
cockpit strake area or the external step, you can at least ground the
fuel cap to prevent static sparking between the refueling nozzle and the
cap ring. Should help some.
--Kent A.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>Thanks Bob, Onething that I did notice after I sent this out was that I was
>only supply 10 Volts throught it. Since I am still building and not engine
>yet, I am stuck at battery power. However, my batery is perty weak, Maybe
>the low volts is through more amps through there and causin the
>mis-behaving.
Hmmm . . I'll try that and see what happens.
. . . in any case, the other flasher went out
a few minutes ago.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: SD-8 Alternator Questions |
>
>
> >
> >. . . but it's regulator senses the bus-side . . .
> >
> >
> > . . . and doesn't bring the SD-8 on line unless there
> > is a battery present.
> >
> >
> > Bob . . .
>
>Yep that is the piece that I was missing. I didn't think about the
>regulator. Why would the regulator be built to inhibit the alternator
>unless there was bus voltage? I must be missing something because it looks
>like if the regulator saw zero volts it's 'brain' would tell it to do what
>it took to bring the volts up to setpoint.
That's what they did. It's a purchased regulator Bill gets
from some outfit in Kansas City as I recall. Perhaps the rational
for the design was to make sure that any time the alternator
was delivering useful power, the presence of a battery
made sure it was as clean as practical.
I've got some ideas about how to get a few more watts out of
and SD-8 with a regulator that would provide quite smooth
power sans battery. I'll keep that on the back burner as
a potential product.
>Does the "All Electric on a Budget" circuit have a single point of failure
>in the fat wires coming off of the battery? Not that there is much chance
>of either of those wires failing, but I am curious.
There is that risk. I've never had or seen a wire come loose
but a list member broke a post off a 17 a.h. RG battery and
reported on it here a few weeks ago. Obviously, the chances
are not zero. If it were my airplane, I'd use 4AWG welding
wire battery jumpers to get soft, flexible leads.
> I guess if the battery
>ground wire came loose then the primary alternator would still yield some
>volts but how ugly would running the main alternator without the battery be?
Hard to quantify. You can certainly run the experiment
after the airplane is built and see. If you don't
like what you see, you can always add the tiny aux
battery to accommodate that condition.
Keep in mind that about 100,000 S.E. aircraft are
flying around out there now with one altenrator, one
battery and the same risk for loss of system due to
battery coming unhooked. It's much more likely that
you'll get alternator or contactor failure than
failure of wires on the battery. So an all-electric-
on-a-budget architecture is waaaaayyyyyy more reliable
than anything flying around in spam-can-land.
Consider too that for most of the way we use our
airplanes, TOTAL loss of electrical system can be
tolerated. I normally use hand-held GPS to navigate
and I carry a hand-held VOR/COM. When I walk up to
a rental airplane, there's no practical way for me
to assess the condition or history of that ship's
electrical system. If I can fly a J-3 somewhere
with no electrical system, I can fly an A-36
too.
Bob . . .
________________________________________________________________________________
| Subject: | SD-8 Alternator Questions |
When I took P. Chem Avagadro's number was 6.0238 X 10 E 23
Best regards,
Rob Housman
Europa XS Tri-Gear A070
Airfarame complete
Irvine, CA
-----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: SD-8 Alternator Questions
SNIP
I purposely left out one piece of data to see if anyone
remembered their chemistry. There is a physical constant
called Avagadro's number (Na = 6.022 times ten to the
23rd power) that defines the number of molecules in a gram-mole
of a substance.
SNIP
Bob . . .
________________________________________________________________________________
| From: | Charlie & Tupper England <cengland(at)netdoor.com> |
| Subject: | Re: Static when Refuelling re Braid |
Fergus Kyle wrote:
>
>" Any help is kindly > appreciated, but I did buy the tinned copper braid today,
and
> > after reading your message I don't know what to do with it. >
> > Reg
> > Tony Renshaw
>
>That would be braid dangling inside the tank, wired to electrical ground? It
won't do anything during refueling to suppress static charges, since fuel is essentially
nonconductive.
>Fred F"
>
snipped
I haven't followed this thread, but this caught my eye. The static
discharge problem is *caused* by the fact that fuel is basically non
conductive. A glass rod is non conductive, but we've all seen the
effects after rubbing one through a cat's fur.
Either the fuel or the plane can have a static charge. If they are at a
different voltage potential, the chance of a spark exists as the nozzle
approaches the tank. The fuel can acquire a charge as it moves through a
hose, just like the glass rod through fur.
If you don't bring the fuel delivery system & the plane to the same
voltage potential before beginning the refueling process, you can get a
spark. That's why the line boy grounds the truck and grounds the plane
before fueling begins.
Charlie
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | RE: Avogadro's Number |
>
>When I took P. Chem Avagadro's number was 6.0238 X 10 E 23
>
>
>Best regards,
A check of my 41st edition (1960) edition of the
CRC Handbook calls it 6.0247*10E23 . . . and I
seem to recall using 6.025*10E23 in class.
. . . but a search on the 'net yields
6.022136736*10E23
http://education.jlab.org/glossary/avogrado.html
http://www.britannica.com/ebc/article?eu=381538
You know how those guys are. There are folks who can
spend a lifetime refining a single idea. Avogadro's
idea seems to have moved a tad. Does the value
of Na we carved into the gray matter date when we
all took chemistry?
Bob . . .
________________________________________________________________________________
| From: | "Dave Ford" <dford(at)michweb.net> |
I am at the stage of integrating wiring of instruments and have noticed I have
three instruments requesting encoded altitude information from the encoder.
Can the encoder output be daisy-chained or paralleled to each instrument needing
that information? Is isolation required via resistors? Is an altitude
encoder capable of its information going to more than one device without loading
its output?
Dave Ford
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: encoder wiring |
In a message dated 5/14/03 8:52:41 PM Central Daylight Time,
dford(at)michweb.net writes:
> I am at the stage of integrating wiring of instruments and have noticed I
> have three instruments requesting encoded altitude information from the
> encoder. Can the encoder output be daisy-chained or paralleled to each
> instrument needing that information? Is isolation required via resistors?
> Is an altitude encoder capable of its information going to more than one
> device without loading its output?
>
> Dave Ford
>
Good Evening Dave,
I know nothing about wiring problems, but I have been involved with that
problem in the past. You can feed them all by using parallel wiring. My
recollection is that it takes about eleven wires to each device. Just double
up on the pins and take it on to the next device. One caution, there are
some transponders that tend to have a back feed interference of some sort.
Specifically, the King KT-76 series. For those, it is advisable to put
diodes in the input lines to the transponder so that the data can only go
into the transponder and not flow back out. Eleven little 1N4001s will do
the job just fine. Anything up to 1N4009s is supposedly OK.
Maybe one of those who know what is happening will comment further.
Happy Skies,
Old Bob
________________________________________________________________________________
| Subject: | Re: RE: Avogadro's Number |
| From: | Don Boardman <dboardm3(at)twcny.rr.com> |
> seem to recall using 6.025*10E23 in class.
> . . . but a search on the 'net yields
> 6.022136736*10E23
> You know how those guys are. There are folks who can
> spend a lifetime refining a single idea. Avogadro's
> idea seems to have moved a tad. Does the value
> of Na we carved into the gray matter date when we
> all took chemistry?
>
> Bob . . .
Tomorrow I will enjoy telling my 33rd. group of chemistry students that
Avogadro's number is alive and well on the Internet list serve circuit!
I tell them all the time that it is a number they better remember for life,
and that if I run into them when they are older I will expect them to rattle
it off in style.
5 weeks to retirement.
Regards,
Don Boardman
Murphy Moose #130 M-14PF 400HP, MT-prop, Aerocet 3500 amphibs,
AeroElectric Wired, Rome, NY
________________________________________________________________________________
| Subject: | RE: Avogadro's Number |
My P. Chem. text shows a copyright date of 1961 (and shows only four decimal
places). I knew a lot of the practical stuff I learned is outdated but I
thought the basic stuff should have remained constant. Oh well.
Best regards,
Rob Housman
Europa XS Tri-Gear A070
Airfarame complete
Irvine, CA
-----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: AeroElectric-List: RE: Avogadro's Number
<RobH@hyperion-ef.com>
>
>When I took P. Chem Avagadro's number was 6.0238 X 10 E 23
>
>
>Best regards,
A check of my 41st edition (1960) edition of the
CRC Handbook calls it 6.0247*10E23 . . . and I
seem to recall using 6.025*10E23 in class.
. . . but a search on the 'net yields
6.022136736*10E23
http://education.jlab.org/glossary/avogrado.html
http://www.britannica.com/ebc/article?eu=381538
You know how those guys are. There are folks who can
spend a lifetime refining a single idea. Avogadro's
idea seems to have moved a tad. Does the value
of Na we carved into the gray matter date when we
all took chemistry?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: OV circuit breaker tripping |
>
>Bob and Cy-
>
>Today I bypassed the B-load contactor and went directly to the starter
>contactor from the alternator. I got about 14 volts without any circuit
>breaker tripping. My problems appear to be centered around the B-load
>contactor. The diode was about 100 ohms, so I don't think that is the
>problem. Maybe the contactor itself or the 80 amp fuse???
Hmmm . . . perhaps there's a short inside the contactor.
I've heard of such things but never seen them. Disconnect
all the wires from the small terminals of the contactor
and measure the resistance between the two terminals and then
from each terminal to the contactor case and tell us what you
find.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Cheap blind encoder. |
>
>Companion encoder question: Panel will have a transponder and a
>GNS430. Both require input from an encoder. Can the two units be
>paralleled to the same encoder (two wires from each encoder pin) or does
>the typical installation have two encoders?
You can drive multiple loads with one encoder but you need an array of
diodes to avoid cross-coupled problems between loads. I don't
recall now exactly how the diodes are oriented. I searched the
net and found some encoder loads (transponders) that claim
to have isolation diodes installed.
I'll call around and see if an avionics wienie can tell me
of the top of his head which way the diodes have to go . . .
Opps, just found an overhaul manual for an encoder on the
'net at:
http://www.trans-cal.com/7421%20B.pdf
on page 2 it speaks of open collector outputs which
are active pull down only devices and that the pull-up
for logic "hi" is expected to come from the transponder
(signal load). This means that isolation diodes would
have to be included in the data lines for each device
that expects to get altitude data with the cathode
facing the encoder.
These diodes prevent the data lines from being pulled
to ground by a transponder or GPS that is powered down.
I've published an exemplar diagram at
http://216.55.140.222/temp/Encoder.pdf
The neatest way to install this raft of diodes
is to lay out a simple etched circuit board with
d-sub connector to bring wires onto and off the
board. For driving two loads, there's a total
27 wires . . . a single 37-pin D-sub would
do it.
I've seen some "professional" installations
where the diodes were simply butt-sliced
into the wire bundles and covered with heat-
shrink. I guess some DER signed off on this
somewhere.
Be sure to check if the devices that need
altitude data for built in diodes. If they're
already present, then you can simply eliminate
the diodes show in the drawing and wire direct.
Bob . . .
>Dan
>
>
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: encoder wiring |
>
> I am at the stage of integrating wiring of instruments and have
> noticed I have three instruments requesting encoded altitude information
> from the encoder. Can the encoder output be daisy-chained or paralleled
> to each instrument needing that information? Is isolation required via
> resistors? Is an altitude encoder capable of its information going to
> more than one device without loading its output?
See my earlier on this subject. If your device needing
altitude has isolation diodes already installed, it
can be simply paralleled with the other devices. Otherwise
you need to add them per the example at:
http://216.55.140.222/temp/Encoder.pdf
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: non-Microprocessor based Fuel Gauge |
Linearizer
>
>Jerzy--Of course you are right. I was hoping this detail would fall into
>place, since there are some issues yet to be resolved.
>
>Bob and Jerzy and others. You would be right to guess I am more
>comfortable with op amps than with microprocessors. I returned to using
>discrete chips after receiving the source code for a device of similar
>complexity....and it is 25 pages of assembler. The notion that using a
>microprocessor instead of a couple of chips should best be argued upon the
>completion of parallel projects. Believe me, I am wholeheartedly a
>microprocessor fan, but not in this design.
Hmmm . . . I'll bet the code to read an a/d, get the first
lookup table values above and below the reading and average
them for output to a d/a wouldn't fill one page.
>Besides....analog input, analog output, and don't a few op amps and
>comparators make an analog "computer"?
There are some single chip processors with an a/d and
d/a built in that would do this. Check out the PIC12F675
data sheet at
http://www.microchip.com/download/lit/pline/picmicro/families/12f6xx/41190c.pdf
and application tips at:
http://www.microchip.com/download/lit/pline/picmicro/families/12f6xx/40040b.pdf
This device sells for under $3 from Digikey and will do about
everything you need to do in one chip . . . in fact, it
might be possible to do a DUAL linearizer in the same chip
so that both tanks can be calibrated on one assembly.
You can talk to the a/d directly from the tank sender
driven by a constant current source. A relatively simple
routine to drive a fet with a variable duty-cycle would
provide for analog i/o to drive the standard gage that
comes with the senders.
The hardest part would be to write the program to go into
a laptop for consumers to talk to the chip and modify its
lookup table. Visual Basic would probably help with a
user-friendly windows-like interface.
I'm finding it increasingly difficult to justify even
simple projects in analog and/or discrete logic parts
any more. The chips are just too cheap and getting
more powerful all the time.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | AutoPilot Disconnect |
>
>This analysis makes some simplifying assumptions; most importantly that the
>switch and relay contacts have zero resistance, and that the only non-purely
>resistive component is the relay coil. The calculation of the effect of
>these tertiary elements are left to the student.... ;-)
>
>
> >(is there a prize????) ;-) -john-
>
> Sure, after you finish the test . . .
>
> Bob . . .
You got it. Do you have a copy of the CD we
sell?
Bob . . .
________________________________________________________________________________
| Subject: | Re: non-Microprocessor based Fuel Gauge Linearizer |
No need for a laptop... just a switch to put it in calibrate mode, and a
serial EEPROM... and some PICs even contain those I think. Switch to
"calibrate" mode, have it light each bar of a bar-mode display
sequentially, then add the desired amount of fuel to be represrented by
that display element, and push a button to "capture" that A/D value -
let it build it's own lookup table.
Hmmm, maybe I'll make one.
-John R.
Robert L. Nuckolls, III wrote:
>
>
>
>>
>>Jerzy--Of course you are right. I was hoping this detail would fall into
>>place, since there are some issues yet to be resolved.
>>
>>Bob and Jerzy and others. You would be right to guess I am more
>>comfortable with op amps than with microprocessors. I returned to using
>>discrete chips after receiving the source code for a device of similar
>>complexity....and it is 25 pages of assembler. The notion that using a
>>microprocessor instead of a couple of chips should best be argued upon the
>>completion of parallel projects. Believe me, I am wholeheartedly a
>>microprocessor fan, but not in this design.
>>
>>
>
> Hmmm . . . I'll bet the code to read an a/d, get the first
> lookup table values above and below the reading and average
> them for output to a d/a wouldn't fill one page.
>
>
>
>
>>Besides....analog input, analog output, and don't a few op amps and
>>comparators make an analog "computer"?
>>
>>
>
>
> There are some single chip processors with an a/d and
> d/a built in that would do this. Check out the PIC12F675
> data sheet at
> http://www.microchip.com/download/lit/pline/picmicro/families/12f6xx/41190c.pdf
>
> and application tips at:
>
> http://www.microchip.com/download/lit/pline/picmicro/families/12f6xx/40040b.pdf
>
> This device sells for under $3 from Digikey and will do about
> everything you need to do in one chip . . . in fact, it
> might be possible to do a DUAL linearizer in the same chip
> so that both tanks can be calibrated on one assembly.
> You can talk to the a/d directly from the tank sender
> driven by a constant current source. A relatively simple
> routine to drive a fet with a variable duty-cycle would
> provide for analog i/o to drive the standard gage that
> comes with the senders.
>
> The hardest part would be to write the program to go into
> a laptop for consumers to talk to the chip and modify its
> lookup table. Visual Basic would probably help with a
> user-friendly windows-like interface.
>
> I'm finding it increasingly difficult to justify even
> simple projects in analog and/or discrete logic parts
> any more. The chips are just too cheap and getting
> more powerful all the time.
>
> Bob . . .
>
>
>
>
________________________________________________________________________________
| Subject: | Re: Cheap blind encoder. |
Thanks Greg, Bob, and Bob.
Interesting that Dave had the same encoder interconnect question. Good
example of Bob's Theory: Put it on-list, perhaps help many people.
Bob, appreciate for the diode diagram. BTW, the GNS430 install manual
makes mention of the need for diodes with some encoders and transponders, but
doesn't mention which ones. Here's the notation: "Some transponders and
other altitude encoder receivers do not have internal isolation diodes to
prevent the unit form pulling the encoder lines to ground when the unit is
off. These units require a diode added to the installation harness for each
encoder line. The anode should be connected on the receiving unit's side
and the cathode should be connected onthe encoder side. A set of diodes is
required for each unit without internal diodes. The 400 Series unit includes
internal diodes for isolation of the encoder lines." For anybody needing the
manual, it is on the web at http:/www.garmin.com/manuals/143.pdf. No link on
the Garmin website, but it's there.
I supppose another approach might be to simply purchase a second
encoder for $175. Wire one to the transponder, the other to the 430.
Greg, the 430 does have an RS232 input, but I don't think the existing
transponder has the output. I'll check. Garmin's "typical install" has grey
code from encoder to their GTX327, the RS232 from there to the 430.
Quick follow-up on two previous posts. I asked about a pinout for a
WX900 Stormscope. Turns out to be available for the asking, in pdf format.
Email Vicky.Miller(at)goodrich.com. Richard, thanks for the offer.
The other question was about wiring radios together without an audio
panel. The main issue was lack of panel space. Found out the PS4000 was
only 2.5 x 1.75, so my buddy ordered one from Chief at $660. I'll let you
know how we like it when the airplane flies.
Dan Horton
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: non-Microprocessor based Fuel Gauge |
Linearizer
><jrourke@allied-computer.com>
>
>No need for a laptop... just a switch to put it in calibrate mode, and a
>serial EEPROM... and some PICs even contain those I think. Switch to
>"calibrate" mode, have it light each bar of a bar-mode display
>sequentially, then add the desired amount of fuel to be represrented by
>that display element, and push a button to "capture" that A/D value -
>let it build it's own lookup table.
>
>Hmmm, maybe I'll make one.
>
>-John R.
Good idea. I think the 12F675 will let you write to it's
own flash memory space. I don't think it needs any external
ROM to store your user generated lookup table. Driving
a bar-graph with the 12F675 is problematical if you're
interested in low parts count . . . due to limited i/o
on the chip, you'd have to add an external shift register
to drive each display. . . . Of course, there are larger
PICs with more i/o . . . they might even cost as much as
$10 a chip.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Cheap blind encoder. |
>
>Thanks Greg, Bob, and Bob.
>
> Interesting that Dave had the same encoder interconnect
> question. Good
>example of Bob's Theory: Put it on-list, perhaps help many people.
>
> Bob, appreciate for the diode diagram. BTW, the GNS430 install manual
>makes mention of the need for diodes with some encoders and transponders, but
>doesn't mention which ones. Here's the notation: "Some transponders and
>other altitude encoder receivers do not have internal isolation diodes to
>prevent the unit form pulling the encoder lines to ground when the unit is
>off. These units require a diode added to the installation harness for each
>encoder line. The anode should be connected on the receiving unit's side
>and the cathode should be connected onthe encoder side. A set of diodes is
>required for each unit without internal diodes. The 400 Series unit includes
>internal diodes for isolation of the encoder lines." For anybody needing the
>manual, it is on the web at http:/www.garmin.com/manuals/143.pdf. No link on
>the Garmin website, but it's there.
>
> I supppose another approach might be to simply purchase a second
>encoder for $175. Wire one to the transponder, the other to the 430.
Thanks for the confirmation of my midnight analysis last
night. It's pretty easy to test your transponder or GPS
for the existence of diodes. Hook a 9v battery in series
with a 10K resistor and hook the (+) end of this test
fixture to one of the altitude data input pins and the
(-) end to signal ground. Measure the voltage at the
data input pin with a digital voltmeter (very high input
impedance). It should read battery voltage. If diodes are
not present it will read substantially lower.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Interference |
>
>Bob et al: First background one: I built a LongEZ some 20 years ago and
>have learned to live with some quirks with the electrical system. For
>example when I transmit the fuel low lites come on and the Navaid autopilot
>rolls into a 30 degree bank. I gave up trying to find these uninvited bugs
>and have learned to enjoy them as part of life's little surprises.
>Background two: a friend has just completed a beautiful Lancair IVP with a
>very professional wiring job. When he transmits his SFS fuel indicators go
>to zero (while using the bottom, externally mounted antenna, not when using
>the antenna mounted inside the tail). He has been trouble shooting for a few
>weeks but so far no luck. Now to the point: I am just about ready to string
>wires and add an external com antenna to my Lancair IV and would like to
>avoid repeating these interference problems (EMI??). Advice? Does and
>don'ts? Are these quirks just part of life with a plastic airplane? Are
>they the result of multiple grounds, insufficient wire shielding, bad antenna
>installation, com coax too close to other wires, or too few chicken bones
>tossed during the build process? all help is appreciated--paul
Root causes of RFI problems fall into two categories. (1) something
in the installation of the offending transmitter has flooded the
panel and cockpit with RF levels much higher than the victims
were qualified to withstand. A common fault in this category is to
have the shield come loose in the coax connector at the back of
the transmitter. The transmission line becomes an antenna radiating
directly into ship's wiring.
The other, and much more common condition arises from the manufacture's
inattention to detail in crafting his product. Potential for
RFI was poorly considered (if at all).
The concerns you cited above are not strong contenders for root
cause mitigation. As a general rule, try to put as much physical
separation between antennas and cockpit . . . but this has
obvious limitations. Beyond that, one has to be prepared to
add filtering to some products i/o wiring where the manufacturer
hasn't done his homework.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Radio Noise Redux |
>
>
>Hi Folks,
> I've made a bit of progress on the noises I was hearing in my
> headsets. My main problem continues to be on the transmission
> side...sometimes fine, sometimes unintelligable. The intermittent
> nature of the beast is the most frustrating part. I've never been able
> to hear what people are reporting, but i think I've been able to
> duplicate what they tell me they hear.
> The MicroAir is powered from the essential bus, which in turn gets its
> power from the main bus via a diode as per Bob's drawings. With engine
> off, main contactors on, pushing the PTT results in a normal feedback in
> the headsets. When I start adding to the current load (e.g., Naviad,
> GPS, transponder) things get a little dicey. I start hearing terrible
> noises in the headset, but only very intermittently. When I then turn
> on one of the big current loads like the pitot heat or strobes, pushing
> the PTT switch switch gives me continuous loud growling sounds....voice
> can barely be made out. At this point the Grand Rapids EIS is showing
> 11.9 v or thereabouts.
> This at least seems logical. The radio doesn't get enough electrons,
> I guess, to tranmit properly. The problem is, why might this be
> happening with the engine on in flight? Yesterday in flight someone
> reported my transmission as unreadble, with loud background noise. At
> that time the EIS read 14.5 v. Twenty minutes earlier I got a report
> that my transmission was clear, with a small amount of background static.
Try the dry-battery for in-flight power of the Microair . . . I'm not
getting any pieces of the puzzle you've laid out above to fit into
any particular picture. I'm skeptical that it's a "diode problem" . . .
This technique has been used for bus-isolation for over 30 years
with great success.
> Could there be a problem with the diode? I'm not sure if they fail
> in an all-or-nothing way or if you can see a "partial." failure. I've
> used Bob's idea of hooking two 6 volt batteries together to power the
> radio separately from the busses. That helped me in isolating some of
> the the odd noises I was getting in the headset. However, I've never
> used those batteries to power the radio in flight. It seems like it
> would be easy enough to test-out this diode theory...just by-pass the
> thing and power the essential bus with a simple wire from the main bus
> for a while. But am I barking up the wrong tree here? Another
> Glastar/Subaru owner has replaced his diode due to a failure.
Hmmm . . . I'd like to talk to him . . .
Bob . . .
________________________________________________________________________________
| From: | "Ian Scott" <jabiru22(at)yahoo.com.au> |
| Subject: | non-Microprocessor based Fuel Gauge Linearizer |
What about calibrating the analogue gauge in a non linier fashion?
Low parts count, nothing to fail.
Perfectly calibrated and only costs the replacement face in a gauge. (or
a bit of paper).
Ian
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Eric
M. Jones
Subject: AeroElectric-List: non-Microprocessor based Fuel Gauge
Linearizer
-->
Jerzy--Of course you are right. I was hoping this detail would fall into
place, since there are some issues yet to be resolved.
Bob and Jerzy and others. You would be right to guess I am more
comfortable with op amps than with microprocessors. I returned to using
discrete chips after receiving the source code for a device of similar
complexity....and it is 25 pages of assembler. The notion that using a
microprocessor instead of a couple of chips should best be argued upon
the completion of parallel projects. Believe me, I am wholeheartedly a
microprocessor fan, but not in this design.
Besides....analog input, analog output, and don't a few op amps and
comparators make an analog "computer"?
Regards,
Eric M. Jones
"The natural progress of things is for liberty to yield and government
to gain ground."
-- Thomas Jefferson
direct advertising on the Matronics Forums.
________________________________________________________________________________
| From: | "Ian Scott" <jabiru22(at)yahoo.com.au> |
| Subject: | Feedback on the active noise headset conversion |
I was wondering if anyone had upgraded their normal headsets to active
noise reduction and what the results where like? I.e. the kit that
replaces the innards for your old headset.
Prices a paid & results and so on?
Thanks
Ian
________________________________________________________________________________
| From: | irampil(at)notes.cc.sunysb.edu |
| Subject: | Audio switch matrix |
05/15/2003 09:28:05 AM
Greetings,
I am hoping to utilize Bob's audio isolator/mixer circuit when it's
available.
Does anyone know of a source for a small (say 4 or 5 place) pushbutton
matrix
switch I can use to enable/disable inputs. A physically small linear array
would
be just what the doctor ordered ;-)
Ira
________________________________________________________________________________
| From: | "Ian Scott" <jabiru22(at)yahoo.com.au> |
| Subject: | Mizer fuel flow meter |
Hi all,
Does anyone know good or bad about the Mizer fuel flow meter, in a
carbureted (Jabiru) setup.
Thanks
Ian
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: SD-8 Alternator Questions |
> I've got some ideas about how to get a few more watts out of
> and SD-8 with a regulator that would provide quite smooth
> power sans battery. I'll keep that on the back burner as
> a potential product.
>
I'd be interested. I really like the idea of that alternator being self
contained. I also like the words "more watts" (argh, argh, argh).
>
> >Does the "All Electric on a Budget" circuit have a single point of
failure
> >in the fat wires coming off of the battery? Not that there is much
chance
> >of either of those wires failing, but I am curious.
>
> There is that risk. I've never had or seen a wire come loose
> but a list member broke a post off a 17 a.h. RG battery and
> reported on it here a few weeks ago. Obviously, the chances
> are not zero. If it were my airplane, I'd use 4AWG welding
> wire battery jumpers to get soft, flexible leads.
>
>
> > I guess if the battery
> >ground wire came loose then the primary alternator would still yield some
> >volts but how ugly would running the main alternator without the battery
be?
>
> Hard to quantify. You can certainly run the experiment
> after the airplane is built and see. If you don't
> like what you see, you can always add the tiny aux
> battery to accommodate that condition.
>
> Keep in mind that about 100,000 S.E. aircraft are
> flying around out there now with one altenrator, one
> battery and the same risk for loss of system due to
> battery coming unhooked. It's much more likely that
> you'll get alternator or contactor failure than
> failure of wires on the battery. So an all-electric-
> on-a-budget architecture is waaaaayyyyyy more reliable
> than anything flying around in spam-can-land.
>
> Consider too that for most of the way we use our
> airplanes, TOTAL loss of electrical system can be
> tolerated. I normally use hand-held GPS to navigate
> and I carry a hand-held VOR/COM. When I walk up to
> a rental airplane, there's no practical way for me
> to assess the condition or history of that ship's
> electrical system. If I can fly a J-3 somewhere
> with no electrical system, I can fly an A-36
> too.
>
> Bob . . .
>
Yes I agree 100%. This system is an order of magnitude more reliable than
the one that is installed in most of the factory ships, but they have analog
instruments and that vacuum system so they know how fast they are going and
which end is up without the electrical system. I won't, so I demand a
little higher reliablity. That being said my plane will begin life as a VFR
only ship and losing every instrument on the panel shouldn't cause me much
grief, so this system will work GREAT. When I decide to go IFR or replace
the other mag with an electronic ignition then I'll have to decide whether I
need some more comfort factor.
Bob, Thanks for your contribution to our hobby. I have learned a lot from
your book and this list.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
________________________________________________________________________________
| From: | "Werner Schneider" <wernerschneider(at)compuserve.com> |
| Subject: | Re: Feedback on the active noise headset conversion |
A friend of mine did and he is exited about the result, he had nobrand
headsets and
a lout OneDesign and the result is realy surprising good. And think he paid
around 200$
per kit and his brother did the wiring.
I can give you his email so you can have more details.
Werner
----- Original Message -----
From: "Ian Scott" <jabiru22(at)yahoo.com.au>
Subject: AeroElectric-List: Feedback on the active noise headset conversion
>
>
> I was wondering if anyone had upgraded their normal headsets to active
> noise reduction and what the results where like? I.e. the kit that
> replaces the innards for your old headset.
>
> Prices a paid & results and so on?
>
> Thanks
>
> Ian
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | The value talking about simple-ideas . . . |
>
>Bob, Thanks for your contribution to our hobby. I have learned a lot from
>your book and this list.
>
>Godspeed,
>
>Phil Birkelbach - Houston Texas
>RV-7 N727WB (Reserved) - Fuselage
>http://www.myrv7.com
I've learned more about aircraft electrical system
engineering and architecture working in the OBAM
community for the past 16 years than I did working
in the certified community in 25 years before.
It all has to do with identifying simple-ideas
and refining a search for more. Everyone
puts their heads together to see how the pieces
can go together in more useful ways. This is VERY
difficult if not almost impossible to do in the
certified factory environment spread out over
a square mile.
As a matter of fact, I'm presently tasked with
figuring out a way to optimize the exchange of
knowledge within RAC engineering community.
The classic image of how this might be accomplished
is to organize and conduct a bunch of meetings.
Dee and I are hitting the asphalt tonight driving
to Denver for our next weekend seminar. I'll
be copilot with the lap-top. I'm crafting a white
paper that trades off the differences between
classic formal education versus the informal
exchange of ideas.
I will rely heavily on my experience with the
OBAM community to see if I can sell RAC management
on a "new" concept in sharing of simple-ideas
and lessons-learned with guess what? . . .
a LIST SERVER.
At least one thing is different than past
attempts to improve engineering excellence
in an institutionalize environment. I have
an OVERHEAD work order to which participants
can charge their participation time. In the
past, this would be frowned upon by
program managers that perceive the activity
as idle chit-chat which puts pressure
on their project budgets.
This isn't the first time the problem has
been pondered and it won't be the last. This is
a case where the OBAM community has something
to teach the "experts"! I am hopeful.
Bob . . .
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
| Subject: | RE: non-Microprocessor based Fuel Gauge Linearizer |
>What about calibrating the analogue gauge in a non-linear fashion?
>Low parts count, nothing to fail.
>Perfectly calibrated and only costs the replacement face in a gauge. (or
>a bit of paper).
>Ian
Ian Scott is right of course, but lots of people want something fancier.
However, it suggests that a
gauge where the linearizer is inside the gauge is a pretty cool idea.
This is not so easy to do if you already have the gauges installed,
but it reaffirms my plans to use those 10-led bar graphs.
The turn-on-quantity of each led can be set very accurately
and even 1/2 an led can be read. One more steam gauge bites the dust.
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones(at)charter.net
"Nothing is too wonderful to be true."
- James Clerk Maxwell, discoverer of electromagnetism
"Too much of a good thing can be wonderful."
- Mae West, discoverer of personal magnetism
________________________________________________________________________________
| Subject: | Re: Feedback on the active noise headset conversion |
| From: | Joel Harding <cajole76(at)ispwest.com> |
Ian,
Aviation Consumer had an evaluation of the Headsets Inc. conversion
awhile back ( May 2000 and December 2000) and they compared very well
with the Lightspeeds and DREs.
Joel Harding
On Thursday, May 15, 2003, at 07:21 AM, Ian Scott wrote:
>
>
>
> I was wondering if anyone had upgraded their normal headsets to active
> noise reduction and what the results where like? I.e. the kit that
> replaces the innards for your old headset.
>
> Prices a paid & results and so on?
>
> Thanks
>
> Ian
>
>
> _-
> ======================================================================
> _-
> ======================================================================
> _-
> ======================================================================
> _-
> ======================================================================
>
>
________________________________________________________________________________
| From: | John Loram <johnl(at)loram.org> |
| Subject: | AutoPilot Disconnect |
Thanks, Bob. Not bad for a music major!
I have your book and keep it up to date. Wouldn't be without it. The reward
was in the adventure.
And thank you for always being there with a helping hand.
regards, -john-
john(at)loram.org
www.loram.org
-----Original Message-----
From: Robert L. Nuckolls, III [mailto:bob.nuckolls(at)cox.net]
Subject: RE: AeroElectric-List: AutoPilot Disconnect
>
>This analysis makes some simplifying assumptions; most importantly that the
>switch and relay contacts have zero resistance, and that the only
non-purely
>resistive component is the relay coil. The calculation of the effect of
>these tertiary elements are left to the student.... ;-)
>
>
> >(is there a prize????) ;-) -john-
>
> Sure, after you finish the test . . .
>
> Bob . . .
You got it. Do you have a copy of the CD we
sell?
Bob . . .
________________________________________________________________________________
| From: | "John Karnes" <jpkarnes(at)charter.net> |
| Subject: | Re: OV circuit breaker tripping |
> Hmmm . . . perhaps there's a short inside the contactor.
> I've heard of such things but never seen them. Disconnect
> all the wires from the small terminals of the contactor
> and measure the resistance between the two terminals and then
> from each terminal to the contactor case and tell us what you
> find.
>
> Bob . . .
Well...
The reading between the two small posts was 15 ohms. Between all other
posts (big to small, big to big) was "infinite" ohms. Same goes for post to
case. What should the reading be over the 80 amp fuse? I show some
resistance over the fuse... Thanks again for all your help.
John Karnes
Port Orchard, WA
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: LOM OVP System |
>
>
>Hello Bob,
>
>So looking at your drawing Z-18 raises a question of what I wood be
>interested in your opinion:
>
>Would it be ok related to the failure scenarios of a mechanical regulator to
>only use the GENERATOR FIELD DISCONNECT RELAY to cut the field in an
>OVP-event and to rely on the reverse current cuttoff relay consisted in the
>regulator to disconnect the D+ line from the B+ line due to the resulting
>breakdown of the generator output?
I guess it depends on the failure mode. Not having intimate
details on the construction of the regulator, I cannot
deduce failure modes and behavior in modes unique to
that product.
>Do you have experience with this LUN regulator?
No.
>I have studied the little scematic in the cap and came to the opinion that
>it is a 3 point type (cutout, voltage and current) where 2 contacts( cutout
>and current) are located on one coil core.
Interesting . . . I'm having trouble figuring out how that works. Normally
a current limit contactor closes on decrease of magnetic field while a
cutout contact closes on increase of magnetic field. I can sorta see
how you might be clever and design both current and voltage limits
onto the same coil reverse current on the other . . .
>I have to admit that I do not fully understand the functionality of the PR
>pin. It seems to me to be a potential paralleling in/output for a
>2-Generator system.
That's HAS been done so your suggestion is not unreasonable
>Nevertheless I have meassured that it is normally open and if the cutout
>relay is connecting the generator voltage shows up there after passing a
>coil on the voltage relay.
>If one knew the effects on the voltage regulation( so to avoid influance
>there) it would be a positive possible indication for generator operation
>because it shows the state of the cutout relay.
The most common failure I've seen in electro-mechanical regulators
to create and ov condition is broken wire on the voltage control
coil. Of course, breaking the field lead will mitigate the ov
condition. My reasoning for opening this one lead was that should
the reverse current cutout be stuck shut as well, the upstream
protection (fusible link, breaker or fuse) would open due to high
value of current flowing back into the generator.
One could make the ov relay a two-pole device to open BOTH
field and output leads . . . be sure to do BOTH. If you open
only the output lead, the ov condition will continue on the
generator and it will happily commit suicide by burning up
it's own field windings.
You could also consider a faster acting output protection like
a fuse . . . it can be pretty large compared to generator output
'cause the overload will be severe if the field lead is opended
and the reverse current relay in the regulator doesn't react
properly.
Welcome to the Aero-Electric List. Hope you'll hang around
an participate in some really cool discussions.
Bob . . .
________________________________________________________________________________
| From: | cary rhodes <rhodeseng(at)yahoo.com> |
| Subject: | RE: Feedback on the active noise headset conversion |
I converted my DC's a couple years ago w/ the Headsets
Inc kit.
It works well. My only complaint is the battery
consumption.
And I guess the additional wire to tangle w/
everything else.
Seems that the 9V is always used up.
It needs a motion detector to turn itslf off from
nonuse
cary
__________________________________
http://search.yahoo.com
________________________________________________________________________________
| From: | "Jim Pack" <jpack(at)igs3.com> |
| Subject: | Pitch Trim Limit Switches |
How important are the limit switches for electric trim? I'm using a
matronics governor with the standard Van's pitch rim servos on a 9A. I'm
considering not using limit switches. What are the drawbacks of this
decision?
- Jim
________________________________________________________________________________
| Subject: | Re: Flap system failure modes (Was circuit protection |
issues)
Bob,
It's nice to get so much information. Thanks a lot.
> Hmmmm . . . Without specific measurements on your
> group of 4 motors, I'm reluctant to offer an
> opinion. With the right gear ratio, ONE of those
> motors will run the flaps. In fact, the actuator
> popular with RV builders uses a ball-screw that
> is so efficient that a motor about the same size
> runs the flaps with very little current compared
> to ANYTHING with worm or acme drive components.
Ball screws. That's it. The standard equipment includes special drive screws
and what seems to be bronze nuts driving the flaps.
If it were my airplane I'd go for chain driven ball screws, and a single
motor. Indeed those worm gears do SOUND like there is a lot of friction. By
the way what is an acme drive ?
....................
>
> Let's go the 20A fuse. This will be easy to test
> before you fly. Run flaps to mid position. Then
> do a series of flap drive operations for just a
> second or so each direction. Delay long enough
> between pulses to let the motors come to a stop.
> If the fuse stays in place with a couple dozen
> short term reversals over a period of a minute
> or so, then it's going to be okay with respect
> to in-flight operations.
>
> Once the ground test is complete, we can go after
> the flight data to see if we have a justification
> for scaling the fuse to any lower value.
Wilco.
Thanks you,
Gilles
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: Pitch Trim Limit Switches |
What limit switches? I didn't know there were any.
Godspeed,
Phil Birkelbach - Houston
RV7 - 727WB (Reserved)
----- Original Message -----
From: "Jim Pack" <jpack(at)igs3.com>
Subject: AeroElectric-List: Pitch Trim Limit Switches
>
> How important are the limit switches for electric trim? I'm using a
> matronics governor with the standard Van's pitch rim servos on a 9A. I'm
> considering not using limit switches. What are the drawbacks of this
> decision?
>
> - Jim
>
>
>
>
>
>
________________________________________________________________________________
| Subject: | Re: Diode failures and "Reliable Systems" |
Hello David,
A diode is one of the most long term reliable electronic components used in
electronics today. Properly used in a circuit (correct peak inverse voltage
and forward current ratings are a must) a diode should last virtually
forever.
If stressed beyond it's capability, any component in your aircraft can fail.
Don't just pick on diodes. The key is to choose a diode that will do the job
with a margin of safety and forget it. Do you stay up at night worrying
about the reliability of fuses because one blew in your aircraft? You fix
the cause of the over current that occurred and replace the fuse.
I am sure Bob will hammer on the keys for a while about this. Yes, in some
applications a diode failure can be catastrophic to the rest of the circuit
it is used in, but so could many other components make some smoke if failure
were to occur.
A diode used to isolate the E-bus from the main bus could fail shorted if
stressed beyond it's current capability and it could also fail open. A
properly sized fuse in series with the diode will protect it from both
failure modes but that fuse will impact kiss and total system reliability
just to save a $1 part. I would not worry about the E-bus diode any more
than I would worry about the wire that feeds the E-bus. Pick a diode that
approaches the feed wire's performance and you have it solved.
John P. Marzluf
Columbus, Ohio
Kitfox Outback (out back in the garage)
________________________________________________________________________________
| From: | "Jim Pack" <jpack(at)igs3.com> |
| Subject: | Pitch Trim Limit Switches |
The switches are not in the Van's kit, but in the AeroElectric diagrams.
> What limit switches? I didn't know there were any.
>
> Godspeed,
>
> Phil Birkelbach - Houston
> RV7 - 727WB (Reserved)
>
> ----- Original Message -----
> From: "Jim Pack" <jpack(at)igs3.com>
> To:
> Subject: AeroElectric-List: Pitch Trim Limit Switches
>
>
> >
> > How important are the limit switches for electric trim? I'm using a
> > matronics governor with the standard Van's pitch rim servos on a 9A.
I'm
> > considering not using limit switches. What are the drawbacks of this
> > decision?
> >
> > - Jim
________________________________________________________________________________
| Subject: | Re: Flap system failure modes (Was circuit protection |
issues)
Threaded fasteners (screws, bolts, etc.) have a "V" thread, which is
relatively easy to machine and roll, but is a poor choice for power
transmission. A "V" thread has an angle of 60 degrees between opposing
faces, while the Acme is only 29 degrees and is also flat on the peaks and
valleys. The Acme thread is more efficient, with less friction, which in
turn means less wear and longer life. The Acme thread is usually used for
converting from rotary to linear motion. For an example close to home,
examine the screw in any bench vice.
Best regards,
Rob Housman
Europa XS Tri-Gear A070
Airfarame complete
Irvine, CA
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
Gilles.Thesee
Subject: Re: AeroElectric-List: Re: Flap system failure modes (Was circuit
protection issues)
<Gilles.Thesee@ac-grenoble.fr>
SNIP
By the way what is an acme drive ?
SNIP
Thanks you,
Gilles
________________________________________________________________________________
| From: | "Bartrim, Todd" <sbartrim(at)mail.canfor.ca> |
Hi Bob;
I'd like to build a crowbar OVM, using your design. The schematic
and BOM on your site call for a diac, part #MBS4991. This is an invalid
Digi-Key #. In the archives I found an e-mail of yours from back in 2001,
indicating that this part is now obsolete and that you were going to rework
the design.
I've found another design at
www.aeroelectric.com/articles/crowbar.pdf that has a revision date of
4/16/2. This design has a higher parts count but they are all available from
Digi-Key (except 3292w501 but I assume I can substitute 3352E-501-ND).
Is this the latest revision?
Thanks
S. Todd Bartrim
Turbo 13B rotary powered
RX-9endurance
C-FSTB
http://www3.telus.net/haywire/RV-9/C-FSTB.htm
"Imagination is more important than knowledge"
-Albert Einstein
OVM parts list
Hi Bob;
I'd like to build a crowbar OVM, using your design. The schematic and BOM on your
site call for a diac, part #MBS4991. This is an invalid Digi-Key #. In the
archives I found an e-mail of yours from back in 2001, indicating that this part
is now obsolete and that you were going to rework the design.
I've found another design at www.aeroelectric.com/articles/crowbar.pdf that has a revision date of 4/16/2. This design has a higher parts count but they are all available from Digi-Key (except 3292w501 but I assume I can substitute 3352E-501-ND).
Is this the latest revision?
Thanks
S. Todd Bartrim
Turbo 13B rotary powered
RX-9endurance
C-FSTB
http://www3.telus.net/haywire/RV-9/C-FSTB.htm
Imagination is more important than knowledge
-Albert Einstein
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: OVM parts list |
>
>
>Hi Bob;
> I'd like to build a crowbar OVM, using your design. The schematic
>and BOM on your site call for a diac, part #MBS4991. This is an invalid
>Digi-Key #. In the archives I found an e-mail of yours from back in 2001,
>indicating that this part is now obsolete and that you were going to rework
>the design.
> I've found another design at
>www.aeroelectric.com/articles/crowbar.pdf that has a revision date of
>4/16/2. This design has a higher parts count but they are all available from
>Digi-Key (except 3292w501 but I assume I can substitute 3352E-501-ND).
Yup. That's the latest. Any 500 ohm, linear pot will
work.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Pitch Trim Limit Switches |
>
>How important are the limit switches for electric trim? I'm using a
>matronics governor with the standard Van's pitch rim servos on a 9A. I'm
>considering not using limit switches. What are the drawbacks of this
>decision?
Limit switches are used to stop the motor at or
just before the mechanism's travel reaches a hard
limit. This prevents the mechanism from banging
the stops and binding/breaking something and/or
burning out a motor.
It depends on the design. Van's flap actuator has
ball screw followers that free wheel when they reach
mechanical limits of the screw . . . if you design
you system to use exactly the stroke of this screw,
then no limit switches are needed.
Don't know the details of the trim system. Some
folks need limit switches, others don't.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Flap system failure modes |
><Gilles.Thesee@ac-grenoble.fr>
>
>
>Bob,
>
>It's nice to get so much information. Thanks a lot.
>
> > Hmmmm . . . Without specific measurements on your
> > group of 4 motors, I'm reluctant to offer an
> > opinion. With the right gear ratio, ONE of those
> > motors will run the flaps. In fact, the actuator
> > popular with RV builders uses a ball-screw that
> > is so efficient that a motor about the same size
> > runs the flaps with very little current compared
> > to ANYTHING with worm or acme drive components.
>
>Ball screws. That's it. The standard equipment includes special drive screws
>and what seems to be bronze nuts driving the flaps.
>If it were my airplane I'd go for chain driven ball screws, and a single
>motor. Indeed those worm gears do SOUND like there is a lot of friction. By
>the way what is an acme drive ?
Acme threads are square cut . . . someone else mentioned
they're commonly used on bench vises. The lead screw on
my lathe is an acme thread screw. Very high friction (hence
your vise stays tight after you cinch things down).
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: OV circuit breaker tripping |
>
>
> > Hmmm . . . perhaps there's a short inside the contactor.
> > I've heard of such things but never seen them. Disconnect
> > all the wires from the small terminals of the contactor
> > and measure the resistance between the two terminals and then
> > from each terminal to the contactor case and tell us what you
> > find.
> >
> > Bob . . .
>
>Well...
>The reading between the two small posts was 15 ohms. Between all other
>posts (big to small, big to big) was "infinite" ohms. Same goes for post to
>case. What should the reading be over the 80 amp fuse? I show some
>resistance over the fuse... Thanks again for all your help.
The 80A fuse has nothing to do with the power path
through the master switch, control breaker, contactor
coil, ovm and finally to the control lead of your alternator.
The overload exists somewhere along that path and/or
involves one of those components.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Diode failures and "Reliable Systems" |
>
>A diode used to isolate the E-bus from the main bus could fail shorted if
>stressed beyond it's current capability and it could also fail open. A
>properly sized fuse in series with the diode will protect it from both
>failure modes but that fuse will impact kiss and total system reliability
>just to save a $1 part. I would not worry about the E-bus diode any more
>than I would worry about the wire that feeds the E-bus. Pick a diode that
>approaches the feed wire's performance and you have it solved.
Our favorite diode was selected because it comes in
an easy to mount package with 1/4" fast-on terminals
thus easy to wire too. It's so electrically oversized to
the task as to approach absurdity but since the "oversized"
part is so cheap that it seemed more practical to use
it because of ease of use as opposed to any electrical
considerations.
Bob . . .
________________________________________________________________________________
| From: | "William Slaughter" <willslau(at)alumni.rice.edu> |
| Subject: | Feedback on the active noise headset conversion |
I recently had a pair of David Clarks converted by Headsets, Inc. and am
very pleased with the result. I shipped mine in for conversion at their
facility, but they have a kit for do-it-yourself. You can check all of the
options and prices on their website at www.headsetsinc.com
Highly recommended.
William Slaughter
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Ian
Scott
Subject: AeroElectric-List: Feedback on the active noise headset
conversion
I was wondering if anyone had upgraded their normal headsets to active
noise reduction and what the results where like? I.e. the kit that
replaces the innards for your old headset.
Prices a paid & results and so on?
Thanks
Ian
________________________________________________________________________________
| From: | RVEIGHTA(at)aol.com |
| Subject: | OV circuit breaker tripping |
John, I have almost exactly the same problem with the ov circuit breaker
tripping. In my case, I missed the callout for a circuit breaker and
installed a 5a fuse, which blew every time I flipped on my master switch. I
have since installed a 5a circuit breaker and it does not trip. However, my
alternator isn't working. Thinking the alternator might be defective, I took
it to an alternator shop and it was pronounced alive and well.
So, today, like you, I bypassed Bob's B lead ov protection contactor, and
viola, I had 14.5v on my voltmeter when I started the Lyc up instead of 12v,
or whatever my poor, unnourished battery could muster. I watched with
anxiety as I put each avionic on line, waiting for wires to glow and smoke to
billow, but it didn't happen. Everything worked as it should.
Just to get another insight on this situation, I emailed Niagara Air Parts,
from whence my alternator came and who, in their installation guide indicate
the B lead should be connected to the battery contactor side of the starter
contactor or directly to the bus. I asked them if I should install crowbars,
ov contactors, et al, and they said they had never had a failure to their
knowledge due to lack of same, but...........
So, where do we go from here? I'm very close to flying this puppy after four
years of construction. I definitely want to fly safely, but I DO want to fly.
By the way; I measured the resistance between the small terminals as Bob
requested of you and I got the same results - 15.4 ohms. Measuring the
terminals to case also resulted in infinity.
Walt Shipley RV8A
Greeneville, TN
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: OV circuit breaker tripping |
>
>John, I have almost exactly the same problem with the ov circuit breaker
>tripping. In my case, I missed the callout for a circuit breaker and
>installed a 5a fuse, which blew every time I flipped on my master switch. I
>have since installed a 5a circuit breaker and it does not trip. However, my
>alternator isn't working. Thinking the alternator might be defective, I took
>it to an alternator shop and it was pronounced alive and well.
>
>So, today, like you, I bypassed Bob's B lead ov protection contactor, and
>viola, I had 14.5v on my voltmeter when I started the Lyc up instead of 12v,
>or whatever my poor, unnourished battery could muster. I watched with
>anxiety as I put each avionic on line, waiting for wires to glow and smoke to
>billow, but it didn't happen. Everything worked as it should.
>
>Just to get another insight on this situation, I emailed Niagara Air Parts,
>from whence my alternator came and who, in their installation guide indicate
>the B lead should be connected to the battery contactor side of the starter
>contactor or directly to the bus. I asked them if I should install crowbars,
>ov contactors, et al, and they said they had never had a failure to their
>knowledge due to lack of same, but...........
Failure rate of modern alternators is indeed rare . . . but not zero.
>So, where do we go from here? I'm very close to flying this puppy after four
>years of construction. I definitely want to fly safely, but I DO want to fly.
When you turn the DC power master switch on all the way
(so that the alternator is ON) with the engine not running,
do you here a "clunk" like that of your battery master contactor?
If you bypass the b-lead disconnect contactor and things work
then you're not getting the b-lead contactor energized. Check
for missing ground lead on the coil. See that little ground symbol
in Z-24 on the upper side of the contactor's coil symbol? That says
you take a wire from there to the firewall ground. Without it, the
contactor doesn't pull in and you don't get the alternator on line.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Off-line for a few days . . . |
Dee and I are headed for Denver about o-dark-thirty
in the morning. Join us in Englewood if you can. See:
http://www.aeroelectric.com/seminars/Englewood.html
. . . but otherwise, see you all Monday.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Tom..." <tsled(at)pacbell.net> |
| Subject: | Feedback on the active noise headset conversion |
Hiya Gents,
about two years ago I was flying a gyro with a Subaru engine just a few feet
behind my head. I was using my old Army helicopter helmet and the engine
was way too loud. I sent it in to this same place (it was much smaller
then, the owner was/is a Brazilia pilot) they did a fantastic job! I could
star the engine, taxi out, go to full revs, click on the AN and just hear a
small hum of the engine in the background. Sweet....!
Tom...
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
William Slaughter
Subject: RE: AeroElectric-List: Feedback on the active noise headset
conversion
I recently had a pair of David Clarks converted by Headsets, Inc. and am
very pleased with the result. I shipped mine in for conversion at their
facility, but they have a kit for do-it-yourself. You can check all of the
options and prices on their website at www.headsetsinc.com
Highly recommended.
William Slaughter
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Ian
Scott
Subject: AeroElectric-List: Feedback on the active noise headset
conversion
I was wondering if anyone had upgraded their normal headsets to active
noise reduction and what the results where like? I.e. the kit that
replaces the innards for your old headset.
Prices a paid & results and so on?
Thanks
Ian
________________________________________________________________________________
| From: | "John Karnes" <jpkarnes(at)charter.net> |
| Subject: | Re: OV circuit breaker tripping |
> So, where do we go from here? I'm very close to flying this puppy after
four
> years of construction. I definitely want to fly safely, but I DO want to
fly.
> Walt Shipley RV8A
> Greeneville, TN
You know, I'm not sure of the need for the B-lead contactor. For what
purpose does it serve? Some of the earlier aeroelectric schematics shows
the B-lead going to the starter contactor, just like we tried. What is the
harm of just putting the 80 amp fuse between the alternator and the starter
contactor and go from there?
John Karnes
Port Orchard, WA
________________________________________________________________________________
| From: | "Ida Covey" <ICOVEY(at)nc.rr.com> |
| Subject: | Source of Acme drives |
Does anyone know of a source of small Acme drives? I'm looking for
something to be manually operated with an operating range of 1.5 to 2
inches, about 3/16 or 1/4 inch diameter. I plan to use it to load a spring
for a manual rudder trim in a Glasair.
Thanks,
BJC
________________________________________________________________________________
| From: | "Gary Casey" <glcasey(at)adelphia.net> |
| Subject: | redundant electrical systems |
Anyone know what type of electrical system was on the Voyager? Just curious
how they handled the redundancy question.
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: redundant electrical systems |
In a message dated 5/16/03 7:17:36 AM Central Daylight Time,
glcasey(at)adelphia.net writes:
> Anyone know what type of electrical system was on the Voyager? Just curious
> how they handled the redundancy question.
>
Good Morning Gary,
I don't know anything about the Voyager, but it has been said that the very
first Twin Beeches (Model 18) had two entirely separate electrical systems.
One for each engine. I have never seen one in that configuration. Most were
converted to a balanced system along the way. I was told that each side had
it's own twelve volt battery in the wing near the nacelle. Some of the
electrical components had single pole, double throw, center off switches.
The pilot could select which system would supply the equipment. Others were
only connected to one side or the other. For a twin, that has possibilities!
Happy Skies,
Old Bob
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: Source of Acme drives |
Don't know of an 'Acme drive' that small, but the Ray Allen servos would
probalby fit the bill and they are designed specifically to be trim servos.
They may not have quite the travel that you are looking for but the are
torquey little beasts and you could rig a small lever mechanism. This is
the way the aileron trim is done on the RV's.
Here is a picture of the aileron trim servo installation in my RV-7. I
don't know if you can tell exactly how it works from the photo but it may
help...
http://www.myrv7.com/viewimage.php?pictureid=247
Here is a link to Ray Allen Company...
http://www.rayallencompany.com/
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
----- Original Message -----
From: "Ida Covey" <ICOVEY(at)nc.rr.com>
Subject: AeroElectric-List: Source of Acme drives
>
> Does anyone know of a source of small Acme drives? I'm looking for
> something to be manually operated with an operating range of 1.5 to 2
> inches, about 3/16 or 1/4 inch diameter. I plan to use it to load a
spring
> for a manual rudder trim in a Glasair.
>
> Thanks,
>
> BJC
>
>
________________________________________________________________________________
| Subject: | Re: Feedback on the active noise headset |
conversion
| From: | Denis Walsh <denis.walsh(at)attbi.com> |
>
> Hiya Gents,
>
> about two years ago I was flying a gyro with a Subaru engine just a few feet
> behind my head. I was using my old Army helicopter helmet and the engine
> was way too loud. I sent it in to this same place (it was much smaller
> then, the owner was/is a Brazilia pilot) they did a fantastic job! I could
> star the engine, taxi out, go to full revs, click on the AN and just hear a
> small hum of the engine in the background. Sweet....!
>
> Tom...
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of
> William Slaughter
> To: aeroelectric-list(at)matronics.com
> Subject: RE: AeroElectric-List: Feedback on the active noise headset
> conversion
>
>
>
> I recently had a pair of David Clarks converted by Headsets, Inc. and am
> very pleased with the result. I shipped mine in for conversion at their
> facility, but they have a kit for do-it-yourself. You can check all of the
> options and prices on their website at www.headsetsinc.com
> Highly recommended.
>
> William Slaughter
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Ian
> Scott
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Feedback on the active noise headset
> conversion
>
>
> I was wondering if anyone had upgraded their normal headsets to active
> noise reduction and what the results where like? I.e. the kit that
> replaces the innards for your old headset.
>
> Prices a paid & results and so on?
>
> Thanks
>
> Ian
>
Done it twice. Peltors. Works good last long. The second one showed some
improvements. Good company. Need a soldering iron, and bout $200. A
little less for other brands. The ANR performance is at least as good as
the others.
If you have a headset you really like, it is the way to go. If you are
starting from scratch it is a tougher choice to make.
Denis
________________________________________________________________________________
| From: | William Mills <courierboy(at)earthlink.net> |
| Subject: | Voyager electrics |
>
>Anyone know what type of electrical system was on the Voyager? Just curious
>how they handled the redundancy question.
Don't know if Bob designed the system/s but I think it had B and C
alternators/PMGs, and regulators.
He has mentioned it here, but only briefly if I recall. Bet he could
tell us lots about that plane.
Bill
________________________________________________________________________________
| From: | "David Burton" <dburton(at)nwlink.com> |
| Subject: | Re: Source of Acme drives |
Take a look at "Small Parts". It is a great resource. We purchase a lot of
items from them. Prices are not great, but if you only need a few of
something they sell in small quantities. I purchase stuff from them often
for a project because I can find everything I need at one place.
http://www.smallparts.com/
________________________________________________________________________________
| From: | "David Swartzendruber" <dswartzendruber(at)earthlink.net> |
| Subject: | Voyager electrics |
Bob designed the regulators that were used on the Voyager, the LR-1's.
This was the predecessor to the LR-3 that B&C now sells. The
alternators were not original B&C designs. I believe that B&C procured
some OEM type alternators from AeroElectric in Wichita, (now a Kelly
Aerospace division called Turbine Rotables, no connection with Bob's
AeroElectric name), and performed some type of modification to them. I
have no idea how the power distribution system was configured on the
Voyager, Bob probably does.
Dave in Wichita
> >
> >Anyone know what type of electrical system was on the Voyager? Just
> curious
> >how they handled the redundancy question.
>
>
> Don't know if Bob designed the system/s but I think it had B and C
> alternators/PMGs, and regulators.
>
> He has mentioned it here, but only briefly if I recall. Bet he could
> tell us lots about that plane.
>
> Bill
>
________________________________________________________________________________
| From: | "Dan Morrow" <DanFM01(at)butter.toast.net> |
| Subject: | Avogadro's Number |
The National Institute of Technology and Standards (formerly known as the
Bureau of Standards) gives this value for Avogadro's number:
Avogadro constant 6.022 141 99 x 10E23
Standard uncertainty 0.000 000 47 x 10E23
See
http://www.physics.nist.gov/cgi-bin/cuu/Results?search_for=avogadro%27s+numb
er
Since this is the government speaking, that must be right, huh? Actually,
the NIST site, http://www.nist.gov/ is a good source for conversions factors
and constants of all sorts.
Dan Morrow
RV8A Building Empennage slowly
________________________________________________________________________________
| Subject: | Re: Voyager electrics |
> > >
> > >Anyone know what type of electrical system was on the Voyager? Just
> > curious
> > >how they handled the redundancy question.
> >
> >
> > Don't know if Bob designed the system/s but I think it had B and C
> > alternators/PMGs, and regulators.
> >
> > He has mentioned it here, but only briefly if I recall. Bet he could
> > tell us lots about that plane.
> >
> > Bill
> >
>
Hi all,
I believe Jim Weir also esigned some antennas and maybe some parts of the
electrical system too.
Gilles
________________________________________________________________________________
| From: | RVEIGHTA(at)aol.com |
| Subject: | Re: OV circuit breaker tripping |
Bob, yep, I get the "clunk" when I turn on the master. I also checked my
installation and the ground wire to the firewall is there, so that's not the
problem.
Walt
________________________________________________________________________________
| From: | "royt.or" <royt.or(at)netzero.net> |
| Subject: | Re: Cheap blind encoder. |
Another encoder option to consider, especially with GNS430 is the
microEncoder
from Rocky Mountain Instruments. http://www.rkymtn.com/. At $879 for the kit
version, it is not cheap as encoders go, but it is inexpensive for the added
capabilities it enables in the GNS430. In addition to being an encoder, the
microEncoder displays and can supply the GPS with altimeter setting,
airspeed, vertical speed, OAT, and with the optional $250 compass module,
the magnetic heading. Not having to enter this information manually into the
GPS sure seems like it will reduce pilot workload. I just completed my 3rd
flight on my (over equipped?) plane and it was cool to have the wind vector
arrow in the GNS430. The Air Data computers reviewed in May '03 The Aviation
Consumer cost ~$3000 to provide this information. Granted the $3K air data
computers supply fuel flow/capacity information also. Too bad the fuel
totalizer in my EIS does not output information for the GPS also.
My panel was built by Pacific Coast avionics. I'm using a Garmin GTX327
transponder. I'm not certain which communication interface goes between the
units, but I don't believe there were any diodes included. I can get more
details if needed.
One other Garmin feature: I have my GNS430 linked to my portable GPSMAP 295,
so that the flight plan in the GNS430 is automatically loaded into the
GPSMAP 295. That way if I lose my GNS430 for some reason, my GPSMAP 295 has
my flight plan. If the GPSMAP 295 loses ships power, it switches to it's
internal batteries AND has my flight plan loaded.
Regards,
Roy
(Zenith CH601HDS, nose gear, Rotax 912S, all electric IFR "on a budget".
First flight 5/12/03)
(For quicker email response from me use royDOTthomaATintel.com)
________________________________________________________________________________
| From: | Geoff Evans <hellothaimassage(at)yahoo.com> |
| Subject: | Small aux battery with Z-13 |
Bob (and anyone else with a useful comment):
I'm considering a Z-13 architecture with an additional small (4.5 AH) battery
to support one side of a dual electronic ignition in the very unlikely event
that the main battery goes inop for whatever reason. I perfer this to two
full-sized batteries because it offers unlimited endurance and it weighs
less.
I'm making an assumption here, and that is that a 4.5 AH battery can support
the operation of either the SD-8 or a standard alternator like the L-40. If
this is *not* the case (e.g. I should only use a larger battery with the
larger alternator), then the below-proposed system is overly complicated and
I can slim it down somewhat. I just figured that if I am going to install a
second small battery just incase the main battery goes inop, it might as well
be able to make either of my alternators run as well.
Anyway, I propose connecting the 4.5 AH battery directly to the #2 ignition
with a fuesable link. I will also connect it to the always-hot side of the
main battery contactor through a S704-1 relay. I will call the switch for the
relay the "Aux Battery Bus Tie," and it will be open for starting and closed
for all other operations EXCEPT for when both alternators are inop. In that
case, I'd open the relay to split the batteries so I have more control over
battery endurance.
Additionally, the power to the coil in the relay will come from BOTH
batteries, via diodes. This will allow the relay to be powered from either
battery without allowing current to flow from one battery to the other unless
the relay is actually closed. I think this would be useful in the unlikely
event of a battery-inop situation (which is the only reason I'm installing a
second small battery in the first place). If the aux battery goes inop, I can
still use juice from the main battery to hold the relay closed and thereby
power the #2 ign from the main battery. Alternatively, if the main battery
goes inop, I can use juice from the aux battery to hold the relay closed and
thereby allow the aux battery to be available to support either the L-40 or
the SD-8 alternator.
With this architecture, the only time I'd be without electrical power on the
e-bus and powering only the #2 ign directly from the aux battery is if the
main battery and both alternators died -- highly unlikely.
Once again, I'm making the assumption that a small battery will support
either the SD-8 or the L-40 alternator. I'm also assuming that it's not "bad
practice" or otherwise unadvisable to power a relay from more than one source
via diodes. Please correct these assumptions if they are wrong.
What do you think?
-Geoff
RV-8
__________________________________
http://search.yahoo.com
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
| Subject: | Microprocessor based Fuel Gauge Linearizer |
Neil Hulin's comment about using a fuel totalizer instead of a fuel gauge linearizer
has been burning a hole in my brain. I believe he is right....
Here's the deal--
You only need one fuel totalizer meter if you take fuel from only one tank at a
time. The fuel quantity meter (and memory) for that tank is simply updated as
required. I trust in this system, totalizers really work well.
Consider too, that you wouldn't need fuel-level senders or gauges at all. Always
problematic devices. You also would not need anti-slosh electronic filters
either. My airplane just got a whole lot lighter!
There are a few practical concerns--how do we know the tank is at the level the
"gauge" says it is? Well, I always checked it visually with a wooden stick anyway.
So when tanks are refilled they must be filled to the top (ideally) and
visually checked. You really wanted the fuel flow rate anyway. Not a bad tradeoff.
Eric M. Jones
The whole difference between construction and creation is exactly this:
that a thing constructed can only be loved after it is constructed;
but a thing created is loved before it exists.
- Charles Dickens
________________________________________________________________________________
| From: | Van Caulart <etivc(at)iaw.on.ca> |
| Subject: | Re: Noise canceling headsets |
I was wondering if anyone had upgraded their normal headsets to active
noise reduction and what the results where like? I.e. the kit that
replaces the innards for your old headset.
Prices a paid & results and so on?
I've converted a Dave Clark headset and two others using the kit. They
work great and all three of us wouldn't change back. Highly recommended.
I paid the going rate about $150 US, the DC kit was slightly more. well
documented and good value. Took about 2hrs/set to complete.
PeterVC
________________________________________________________________________________
| From: | "Tom Schiff" <tomschiff(at)attbi.com> |
| Subject: | Microprocessor based Fuel Gauge Linearizer |
The problem is that the FAA requires that there be a fuel gage but only
requires that is shows when the tank is empty. I have been using a fuel
flow in my C-150 for several months. I have been updating the amount
remaining every time I fill by the exact amount that I have filled. It
has been agreeing with the amount determined by sticking the tanks.
After many fills and over 100 gallons of fuel burned it is still within
.2 gallons. So you could probably get away with a fuel gage that is in
reality a fuel flow gage but if you got caught you would be in trouble.
My ideal fuel gage would be several sensors of the type where a led
shines a light through a prism. When the prism is submerged in gas the
light shines on a photo sensor and indicates that the sensor is below
the level of the fuel. The sensors would be at various levels in each
tank an they would light two sets of led indicators on in the cockpit
and another aggacent to the filler port. I this way I would know when I
was about to overfill the tanks. I saw a Money that had a fuel gage next
to the filler port and that is where I got the idea from. Because you
have absolutle freedom where you place the sensors you wouldn't have to
worry about the non linearitys of flat tanks that are inclined at an
angle
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Eric
M. Jones
Subject: AeroElectric-List: Microprocessor based Fuel Gauge Linearizer
Neil Hulin's comment about using a fuel totalizer instead of a fuel
gauge linearizer has been burning a hole in my brain. I believe he is
right....
Here's the deal--
You only need one fuel totalizer meter if you take fuel from only one
tank at a time. The fuel quantity meter (and memory) for that tank is
simply updated as required. I trust in this system, totalizers really
work well.
Consider too, that you wouldn't need fuel-level senders or gauges at
all. Always problematic devices. You also would not need anti-slosh
electronic filters either. My airplane just got a whole lot lighter!
There are a few practical concerns--how do we know the tank is at the
level the "gauge" says it is? Well, I always checked it visually with a
wooden stick anyway. So when tanks are refilled they must be filled to
the top (ideally) and visually checked. You really wanted the fuel flow
rate anyway. Not a bad tradeoff.
Eric M. Jones
The whole difference between construction and creation is exactly this:
that a thing constructed can only be loved after it is constructed;
but a thing created is loved before it exists.
- Charles Dickens
________________________________________________________________________________
| From: | "Wolfgang Trinks" <Wolfgang.Trinks(at)flugbereitschaft.com> |
| Subject: | Re: Microprocessor based Fuel Gauge Linearizer |
I agree that a fuel totalizer in combination with a fuel gauge with a
certain tolerance but precisly showing low fuel situation is a reasonable
way to go.
But there are also others:
I did linearize a the fuel gauge once on my daycruiser(boat). What appeared
to be a weekend programming job on a 80C515 turned into a small >Joint
Strike Fighter< project.
First of all, giving the situation of flat tanks with irregular shapes you
have to determine the funtion of fuel volume versus measuring height of your
sensor at a given sensor position mathematicly using linear algebra. This is
a must.
As this can turn into a nightmare espacially if the tank is inclined during
climb or decent there is a way making things easier(You can neglect bank
because a plane is flown coordinated 99% of the fight time).
Devide your tank in your mind into boxes and put a sensor in the middle of
each box. The smaller the boxes the lower is the influence of the incline
and the more precisly you can determine the volume versus measuring height
by simple trigometrie. The sum of all sensor added one by one will be the
full tank reading where the max value of every sensor equals the
contribution of his box to the total volume. The more boxes, the more
precise and more expensive. So there must be a compromise, but this is
strongly dependent on the shape of the tank.
Anyway when I did this I programmed my f(fuel) in a pascal programm where I
simulated the different incline and was able to play arround with the number
and position of the virtual boxes. It turned out that I could come below 1%
error with 3 sensors on a tank measuring 80cm x 50cm x 180cm in angles up to
15 degree in most unfavourable axis. This was a quite positive experiance. I
think also for a plane with a LL100 grade burning engine 15 degree of
continious pitch up during climb should be far enough.
If you do this you have got the problem on the root and depending on the
type of sensor there will be hardly any linearizing nessecary.
On my boat I used VDO linear resistence floaters and the results where
perfect.
If I would have to do it on a plane today I would use a capacitive system as
sensors because you could very easily build your own sensors (basic
machining required) and finetune the sensors to the tank shape.It also shows
the weight of fuel in the tanks which is the correct measure for your
endurance(ok, this is academic with those tiny volumes).
To get a feeling for all this just look what the big ones are doing if they
need fuel indicators that are serious(Cessna 340,414, King Air, Citation,
all big jets)
Wolfgang...
----- Original Message -----
From: "Tom Schiff" <tomschiff(at)attbi.com>
Subject: RE: AeroElectric-List: Microprocessor based Fuel Gauge Linearizer
>
> The problem is that the FAA requires that there be a fuel gage but only
> requires that is shows when the tank is empty. I have been using a fuel
> flow in my C-150 for several months. I have been updating the amount
> remaining every time I fill by the exact amount that I have filled. It
> has been agreeing with the amount determined by sticking the tanks.
> After many fills and over 100 gallons of fuel burned it is still within
> .2 gallons. So you could probably get away with a fuel gage that is in
> reality a fuel flow gage but if you got caught you would be in trouble.
>
> My ideal fuel gage would be several sensors of the type where a led
> shines a light through a prism. When the prism is submerged in gas the
> light shines on a photo sensor and indicates that the sensor is below
> the level of the fuel. The sensors would be at various levels in each
> tank an they would light two sets of led indicators on in the cockpit
> and another aggacent to the filler port. I this way I would know when I
> was about to overfill the tanks. I saw a Money that had a fuel gage next
> to the filler port and that is where I got the idea from. Because you
> have absolutle freedom where you place the sensors you wouldn't have to
> worry about the non linearitys of flat tanks that are inclined at an
> angle
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Eric
> M. Jones
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Microprocessor based Fuel Gauge Linearizer
>
>
>
> Neil Hulin's comment about using a fuel totalizer instead of a fuel
> gauge linearizer has been burning a hole in my brain. I believe he is
> right....
>
> Here's the deal--
>
> You only need one fuel totalizer meter if you take fuel from only one
> tank at a time. The fuel quantity meter (and memory) for that tank is
> simply updated as required. I trust in this system, totalizers really
> work well.
> Consider too, that you wouldn't need fuel-level senders or gauges at
> all. Always problematic devices. You also would not need anti-slosh
> electronic filters either. My airplane just got a whole lot lighter!
>
> There are a few practical concerns--how do we know the tank is at the
> level the "gauge" says it is? Well, I always checked it visually with a
> wooden stick anyway. So when tanks are refilled they must be filled to
> the top (ideally) and visually checked. You really wanted the fuel flow
> rate anyway. Not a bad tradeoff.
>
> Eric M. Jones
>
> The whole difference between construction and creation is exactly this:
> that a thing constructed can only be loved after it is constructed;
> but a thing created is loved before it exists.
> - Charles Dickens
>
>
________________________________________________________________________________
| From: | "Boyd C. Braem" <bcbraem(at)comcast.net> |
| Subject: | Re: Microprocessor based Fuel Gauge Linearizer |
The fuel flow totalizer (or whatever--Flowscan?, I believe) that talks
to my VM-1000 is consistently within 0.1 gal and has been since 1998. I
could just tape over my analog guages for all the good that they do, I
mean, my watch is better.....
Tom Schiff wrote:
>
>The problem is that the FAA requires that there be a fuel gage but only
>requires that is shows when the tank is empty. I have been using a fuel
>flow in my C-150 for several months. I have been updating the amount
>remaining every time I fill by the exact amount that I have filled. It
>has been agreeing with the amount determined by sticking the tanks.
>After many fills and over 100 gallons of fuel burned it is still within
>.2 gallons. So you could probably get away with a fuel gage that is in
>reality a fuel flow gage but if you got caught you would be in trouble.
>
>My ideal fuel gage would be several sensors of the type where a led
>shines a light through a prism. When the prism is submerged in gas the
>light shines on a photo sensor and indicates that the sensor is below
>the level of the fuel. The sensors would be at various levels in each
>tank an they would light two sets of led indicators on in the cockpit
>and another aggacent to the filler port. I this way I would know when I
>was about to overfill the tanks. I saw a Money that had a fuel gage next
>to the filler port and that is where I got the idea from. Because you
>have absolutle freedom where you place the sensors you wouldn't have to
>worry about the non linearitys of flat tanks that are inclined at an
>angle
>
>-----Original Message-----
>From: owner-aeroelectric-list-server(at)matronics.com
>[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Eric
>M. Jones
>To: aeroelectric-list(at)matronics.com
>Subject: AeroElectric-List: Microprocessor based Fuel Gauge Linearizer
>
>
>
>Neil Hulin's comment about using a fuel totalizer instead of a fuel
>gauge linearizer has been burning a hole in my brain. I believe he is
>right....
>
>Here's the deal--
>
>You only need one fuel totalizer meter if you take fuel from only one
>tank at a time. The fuel quantity meter (and memory) for that tank is
>simply updated as required. I trust in this system, totalizers really
>work well.
>Consider too, that you wouldn't need fuel-level senders or gauges at
>all. Always problematic devices. You also would not need anti-slosh
>electronic filters either. My airplane just got a whole lot lighter!
>
>There are a few practical concerns--how do we know the tank is at the
>level the "gauge" says it is? Well, I always checked it visually with a
>wooden stick anyway. So when tanks are refilled they must be filled to
>the top (ideally) and visually checked. You really wanted the fuel flow
>rate anyway. Not a bad tradeoff.
>
>Eric M. Jones
>
>The whole difference between construction and creation is exactly this:
>that a thing constructed can only be loved after it is constructed;
>but a thing created is loved before it exists.
>- Charles Dickens
>
>
>
>
________________________________________________________________________________
| From: | "Alex Peterson" <alexpeterson(at)usjet.net> |
| Subject: | Microprocessor based Fuel Gauge Linearizer |
>
> The fuel flow totalizer (or whatever--Flowscan?, I believe)
> that talks
> to my VM-1000 is consistently within 0.1 gal and has been
> since 1998. I
> could just tape over my analog guages for all the good that
> they do, I
> mean, my watch is better.....
>
I am using Van's newer style 270 degree arc fuel gauges (I have an
RV6A), together with a totalizer which uses a Floscan transducer. I
find the combination most useful, as the gauges are remarkably accurate
(these indicate gallons in an RV) when in level, reasonably calm air. I
regularly cross check what the gauges indicate for gallonage versus the
totalizer vs time.
Alex Peterson
Maple Grove, MN
RV6-A N66AP 300 hours
www.rvforum.org <| Date: | May 18, 2003 |
| From: | Finn Lassen <finnlassen(at)netzero.net> |
| Subject: | Re: Microprocessor based Fuel Gauge Linearizer |
Here's what I did in my RV-3 tanks.
I made my own capacitive fuel sensors. Two coaxial alu tubes running
from highest point (outboard rib near filler cap) to lowest point (near
drain). In this way there are no "dead" spots.
The senders are 3/16" alu tubing inside thin-walled 1/2" alu tubing.
Separated by nylon spacers at regular intevals (every 6 inches or so).
Nylon spacers cut from thick nylon tubing found at Home Depot, 3/8" OD,
3/16" ID.
You don't want the spacers to be press-fit on both tubes - fuel needs to
pass. I squeezed the inside tube on each side of spacers to hold
spacers in place.
Capacitance varies from approx 109pF (empty) to approx 175 pF (full), if
I remember correctly.
The capacitance to voltage converters is a simply using the capacitance
to control an op-amp set up as an oscillator (capacitance between ground
and - input) , integrating it (R-C filter), rectifying the signal (diode
and capacitor) and amplifying it. The R-C filter needs to be dimensioned
so the frequencies fall on the 6dB/octave slope.
This doesn't product a linear curve, but I feed this into my home-made
engine monitor where I fix that.
Finn
________________________________________________________________________________
| From: | "Fred Stucklen" <wstucklen1(at)cox.net> |
| Subject: | Small aux battery with Z-13 |
Geoff,
What you are proposing should be OK. It's a manual operation , and the small
battery will not actually start the plane, but that's not it's intension.
What I've done on my new RV-6A is install a second 12 Ah battery that couls
be used in a pinch to start the plane. (Like when you've left the master ON all
night......) I've also powered both electronic ignitions from both batteries
via high current (10A) diodes. There are multiple power paths to each ignition:
from the main bus, from each battery via an oil pressure switch (all diode
coupled). Once the engine is started, turning off the MASTER for either/both batteries
does not stop the engine. Furthermore, the AUX (12 Ah) battery will automatically
disconect itself from the bus if the buss voltage drops below a
preset level (via Bob's ABM circuit). This circuit has an OFF-AUTO-ON selector
switch which can be used to force the AUX battery onto the bus. So it becomes
the primary BUSS battery to start the plane... (assumes that you've left the
main battery OFF because it's dead...).....
If you're interested, I can send you AutoCAD compatible schematics....
Fred Stucklen
RV-6A N926RV
Getting ready to Paint!
From: Geoff Evans <hellothaimassage(at)yahoo.com>
Subject: Small aux battery with Z-13
Bob (and anyone else with a useful comment):
I'm considering a Z-13 architecture with an additional small (4.5 AH) battery
to support one side of a dual electronic ignition in the very unlikely event
that the main battery goes inop for whatever reason. I perfer this to two
full-sized batteries because it offers unlimited endurance and it weighs
less.
I'm making an assumption here, and that is that a 4.5 AH battery can support
the operation of either the SD-8 or a standard alternator like the L-40.
If
this is *not* the case (e.g. I should only use a larger battery with the
larger alternator), then the below-proposed system is overly complicated
and
I can slim it down somewhat. I just figured that if I am going to install
a
second small battery just incase the main battery goes inop, it might as
well
be able to make either of my alternators run as well.
Anyway, I propose connecting the 4.5 AH battery directly to the #2 ignition
with a fuesable link. I will also connect it to the always-hot side of the
main battery contactor through a S704-1 relay. I will call the switch for
the
relay the "Aux Battery Bus Tie," and it will be open for starting and closed
for all other operations EXCEPT for when both alternators are inop. In that
case, I'd open the relay to split the batteries so I have more control over
battery endurance.
Additionally, the power to the coil in the relay will come from BOTH
batteries, via diodes. This will allow the relay to be powered from either
battery without allowing current to flow from one battery to the other unless
the relay is actually closed. I think this would be useful in the unlikely
event of a battery-inop situation (which is the only reason I'm installing
a
second small battery in the first place). If the aux battery goes inop, I
can
still use juice from the main battery to hold the relay closed and thereby
power the #2 ign from the main battery. Alternatively, if the main battery
goes inop, I can use juice from the aux battery to hold the relay closed
and
thereby allow the aux battery to be available to support either the L-40
or
the SD-8 alternator.
With this architecture, the only time I'd be without electrical power on
the
e-bus and powering only the #2 ign directly from the aux battery is if the
main battery and both alternators died -- highly unlikely.
Once again, I'm making the assumption that a small battery will support
either the SD-8 or the L-40 alternator. I'm also assuming that it's not "bad
practice" or otherwise unadvisable to power a relay from more than one source
via diodes. Please correct these assumptions if they are wrong.
What do you think?
-Geoff
RV-8
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
| Subject: | RE: (non?) Microprocessor based Fuel Gauge Linearizer |
>>the FAA requires that there be a fuel gage but only
>>requires that is shows when the tank is empty.Tom Schiff
---Tom, could you help steer me in the direction where the FAA requires the fuel
tank empty indicator?
What I am proposing is that using only a totalizer may be the best solution. No
"real" fuel gauges at all. The microprocessor can display fuel remaining without
putting some kind of sensor inside the tank(s). Consider--prior to GPS-- inertial
guidance systems could put a ballistic missile to within 10 meters of
a target on the other side of the world. All this with just time and acceleration
totalizers and some gyros. So displaying a fuel level by totalizing how much
gets removed is simple stuff. And I think some people may be doing it now---
From: http://philip.greenspun.com/flying/diamond-da40
>Fuel Totalizer
>The LCD fuel gauges in N505WT are flashy analog/digital affairs, one for each
side. When the tanks are full, the gauges read 17 >gallons although each tank
in fact holds 20 gallons of usable fuel. As you start to burn below 17 gallons
the gauges come alive. >Compared to the float gauges in old-style planes like
Cessnas the gauges are remarkably consistent and stable. Once you've >burned
down below 3 gallons in a tank, the gauge reads "Lo". There is also a "low fuel"
caution light on the annunciator panel. >Generally the gauges on N505WT are
accurate to within 1 gallon, i.e., if they say that the plane has 20 gallons
remaining the plane >will take a top-off of 20 or 21 gallons.
>Experienced pilots know never to trust fuel gauges. What they want is a fuel totalizer.
The VM1000 incorporates one. If you read >the manual you can learn the
unlabeled button functions necessary to tell the VM1000 "this airplane has
a 40-gallon gas tank" and >"I just filled up the gas tank". From there the VM1000
uses its fuel flow meter to calculate how much fuel is remaining. In 505WT
>this number is consistently off by about 5 percent but in a safe direction:
the VM1000 will show 0 gallons remaining when the plane >is still capable of running
for 20 minutes.
Sounds like that's what Diamond does. So the FAA may not require a cork in the
tank. Anybody know for sure?
Regards,
Eric M. Jones
"Most of the time, he's not as bad all the time, as he is some of the time", said
of Tom Bradley, former mayor of L.A.
________________________________________________________________________________
| Subject: | Re: Small aux battery with Z-13 |
| From: | czechsix(at)juno.com |
Geoff,
If I had decided to stick with Z-13, what you are describing in principle
is what I would have done, only I would have added a 1.3 ah aux battery
instead of 4.5 ah. You can get 1.3 ah batteries with faston terminals
for $10 that weigh 1 lb and best of all, fit in Vans standard battery box
along with the Odyssey (I think the PC 680 if I recall correctly...).
This little guy should be big enough at least to bring the SD-8 online
and that's all you really need, anything more is overkill unless I'm
really missing something obvious??
I've gone a step further in my madness and decided that I'm going to
install a single B&C 40 A alternator and one PC 680 and one of the 1.3ah
aux batts isolated by a Schottky diode a la Klaus Savier's schematic to
feed only one electronic ignition. (I'm running dual lightspeeds). Some
may be quick to point out that Klaus recommends a 4.5 ah aux batt, and
that 1.3 ah is not big enough to outlast my tank of gas. Yes this is
correct, but remember that it only matters if I have catastrophic failure
of my main battery. Using flexible battery leads so as not to break the
terminals off, how likely is this? I've accepted that it's possible, but
the odds of it ever happening even if I fly my RV for 10,000 hours is so
unlikely that the aux battery will probably never be more than dead
weight. Remember, if the alternator fails (which is also unlikely if
Bob's assessment of the reliability of B&C's alternators means anything)
I will still have the 16 ah Odyssey battery, which based on my load
analysis should run one of my ignitions and the rest of my e-bus easily
beyond fuel exhaustion. In this scenario I would probably turn OFF the
ignition running on the aux batt to save it as a last ditch reserve in
case my main batt craps out before I want to land. And if my main
battery dies or fails completely, I need to find a place to land within
30-45 mins to be on the safe side. Yes this would be an inconvenience,
but at this point my entire panel would be completely dark and I would
probably be ready to land, even if it's short of my destination.
Inconvenient perhaps? Yes, but worth the trade-off to me in lieu of
carrying an SD-8 around for the rest of my airplane's life that sets my
back $500, adds several more pounds, and will probably never be used. If
I were going to fly it across the Pacific I'd install the SD-8 in a
heartbeat, but I don't see myself flying this aircraft anywhere here in
the U.S where I'm not within 45 min of a usable runway at any given time.
Any flaws in my logic, feel free to point them out....
--Mark Navratil
Cedar Rapids, Iowa
RV-8A finishing....back to the "KISS" principle so I don't backup the
backup for the backup on my ignition system electrical source...
From: Geoff Evans <hellothaimassage(at)yahoo.com>
Subject: AeroElectric-List: Small aux battery with Z-13
Bob (and anyone else with a useful comment):
I'm considering a Z-13 architecture with an additional small (4.5 AH)
battery
to support one side of a dual electronic ignition in the very unlikely
event
that the main battery goes inop for whatever reason. I perfer this to two
full-sized batteries because it offers unlimited endurance and it weighs
less.
I'm making an assumption here, and that is that a 4.5 AH battery can
support
the operation of either the SD-8 or a standard alternator like the L-40.
If
this is *not* the case (e.g. I should only use a larger battery with the
larger alternator), then the below-proposed system is overly complicated
and
I can slim it down somewhat. I just figured that if I am going to install
a
second small battery just incase the main battery goes inop, it might as
well
be able to make either of my alternators run as well.
Anyway, I propose connecting the 4.5 AH battery directly to the #2
ignition
with a fuesable link. I will also connect it to the always-hot side of
the
main battery contactor through a S704-1 relay. I will call the switch for
the
relay the "Aux Battery Bus Tie," and it will be open for starting and
closed
for all other operations EXCEPT for when both alternators are inop. In
that
case, I'd open the relay to split the batteries so I have more control
over
battery endurance.
Additionally, the power to the coil in the relay will come from BOTH
batteries, via diodes. This will allow the relay to be powered from
either
battery without allowing current to flow from one battery to the other
unless
the relay is actually closed. I think this would be useful in the
unlikely
event of a battery-inop situation (which is the only reason I'm
installing a
second small battery in the first place). If the aux battery goes inop, I
can
still use juice from the main battery to hold the relay closed and
thereby
power the #2 ign from the main battery. Alternatively, if the main
battery
goes inop, I can use juice from the aux battery to hold the relay closed
and
thereby allow the aux battery to be available to support either the L-40
or
the SD-8 alternator.
With this architecture, the only time I'd be without electrical power on
the
e-bus and powering only the #2 ign directly from the aux battery is if
the
main battery and both alternators died -- highly unlikely.
Once again, I'm making the assumption that a small battery will support
either the SD-8 or the L-40 alternator. I'm also assuming that it's not
"bad
practice" or otherwise unadvisable to power a relay from more than one
source
via diodes. Please correct these assumptions if they are wrong.
What do you think?
-Geoff
RV-8
The best thing to hit the internet in years - Juno SpeedBand!
Surf the web up to FIVE TIMES FASTER!
________________________________________________________________________________
| From: | RSwanson <rswan19(at)comcast.net> |
| Subject: | Re: RE: (non?) Microprocessor based Fuel Gauge |
Linearizer
Sec. 23.1337
Powerplant instruments installation.
(a) Instruments and instrument lines.
(1) Each powerplant and auxiliary power unit instrument line must meet the
requirements of Sec. 23.993.
(2) Each line carrying flammable fluids under pressure must--
(i) Have restricting orifices or other safety devices at the source of
pressure to prevent the escape of excessive fluid if the line fails; and
(ii) Be installed and located so that the escape of fluids would not create
a hazard.
(3) Each powerplant and auxiliary power unit instrument that utilizes
flammable fluids must be installed and located so that the escape of fluid
would not create a hazard.
(b) Fuel quantity indicator. There must be a means to indicate to the
flightcrew members the quantity of usable fuel in each tank during flight.
An indicator calibrated in appropriate units and clearly marked to indicate
those units must be used. In addition--
(1) Each fuel quantity indicator must be calibrated to read "zero" during
level flight when the quantity of fuel remaining in the tank is equal to
the unusable fuel supply determined under [Sec. 23.959(a);]
(2) Each exposed sight gauge used as a fuel quantity indicator must be
protected against damage;
(3) Each sight gauge that forms a trap in which water can collect and
freeze must have means to allow drainage on the ground;
(4) There must be a means to indicate the amount of usable fuel in each
tank when the airplane is on the ground (such as by a stick gauge);
(5) Tanks with interconnected outlets and airspaces may be considered as
one tank and need not have separate indicators; and
(6) No fuel quantity indicator is required for an auxiliary tank that is
used only to transfer fuel to other tanks if the relative size of the tank,
the rate of fuel transfer, and operating instructions are adequate to--
(i) Guard against overflow; and
(ii) Give the flight crewmembers prompt warning if transfer is not
proceeding as planned.
(c) Fuel flowmeter system. If a fuel flowmeter system is installed, each
metering component must have a means to by-pass the fuel supply if
malfunctioning of that component severely restricts fuel flow.
----- Original Message -----
From: "Eric M. Jones" <emjones(at)charter.net>
Subject: AeroElectric-List: RE: (non?) Microprocessor based Fuel Gauge
Linearizer
>
> >>the FAA requires that there be a fuel gage but only
> >>requires that is shows when the tank is empty.Tom Schiff
>
> ---Tom, could you help steer me in the direction where the FAA requires
the fuel tank empty indicator?
>
> What I am proposing is that using only a totalizer may be the best
solution. No "real" fuel gauges at all. The microprocessor can display fuel
remaining without putting some kind of sensor inside the tank(s).
Consider--prior to GPS-- inertial guidance systems could put a ballistic
missile to within 10 meters of a target on the other side of the world. All
this with just time and acceleration totalizers and some gyros. So
displaying a fuel level by totalizing how much gets removed is simple
stuff. And I think some people may be doing it now---
>
> From: http://philip.greenspun.com/flying/diamond-da40
> >Fuel Totalizer
> >The LCD fuel gauges in N505WT are flashy analog/digital affairs, one for
each side. When the tanks are full, the gauges read 17 >gallons although
each tank in fact holds 20 gallons of usable fuel. As you start to burn
below 17 gallons the gauges come alive. >Compared to the float gauges in
old-style planes like Cessnas the gauges are remarkably consistent and
stable. Once you've >burned down below 3 gallons in a tank, the gauge reads
"Lo". There is also a "low fuel" caution light on the annunciator panel.
>Generally the gauges on N505WT are accurate to within 1 gallon, i.e., if
they say that the plane has 20 gallons remaining the plane >will take a
top-off of 20 or 21 gallons.
> >Experienced pilots know never to trust fuel gauges. What they want is a
fuel totalizer. The VM1000 incorporates one. If you read >the manual you
can learn the unlabeled button functions necessary to tell the VM1000 "this
airplane has a 40-gallon gas tank" and >"I just filled up the gas tank".
From there the VM1000 uses its fuel flow meter to calculate how much fuel
is remaining. In 505WT >this number is consistently off by about 5 percent
but in a safe direction: the VM1000 will show 0 gallons remaining when the
plane >is still capable of running for 20 minutes.
>
> Sounds like that's what Diamond does. So the FAA may not require a cork
in the tank. Anybody know for sure?
>
> Regards,
>
> Eric M. Jones
>
> "Most of the time, he's not as bad all the time, as he is some of the
time", said of Tom Bradley, former mayor of L.A.
>
>
________________________________________________________________________________
| From: | "Gary Casey" <glcasey(at)adelphia.net> |
<>
I'm wondering why you would want to feed the aux battery from the main
system. The reason I ask is that I'm contemplating a dual batter/dual
alternator system with a small second battery charged by a small alternator
that powers only the second Engine Management System and second fuel pump.
That way it is an independent engine support system not in any way connected
to the "main" system. The second alternator goes away it is time to land,
not an excuse to keep going indefinitely. If I planned to be several hours
away from the nearest airport I might have a different opinion. My theory
now is to keep it as simple as possible and keep the engine running without
human intervention. One likely scenario in your system might be that the
main alternator fails (certainly possible) and you run the main battery down
by mistakenly not shedding enough load. You are about to land and now you
need to operate the landing lights/landing gear/flap motor or whatever, so
you decide to connect the two systems. The large load pulls the second
system down and the engine stops. Keeping the two systems separate
essentially protects the engine from the pilot.
Gary Casey
________________________________________________________________________________
| From: | "Cy Galley" <cgalley(at)qcbc.org> |
| Subject: | Re: RE: (non?) Microprocessor based Fuel Gauge Linearizer |
(1) Each fuel quantity indicator must be calibrated to read "zero" during
level flight when the quantity of fuel remaining in the tank is equal to the
unusable fuel supply determined under 23.959(a);
23.1553 Fuel quantity indicator.
A red radial line must be marked on each indicator at the calibrated zero
reading, as specified in 23.1337(b)(1).
Cy Galley, TC - Chair, Emergency Aircraft Repair, Oshkosh
Editor, EAA Safety Programs
cgalley(at)qcbc.org or experimenter(at)eaa.org
Always looking for articles for the Experimenter
----- Original Message -----
From: "Eric M. Jones" <emjones(at)charter.net>
Subject: AeroElectric-List: RE: (non?) Microprocessor based Fuel Gauge
Linearizer
>
> >>the FAA requires that there be a fuel gage but only
> >>requires that is shows when the tank is empty.Tom Schiff
>
> ---Tom, could you help steer me in the direction where the FAA requires
the fuel tank empty indicator?
>
> What I am proposing is that using only a totalizer may be the best
solution. No "real" fuel gauges at all. The microprocessor can display fuel
remaining without putting some kind of sensor inside the tank(s).
Consider--prior to GPS-- inertial guidance systems could put a ballistic
missile to within 10 meters of a target on the other side of the world. All
this with just time and acceleration totalizers and some gyros. So
displaying a fuel level by totalizing how much gets removed is simple stuff.
And I think some people may be doing it now---
>
> From: http://philip.greenspun.com/flying/diamond-da40
> >Fuel Totalizer
> >The LCD fuel gauges in N505WT are flashy analog/digital affairs, one for
each side. When the tanks are full, the gauges read 17 >gallons although
each tank in fact holds 20 gallons of usable fuel. As you start to burn
below 17 gallons the gauges come alive. >Compared to the float gauges in
old-style planes like Cessnas the gauges are remarkably consistent and
stable. Once you've >burned down below 3 gallons in a tank, the gauge reads
"Lo". There is also a "low fuel" caution light on the annunciator panel.
>Generally the gauges on N505WT are accurate to within 1 gallon, i.e., if
they say that the plane has 20 gallons remaining the plane >will take a
top-off of 20 or 21 gallons.
> >Experienced pilots know never to trust fuel gauges. What they want is a
fuel totalizer. The VM1000 incorporates one. If you read >the manual you can
learn the unlabeled button functions necessary to tell the VM1000 "this
airplane has a 40-gallon gas tank" and >"I just filled up the gas tank".
From there the VM1000 uses its fuel flow meter to calculate how much fuel is
remaining. In 505WT >this number is consistently off by about 5 percent but
in a safe direction: the VM1000 will show 0 gallons remaining when the plane
>is still capable of running for 20 minutes.
>
> Sounds like that's what Diamond does. So the FAA may not require a cork in
the tank. Anybody know for sure?
>
> Regards,
>
> Eric M. Jones
>
> "Most of the time, he's not as bad all the time, as he is some of the
time", said of Tom Bradley, former mayor of L.A.
>
>
________________________________________________________________________________
| From: | "Tom Schiff" <tomschiff(at)attbi.com> |
| Subject: | RE: (non?) Microprocessor based Fuel Gauge Linearizer |
It is part of the minimum instrumentation that is required for VFR
flight for piston aircraft.
Quoting from FAR 91.205(b) it is:
1. Airspeed indicator
2. Altimeter
3. Magnetic direction indicator.
4. Tachometer for each engine.
5. Oil pressure gauge for each engine using pressure system
6. Temperature gauge for each liquid-cooled engine.
7. Oil temperature gauge for each air-cooled engine.
8. Manifold pressure gauge for each altitude engine.
9. Fuel gauge indicating the quantity of fuel in each tank.
10. Landing gear position indicator, if the aircraft as a retractable
landing gear.
There is more to section 91.205(b) but this discussion is about
instrumentation.
True this is for certified aircraft and you could argue that you don't
need it for an Experimental. The question is could you get the inspector
to sign off the finished aircraft without a fuel quantity indicator. I
cannot think of a valid reason not to have one. That said, for me there
is a possibility that I could input the wrong value into the fuel
totalizer at startup and then my fuel quantity would be wrong. In my 150
I depend more on the fuel remaining on the fuel totalizer than the fuel
gages, but I wouldn't have a plane without some form of fuel quantity
indicator. Running out of fuel is too unpleasant an event. When I am
flying at start up I put the time that I must be on the ground based on
my fuel calculations. It is part of my scan to be checking that. I do
this for every flight even a quick three passes around the pattern. So I
am not doing three cross checks of fuel quantity. Gages, fuel flow, and
calculation.
I just attended a seminar where a report was presented of a fuel
starvation accident. The pilot was mature, safety conscious, high time,
instrument rated, hundreds of hours in the accident aircraft. He had a
milk run that he flew on the average of 4 times a month. Point A to
point B on the left tank. Return from point B to point A on the right
tank. The club had installed a Garmin 430 so he decided on the return
flight to shoot some approaches. Fuel calculations showed that he had
the fuel to do it. The totalizer showed he had the fuel. The fuel gages
were working but he had gotten out of the habit of checking them. He ran
out of fuel on the right tank and panicked when the engine stopped. He
ran an absolutely by the book total engine failure procedure including
touchdown. He was slightly injured. The plane was totaled. There was 25
gallons of gas in the left tank. Now if he had been watching the gas
gages this would not have happened.
A few light sensor fuel level indicators are too cheap in relationship
to the cost of an entire aircraft not to include them. At least one per
tank that would warn of less than 1/4 of a tank as is done in some
motorcycles
One thing to notice is that FAR 91.205(b) requires a fuel indicator for
EACH tank. So my 150 has two fuel gages even though the tanks are
plumbed together.
BTW I set up my fuel totalizer so that when it reads zero I am at the
unusable reserve. My gages in the 150 are still (correctly) showing
about 1/8th of a tank.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Eric
M. Jones
Subject: AeroElectric-List: RE: (non?) Microprocessor based Fuel Gauge
Linearizer
>>the FAA requires that there be a fuel gage but only
>>requires that is shows when the tank is empty.Tom Schiff
---Tom, could you help steer me in the direction where the FAA requires
the fuel tank empty indicator?
What I am proposing is that using only a totalizer may be the best
solution. No "real" fuel gauges at all. The microprocessor can display
fuel remaining without putting some kind of sensor inside the tank(s).
Consider--prior to GPS-- inertial guidance systems could put a ballistic
missile to within 10 meters of a target on the other side of the world.
All this with just time and acceleration totalizers and some gyros. So
displaying a fuel level by totalizing how much gets removed is simple
stuff. And I think some people may be doing it now---
From: http://philip.greenspun.com/flying/diamond-da40
>Fuel Totalizer
>The LCD fuel gauges in N505WT are flashy analog/digital affairs, one
for each side. When the tanks are full, the gauges read 17 >gallons
although each tank in fact holds 20 gallons of usable fuel. As you start
to burn below 17 gallons the gauges come alive. >Compared to the float
gauges in old-style planes like Cessnas the gauges are remarkably
consistent and stable. Once you've >burned down below 3 gallons in a
tank, the gauge reads "Lo". There is also a "low fuel" caution light on
the annunciator panel. >Generally the gauges on N505WT are accurate to
within 1 gallon, i.e., if they say that the plane has 20 gallons
remaining the plane >will take a top-off of 20 or 21 gallons.
>Experienced pilots know never to trust fuel gauges. What they want is a
fuel totalizer. The VM1000 incorporates one. If you read >the manual you
can learn the unlabeled button functions necessary to tell the VM1000
"this airplane has a 40-gallon gas tank" and >"I just filled up the gas
tank". From there the VM1000 uses its fuel flow meter to calculate how
much fuel is remaining. In 505WT >this number is consistently off by
about 5 percent but in a safe direction: the VM1000 will show 0 gallons
remaining when the plane >is still capable of running for 20 minutes.
Sounds like that's what Diamond does. So the FAA may not require a cork
in the tank. Anybody know for sure?
Regards,
Eric M. Jones
"Most of the time, he's not as bad all the time, as he is some of the
time", said of Tom Bradley, former mayor of L.A.
________________________________________________________________________________
| From: | Charlie & Tupper England <cengland(at)netdoor.com> |
| Subject: | Re: RE: (non?) Microprocessor based Fuel Gauge |
Linearizer
Eric M. Jones wrote:
>
>
>
>>>the FAA requires that there be a fuel gage but only
>>>requires that is shows when the tank is empty.Tom Schiff
>>>
>>>
>
>---Tom, could you help steer me in the direction where the FAA requires the fuel
tank empty indicator?
>
>What I am proposing is that using only a totalizer may be the best solution. No
"real" fuel gauges at all. The microprocessor can display fuel remaining without
putting some kind of sensor inside the tank(s). Consider--prior to GPS--
inertial guidance systems could put a ballistic missile to within 10 meters of
a target on the other side of the world. All this with just time and acceleration
totalizers and some gyros. So displaying a fuel level by totalizing how much
gets removed is simple stuff. And I think some people may be doing it now---
>
One factor in favor of having an 'empty' indicator in addition to a
totalizer is that the induction system isn't the only way for fuel to
leave a tank. Leaks, forgotten or failed caps, mis-fueling by a line
person, etc can lead to fuel exhaustion that won't be detected by a
totalizer. This might have been the FAA 'logic' in requiring that fuel
indicators accurately indicate 'empty'.
I agree that a totalizer is much more useful than a quantity guage, but
the guage is a good backup for the totalizer.
Charlie
________________________________________________________________________________
| From: | "Tom Schiff" <tomschiff(at)attbi.com> |
| Subject: | Microprocessor based Fuel Gauge Linearizer |
Read the incident that I mention in my other reply.
Also I have read about a few accidents where the fuel drains started
leaking in flight, or where the gas caps were left off, or the wrong dip
stick was used and the initial calculation was wrong.
One of the nice things with a light sensor fuel gage is that the 1/4
full sensor can trigger an audible or visual alarm.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Boyd
C. Braem
Subject: Re: AeroElectric-List: Microprocessor based Fuel Gauge
Linearizer
The fuel flow totalizer (or whatever--Flowscan?, I believe) that talks
to my VM-1000 is consistently within 0.1 gal and has been since 1998. I
could just tape over my analog guages for all the good that they do, I
mean, my watch is better.....
Tom Schiff wrote:
>
>The problem is that the FAA requires that there be a fuel gage but only
>requires that is shows when the tank is empty. I have been using a fuel
>flow in my C-150 for several months. I have been updating the amount
>remaining every time I fill by the exact amount that I have filled. It
>has been agreeing with the amount determined by sticking the tanks.
>After many fills and over 100 gallons of fuel burned it is still within
>.2 gallons. So you could probably get away with a fuel gage that is in
>reality a fuel flow gage but if you got caught you would be in trouble.
>
>My ideal fuel gage would be several sensors of the type where a led
>shines a light through a prism. When the prism is submerged in gas the
>light shines on a photo sensor and indicates that the sensor is below
>the level of the fuel. The sensors would be at various levels in each
>tank an they would light two sets of led indicators on in the cockpit
>and another aggacent to the filler port. I this way I would know when I
>was about to overfill the tanks. I saw a Money that had a fuel gage
next
>to the filler port and that is where I got the idea from. Because you
>have absolutle freedom where you place the sensors you wouldn't have to
>worry about the non linearitys of flat tanks that are inclined at an
>angle
>
>-----Original Message-----
>From: owner-aeroelectric-list-server(at)matronics.com
>[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Eric
>M. Jones
>To: aeroelectric-list(at)matronics.com
>Subject: AeroElectric-List: Microprocessor based Fuel Gauge Linearizer
>
>
>
>Neil Hulin's comment about using a fuel totalizer instead of a fuel
>gauge linearizer has been burning a hole in my brain. I believe he is
>right....
>
>Here's the deal--
>
>You only need one fuel totalizer meter if you take fuel from only one
>tank at a time. The fuel quantity meter (and memory) for that tank is
>simply updated as required. I trust in this system, totalizers really
>work well.
>Consider too, that you wouldn't need fuel-level senders or gauges at
>all. Always problematic devices. You also would not need anti-slosh
>electronic filters either. My airplane just got a whole lot lighter!
>
>There are a few practical concerns--how do we know the tank is at the
>level the "gauge" says it is? Well, I always checked it visually with a
>wooden stick anyway. So when tanks are refilled they must be filled to
>the top (ideally) and visually checked. You really wanted the fuel flow
>rate anyway. Not a bad tradeoff.
>
>Eric M. Jones
>
>The whole difference between construction and creation is exactly this:
>that a thing constructed can only be loved after it is constructed;
>but a thing created is loved before it exists.
>- Charles Dickens
>
>
>
>
________________________________________________________________________________
| From: | "Tom Schiff" <tomschiff(at)attbi.com> |
| Subject: | Microprocessor based Fuel Gauge Linearizer |
I have heard that capacitive gages will not work with Jet-A because
there is some water dissolved in the fuel which gives it some
conductivity. You may be able to use insulated sensors.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Wolfgang Trinks
Subject: Re: AeroElectric-List: Microprocessor based Fuel Gauge
Linearizer
I agree that a fuel totalizer in combination with a fuel gauge with a
certain tolerance but precisly showing low fuel situation is a
reasonable
way to go.
But there are also others:
I did linearize a the fuel gauge once on my daycruiser(boat). What
appeared
to be a weekend programming job on a 80C515 turned into a small >Joint
Strike Fighter< project.
First of all, giving the situation of flat tanks with irregular shapes
you
have to determine the funtion of fuel volume versus measuring height of
your
sensor at a given sensor position mathematicly using linear algebra.
This is
a must.
As this can turn into a nightmare espacially if the tank is inclined
during
climb or decent there is a way making things easier(You can neglect bank
because a plane is flown coordinated 99% of the fight time).
Devide your tank in your mind into boxes and put a sensor in the middle
of
each box. The smaller the boxes the lower is the influence of the
incline
and the more precisly you can determine the volume versus measuring
height
by simple trigometrie. The sum of all sensor added one by one will be
the
full tank reading where the max value of every sensor equals the
contribution of his box to the total volume. The more boxes, the more
precise and more expensive. So there must be a compromise, but this is
strongly dependent on the shape of the tank.
Anyway when I did this I programmed my f(fuel) in a pascal programm
where I
simulated the different incline and was able to play arround with the
number
and position of the virtual boxes. It turned out that I could come below
1%
error with 3 sensors on a tank measuring 80cm x 50cm x 180cm in angles
up to
15 degree in most unfavourable axis. This was a quite positive
experiance. I
think also for a plane with a LL100 grade burning engine 15 degree of
continious pitch up during climb should be far enough.
If you do this you have got the problem on the root and depending on the
type of sensor there will be hardly any linearizing nessecary.
On my boat I used VDO linear resistence floaters and the results where
perfect.
If I would have to do it on a plane today I would use a capacitive
system as
sensors because you could very easily build your own sensors (basic
machining required) and finetune the sensors to the tank shape.It also
shows
the weight of fuel in the tanks which is the correct measure for your
endurance(ok, this is academic with those tiny volumes).
To get a feeling for all this just look what the big ones are doing if
they
need fuel indicators that are serious(Cessna 340,414, King Air,
Citation,
all big jets)
Wolfgang...
----- Original Message -----
From: "Tom Schiff" <tomschiff(at)attbi.com>
Subject: RE: AeroElectric-List: Microprocessor based Fuel Gauge
Linearizer
>
> The problem is that the FAA requires that there be a fuel gage but
only
> requires that is shows when the tank is empty. I have been using a
fuel
> flow in my C-150 for several months. I have been updating the amount
> remaining every time I fill by the exact amount that I have filled. It
> has been agreeing with the amount determined by sticking the tanks.
> After many fills and over 100 gallons of fuel burned it is still
within
> .2 gallons. So you could probably get away with a fuel gage that is in
> reality a fuel flow gage but if you got caught you would be in
trouble.
>
> My ideal fuel gage would be several sensors of the type where a led
> shines a light through a prism. When the prism is submerged in gas the
> light shines on a photo sensor and indicates that the sensor is below
> the level of the fuel. The sensors would be at various levels in each
> tank an they would light two sets of led indicators on in the cockpit
> and another aggacent to the filler port. I this way I would know when
I
> was about to overfill the tanks. I saw a Money that had a fuel gage
next
> to the filler port and that is where I got the idea from. Because you
> have absolutle freedom where you place the sensors you wouldn't have
to
> worry about the non linearitys of flat tanks that are inclined at an
> angle
>
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Eric
> M. Jones
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: Microprocessor based Fuel Gauge Linearizer
>
>
>
> Neil Hulin's comment about using a fuel totalizer instead of a fuel
> gauge linearizer has been burning a hole in my brain. I believe he is
> right....
>
> Here's the deal--
>
> You only need one fuel totalizer meter if you take fuel from only one
> tank at a time. The fuel quantity meter (and memory) for that tank is
> simply updated as required. I trust in this system, totalizers really
> work well.
> Consider too, that you wouldn't need fuel-level senders or gauges at
> all. Always problematic devices. You also would not need anti-slosh
> electronic filters either. My airplane just got a whole lot lighter!
>
> There are a few practical concerns--how do we know the tank is at the
> level the "gauge" says it is? Well, I always checked it visually with
a
> wooden stick anyway. So when tanks are refilled they must be filled to
> the top (ideally) and visually checked. You really wanted the fuel
flow
> rate anyway. Not a bad tradeoff.
>
> Eric M. Jones
>
> The whole difference between construction and creation is exactly
this:
> that a thing constructed can only be loved after it is constructed;
> but a thing created is loved before it exists.
> - Charles Dickens
>
>
________________________________________________________________________________
| From: | Duncan McBride <duncanmcbride(at)comcast.net> |
| Subject: | Headphone noise on transmit |
I've been fussing with what seemed to be ignition or alternator noise in my radio
when I pushed the PTT on my Microair 760. I posted to the list a while back,
and tried a different power source and a different antenna. The noise was
there even when powered from a separate battery. Here is the thing: the noise
is a loud hiss that I only hear when transmitting. Reception is clear as a
bell. What I found out today is that my transmissions are clear as well. I
spoke with another pilot sharing the pattern as we self-announced our way into
Avon Park this morning and he said my signal was loud and clear, no hiss or any
noise. It seems the noise is only coming out my headphones. I experimented
and found the noise is independent of the radio volume but decreases if I turn
down the headphones, so I can mitigate it somewhat by turning down the headphones
and turning up the radio volume. These are twenty year old David Clark
H10-80 'phones they don't make anymore. I haven't tried any
t could they be the problem?
________________________________________________________________________________
| From: | "Paul McAllister" <paul.mcallister(at)qia.net> |
| Subject: | Re: Source for Pins & Extraction tools |
Hi Bob,
I purchased 50 sockets, but to no avail, well almost. They fitted the 37
pin D Style connector on the SL70 transponder, but not the 37 pin connector
for the GX60.
The sockets wouldn't slide all the way in and when I examined them closely
the sockets that did fit had a split on the front and the barrel was about
10 thou smaller. I found that the 15 pin connector on the GX60 and the 37
pin on the Narco Nav 122 had the same problem.
Any idea on where to get this style of pin? I can send you an example if it
would help.
Thanks, Paul
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: Source for Pins & Extraction tools
>
> >
> >
> >Hi all,
> >
> >I am approaching the stage where I will be wiring up my UPS GX60 Nav/Com
&
> >SL 70 transponder. The units come supplied with 37 pin D style
connectors
> >and I am seeking some advice.
> >
> >Where can I purchase a suitable crimping tool, insertion/extraction tool
> >and some pins & sockets.
>
>
> See:
>
> http://www.aeroelectric.com/Catalog/tools/tools.html#rct-3
> http://www.aeroelectric.com/Catalog/tools/tools.html#dse-1
> http://www.aeroelectric.com/Catalog/connect/connect.html#S604
> http://www.aeroelectric.com/Catalog/BCcatalog.html
>
>
> > I would be interested to know what size wire do people typically use
in
> > these pins to ensure a good crimp
>
> 24-20 AWG wire works well in these pins. 20AWG for
> power/ground and 22AWG for everything else is
> good . . .
>
>
> Bob . . .
>
>
> --------------------------------------------
> ( Knowing about a thing is different than )
> ( understanding it. One can know a lot )
> ( and still understand nothing. )
> ( C.F. Kettering )
> --------------------------------------------
>
>
________________________________________________________________________________
| From: | "Bill Steer" <bsteer(at)gwi.net> |
| Subject: | Re: Source for Pins & Extraction tools |
----- Original Message -----
From: "Paul McAllister" <paul.mcallister(at)qia.net>
Subject: Re: AeroElectric-List: Source for Pins & Extraction tools
>
> Hi Bob,
>
> I purchased 50 sockets, but to no avail, well almost. They fitted the 37
> pin D Style connector on the SL70 transponder, but not the 37 pin connector
> for the GX60.
>
> The sockets wouldn't slide all the way in and when I examined them closely
> the sockets that did fit had a split on the front and the barrel was about
> 10 thou smaller. I found that the 15 pin connector on the GX60 and the 37
> pin on the Narco Nav 122 had the same problem.
>
> Any idea on where to get this style of pin? I can send you an example if it
> would help.
>
> Thanks, Paul
>
>
> ----- Original Message -----
> From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
> To:
> Subject: Re: AeroElectric-List: Source for Pins & Extraction tools
>
>
>
> >
> > >
> > >
> > >Hi all,
> > >
> > >I am approaching the stage where I will be wiring up my UPS GX60 Nav/Com
> &
> > >SL 70 transponder. The units come supplied with 37 pin D style
> connectors
> > >and I am seeking some advice.
> > >
> > >Where can I purchase a suitable crimping tool, insertion/extraction tool
> > >and some pins & sockets.
> >
> >
> > See:
> >
> > http://www.aeroelectric.com/Catalog/tools/tools.html#rct-3
> > http://www.aeroelectric.com/Catalog/tools/tools.html#dse-1
> > http://www.aeroelectric.com/Catalog/connect/connect.html#S604
> > http://www.aeroelectric.com/Catalog/BCcatalog.html
> >
> >
> > > I would be interested to know what size wire do people typically use
> in
> > > these pins to ensure a good crimp
> >
> > 24-20 AWG wire works well in these pins. 20AWG for
> > power/ground and 22AWG for everything else is
> > good . . .
> >
> >
> > Bob . . .
> >
> >
> > --------------------------------------------
> > ( Knowing about a thing is different than )
> > ( understanding it. One can know a lot )
> > ( and still understand nothing. )
> > ( C.F. Kettering )
> > --------------------------------------------
> >
> >
>
>
________________________________________________________________________________
| From: | "Rob W M Shipley" <Rob(at)RobsGlass.com> |
| Subject: | : The value talking about simple-ideas . . . |
I would like to most emphatically endorse Phil's email thanking especially Bob
and also the other technically able contributors.
The single invaluable benefit I have got from you all is an albeit shaky grip on
how to look at a problem. It's the logic of how and why that is so valuable.
Not to devalue the tech stuff, help with this is vital too but the mental light
bulb that goes on when you understand why doing 'this' and not 'that' is
the safest and most efficient method is (like my wife's Visa purchases) absolutely
priceless.
Thanks again guys.
Rob
Rob W M Shipley
RV9A N919RV Fuselage - now a canoe!!!
________________________________________________________________________________
| From: | "Rob W M Shipley" <Rob(at)RobsGlass.com> |
| Subject: | Unnecessary fuel gauges!!!? |
Neil Hulin's comment about using a fuel totalizer instead of a fuel gauge linearizer
has been burning a hole in my brain. I believe he is right....
Here's the deal--
You only need one fuel totalizer meter if you take fuel from only one tank at a
time. The fuel quantity meter (and memory) for that tank is simply updated as
required. I trust in this system, totalizers really work well.
Consider too, that you wouldn't need fuel-level senders or gauges at all. Always
problematic devices. You also would not need anti-slosh electronic filters
either. My airplane just got a whole lot lighter!
There are a few practical concerns--how do we know the tank is at the level the
"gauge" says it is? Well, I always checked it visually with a wooden stick anyway.
So when tanks are refilled they must be filled to the top (ideally) and
visually checked. You really wanted the fuel flow rate anyway. Not a bad tradeoff.
This is a nice idea but what happens if fuel is lost from the system anywhere
on the tank side of totalizer sender? e.g. loose fuel cap, cracked pipe etc.
Now your totalizer is telling you that full fuel, less that burned in the engine,
remains. Not!
Also I may be wrong but I have this hazy memory of the Feds, (always here to help),
requiring gauges ......
Don't get me wrong. I think totalizers are a terrific idea but a pair of steam
fuel gauges a watch and knowledge of approximate fuel burn make a terrific cross
check with each other to confirm what you actually have to get you home.
Bit like doing a mental approximation of a problem to check you hit the right
buttons on the calculator or in this case that your totalizer figures are valid.
Fly safe
Rob
Rob W M Shipley
RV9A N919RV Fuselage - now a canoe!!!
________________________________________________________________________________
| From: | "Tony Babb" <tonybabb(at)alejandra.net> |
| Subject: | Re: Unnecessary fuel gauges!!!? |
I like the idea of the totalizer and agree the only unknowns are - what
happens if a fuel cap comes loose and what does the FAA need. I was planning
on going with fuel gauges and Vance Atkinson sight gauges, now I'm thinking
a totalizer and sight gauges would do the job. In the event that there is a
leak I could see what's happening and in any case would get a warning when
the low-fuel light in the sump tank (or whatever it's called) comes on.
----- Original Message -----
From: "Rob W M Shipley" <Rob(at)RobsGlass.com>
Subject: AeroElectric-List: Unnecessary fuel gauges!!!?
>
>
>
> Neil Hulin's comment about using a fuel totalizer instead of a fuel gauge
linearizer
> has been burning a hole in my brain. I believe he is right....
>
> Here's the deal--
>
> You only need one fuel totalizer meter if you take fuel from only one tank
at a
> time. The fuel quantity meter (and memory) for that tank is simply updated
as
> required. I trust in this system, totalizers really work well.
> Consider too, that you wouldn't need fuel-level senders or gauges at all.
Always
> problematic devices. You also would not need anti-slosh electronic
filters
> either. My airplane just got a whole lot lighter!
>
> There are a few practical concerns--how do we know the tank is at the
level the
> "gauge" says it is? Well, I always checked it visually with a wooden stick
anyway.
> So when tanks are refilled they must be filled to the top (ideally) and
> visually checked. You really wanted the fuel flow rate anyway. Not a bad
tradeoff.
>
> This is a nice idea but what happens if fuel is lost from the system
anywhere on the tank side of totalizer sender? e.g. loose fuel cap, cracked
pipe etc. Now your totalizer is telling you that full fuel, less that
burned in the engine, remains. Not!
> Also I may be wrong but I have this hazy memory of the Feds, (always here
to help), requiring gauges ......
> Don't get me wrong. I think totalizers are a terrific idea but a pair of
steam fuel gauges a watch and knowledge of approximate fuel burn make a
terrific cross check with each other to confirm what you actually have to
get you home. Bit like doing a mental approximation of a problem to check
you hit the right buttons on the calculator or in this case that your
totalizer figures are valid.
> Fly safe
> Rob
> Rob W M Shipley
> RV9A N919RV Fuselage - now a canoe!!!
>
>
________________________________________________________________________________
| From: | "Gary Casey" <glcasey(at)adelphia.net> |
| Subject: | Fuel level indicators |
I'll have to weigh in in favor of retaining a fuel level indicator,
regardless of whether a fuel flow meter (totalizer) is installed. The
reason is simple - the totalizer REQUIRES active intervention of the pilot
to work. He has to set in the quantity of fuel added EACH time or the
system won't work. While designing our planes I think it is most important
to design in protection against ourselves - accident studies have shown that
it is ourselves that are the weak link. It scares me to hear things like "I
dipstick the tanks every time." Every time? Every time in the future? I
do a lot of audits of manufacturing systems and it's easy - just listen for
the words "every," "always" and "never." That will usually be the problem,
or at least a problem waiting to happen. A fuel level gauge works
regardless of any action by the pilot. And that is its advantage.
Gary Casey
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Fuel level indicators |
In a message dated 5/19/03 7:48:26 AM Central Daylight Time,
glcasey(at)adelphia.net writes:
> While designing our planes I think it is most important
> to design in protection against ourselves - accident studies have shown
> that
> it is ourselves that are the weak link. It scares me to hear things like
> "I
> dipstick the tanks every time." Every time? Every time in the future? I
> do a lot of audits of manufacturing systems and it's easy - just listen for
> the words "every," "always" and "never." That will usually be the problem,
> or at least a problem waiting to happen. A fuel level gauge works
> regardless of any action by the pilot. And that is its advantage.
>
> Gary Casey
>
>
Good Morning Gary,
Nicely said, thanks.
Your statement says more about air safety than almost any other similar
length statement I have ever read
Air safety is the realization that we all make mistakes. As long as we can
avoid that trap of saying; "That could never happen to me, because I
always----------------" We have a reasonable chance of living to a Ripe Old
Age.
Happy Skies,
Old Bob
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Fuel level indicators |
In a message dated 5/19/03 7:48:26 AM Central Daylight Time,
glcasey(at)adelphia.net writes:
> I'll have to weigh in in favor of retaining a fuel level indicator,
> regardless of whether a fuel flow meter (totalizer) is installed.
Good Morning Once Again,
I should have commented here as well. I'm with you!
I particularly like the idea of sight gauges on tanks where that will work.
I have them on my tip tanks, wish they could be used on my very unreliably
gauged main tanks.
Happy Skies.
Old Bob
________________________________________________________________________________
| From: | "Dennis O'Connor" <doconnor(at)chartermi.net> |
| Subject: | Re: Fuel level indicators |
Unfortunately, the pilot of the Lancair 4P this weekend didn't believe the
old story about avoiding thunderstorms...
Denny
----- Original Message -----
From: <BobsV35B(at)aol.com>
Subject: Re: AeroElectric-List: Fuel level indicators
>
> In a message dated 5/19/03 7:48:26 AM Central Daylight Time,
> glcasey(at)adelphia.net writes:
>
> > While designing our planes I think it is most important
> > to design in protection against ourselves - accident studies have shown
> > that
> > it is ourselves that are the weak link. It scares me to hear things
like
> > "I
> > dipstick the tanks every time." Every time? Every time in the future?
I
> > do a lot of audits of manufacturing systems and it's easy - just listen
for
> > the words "every," "always" and "never." That will usually be the
problem,
> > or at least a problem waiting to happen. A fuel level gauge works
> > regardless of any action by the pilot. And that is its advantage.
> >
> > Gary Casey
> >
> >
>
> Good Morning Gary,
>
> Nicely said, thanks.
>
> Your statement says more about air safety than almost any other similar
> length statement I have ever read
>
> Air safety is the realization that we all make mistakes. As long as we
can
> avoid that trap of saying; "That could never happen to me, because I
> always----------------" We have a reasonable chance of living to a Ripe
Old
> Age.
>
> Happy Skies,
>
> Old Bob
>
>
________________________________________________________________________________
| From: | brucem(at)olypen.com |
| Subject: | Unnecessary fuel gauges!!!? |
Sorry, but FAR 91.205(b)(9) requires a fuel gauge indicating the quantity of
fuel in each tank.
Bruce McGregor
(GlaStar)
---------------------------------------------
This message was sent using OlyPen's WebMail.
http://www.olypen.com
________________________________________________________________________________
| From: | "Rick Caldwell" <racaldwell(at)hotmail.com> |
| Subject: | Re: Unnecessary fuel gauges!!!? |
>Don't get me wrong. I think totalizers are a terrific idea but a pair of
>steam fuel gauges a watch and knowledge of approximate fuel burn make a
>terrific cross check with each other to confirm what you actually have to
>get you home. Bit like doing a mental approximation of a problem to check
>you hit the right buttons on the calculator or in this case that your
>totalizer figures are valid.
>Fly safe
>Rob
>Rob W M Shipley
>RV9A N919RV Fuselage - now a canoe!!!
Rob,
The fuel guages in my RV-6 are basically worthless. The wing tanks are at
the wing dihedral angle. The flop tube in the left wing tank necessitates
the sender be mounted further toward tank center. The right tank sender is
not completely at the low point in the tank. Far from it actually.
Therefore, when both guages read empty, I have about 5 gal. in the left tank
and 2 gal. in the right. That is 1 hr of flight at 65% power. Of course I
normally do not fly around with 7 gal. remaining but I am legally allowed to
fly with about 4 gal.
I use my fuel totalizer. On a recent X-C, I had to revise flight plans due
to lowering ceilings ahead. I returned back to the sunny blue skies of FL.
I had fuel to make it to a fuel stop with 5 gal on board after landing or
stop sooner and pay $1/gal. more. I chose to save the money. However, try
telling your nonflying wife why you are flying with both fuel guages on
empty. The digital fuel remaining readout did nothing for calming her fears.
I did not know this until after landing. Otherwise, I would have paid the
$3.25/gal. The fuel guages did me no favors that day. Wish I didn't have
them.
Rick Caldwell
RV-6
One Design
________________________________________________________________________________
| Subject: | Re: Fuel level indicators |
| From: | John Schroeder <jschroeder(at)perigee.net> |
Dennis -
I believe it is a tad early to make this conclusion.
John
> Unfortunately, the pilot of the Lancair 4P this weekend didn't believe
> the old story about avoiding thunderstorms...
>
> Denny
________________________________________________________________________________
| From: | "nhulin" <nhulin(at)hotmail.com> |
| Subject: | Re: Unnecessary fuel gauges!!!? |
Listers,
I hadn't looked at the digests for a couple of days. Looks like this one has
generated some interest.
I'd like to clarify the comment in my post. I wasn't advocating doing away
with the gauges, whether steam or processor, float or capacitive. I was
simply stating that there are mechanical limitations in that some of the
information required to be displayed might not be available due to the
configuration of the senders or the tanks. If I was going to spend money to
solve this problem then I'd prefer to spend it on a totalizer rather than
fixing the gauges I already have. One complements the other as others have
pointed out. Sort of like how the flight planning fuel consumption
calculation complements watching the gauges while in flight - everyone still
does that don't they?
Rick Caldwell correctly points out that in some configurations you can have
fuel remaining above unusable fuel when the gauge reads zero. This is what I
expect in my Zodiac. There would be hundreds of other aircraft out there in
the same situation. I don't see that there is anything that can be done
about that except review the entire fuel system and engineer a suitable
solution which may or may not include some sort of linearizer.
It is also true that Rick's gauges still read zero when there is only
unusable quantity of fuel. Hmmm. On a technical point we've satisfied
23.959(a) except that it might not be considered "calibrated" if it reads
zero for many quantities including unusable fuel. Simply because we consider
a statement to be true doesn't mean that it is of benefit to anyone. I agree
with Rick that flying for an hour or more with gauges on zero might be a bit
disconcerting.
For my Zodiac, I'll be happy with a full reading being clearly marked as
">10.5 gallons". I still need to dip the tanks during preflight if I am
getting close to max gross and am concerned about having too much fuel. At
the bottom end of the scale I'll know that I need to land and refuel when
the gauges get down towards zero. I didn't spend all this time building a
powered aircraft just to turn it into a glider.
...neil
601XL
Cincinnati
________________________________________________________________________________
| From: | "Ed Anderson" <eanderson(at)carolina.rr.com> |
| Subject: | Re: Unnecessary fuel gauges!!!? |
I think you will find that what ever the FSDO approving your Operating
limitations puts into that document is what you are obligated to follow.
Mine has a number of references to paragraphs of FAR 91 that I must comply
with, your milage may vary..
Ed Anderson
RV-6A N494BW 200 Rotary Powered Hours
Matthews, NC
eanderson(at)carolina.rr.com
________________________________________________________________________________
| From: | "Richard V. Reynolds" <rvreynolds(at)macs.net> |
| Subject: | Re: Source for Pins & Extraction tools |
Paul,
Call UPS/Apollo Tech support and ask them to send the pins. They will want to know
they
manufacture of the socket and the "color". Two different sockets have been used.
If you have the ACU also with the 78 pin connector, IT IS VERY IMPORTANT to use
the
correct pins and the correct AMP crimping tool. It only cost $150, but if you don't
use
the correct tool, the pins will not fit the connector correctly and YOU WILL NOT
be
able to EXTRACT them!!!!
Richard Reynolds, A happy did it myself wiring UPS/Apollo.
Paul McAllister wrote:
>
> Hi Bob,
>
> I purchased 50 sockets, but to no avail, well almost. They fitted the 37
> pin D Style connector on the SL70 transponder, but not the 37 pin connector
> for the GX60.
>
> The sockets wouldn't slide all the way in and when I examined them closely
> the sockets that did fit had a split on the front and the barrel was about
> 10 thou smaller. I found that the 15 pin connector on the GX60 and the 37
> pin on the Narco Nav 122 had the same problem.
>
> Any idea on where to get this style of pin? I can send you an example if it
> would help.
>
> Thanks, Paul
>
> ----- Original Message -----
> From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
> To:
> Subject: Re: AeroElectric-List: Source for Pins & Extraction tools
>
>
> >
> > >
> > >
> > >Hi all,
> > >
> > >I am approaching the stage where I will be wiring up my UPS GX60 Nav/Com
> &
> > >SL 70 transponder. The units come supplied with 37 pin D style
> connectors
> > >and I am seeking some advice.
> > >
> > >Where can I purchase a suitable crimping tool, insertion/extraction tool
> > >and some pins & sockets.
> >
> >
> > See:
> >
> > http://www.aeroelectric.com/Catalog/tools/tools.html#rct-3
> > http://www.aeroelectric.com/Catalog/tools/tools.html#dse-1
> > http://www.aeroelectric.com/Catalog/connect/connect.html#S604
> > http://www.aeroelectric.com/Catalog/BCcatalog.html
> >
> >
> > > I would be interested to know what size wire do people typically use
> in
> > > these pins to ensure a good crimp
> >
> > 24-20 AWG wire works well in these pins. 20AWG for
> > power/ground and 22AWG for everything else is
> > good . . .
> >
> >
> > Bob . . .
> >
> >
> > --------------------------------------------
> > ( Knowing about a thing is different than )
> > ( understanding it. One can know a lot )
> > ( and still understand nothing. )
> > ( C.F. Kettering )
> > --------------------------------------------
> >
> >
>
________________________________________________________________________________
| From: | John Herminghaus <catignano(at)everyday.com> |
| Subject: | Alternator fields |
Bob,
The alternator on my TSIO 550 has three small studs marked F1, F2 and
Aux. How should it be connected to an LR3c?
Regards,
John Herminghaus
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
| Subject: | Z-13 mod'd by David Carter |
Request "peer review"/comments/questions on the attached Autocad/Intellicad drawing
(.dwg file)
At the lower center part of drawing, there are 4 changes that I've made which I'd
like comments on.
I'm designing a "single PM alternator with 2 17ah batteries" system to power an
electrically dependent Mazda rotary engine (electronic fuel inj & ignition).
I've yet to add "battery busses" and details of what instruments, etc will feed
off the main and endurance and battery 1 & 2 busses. I'm seeking "validation"
of my basic concept, before I go into those details.
I don't know how to make this drawing viewable by those without a cad program.
When I convert to .bmp and to .jpg format, I only get the part of the drawing
that shows on the screen. So, . . .
if anyone wants it in .jpg, I'll get the upper left and right and lower left
and right quarters of the dwg zoomed in enough so all details are readable,
and make 4 images (.bmp to .jpg conversion) and attach all 4 to an e-mail so
anyone can see open and see each quarter of the drawing.
David Carter
RV-6
Nederland, Texas
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
| Subject: | Re: Z-13 mod'd by David Carter |
What have I missed on use of the list? The file I attached was stripped in
process of being posted to the AeroElectric List. I re-checked my "Sent"
file and the dwg was attached when I clicked "Send".
What do I need to do? Put it on my web site and provide a link? Can do
that.
David
----- Original Message -----
From: "David Carter" <dcarter(at)datarecall.net>
Subject: AeroElectric-List: Z-13 mod'd by David Carter
>
> Request "peer review"/comments/questions on the attached
Autocad/Intellicad drawing (.dwg file)
> At the lower center part of drawing, there are 4 changes that I've made
which I'd like comments on.
>
> I'm designing a "single PM alternator with 2 17ah batteries" system to
power an electrically dependent Mazda rotary engine (electronic fuel inj &
ignition).
>
> I've yet to add "battery busses" and details of what instruments, etc will
feed off the main and endurance and battery 1 & 2 busses. I'm seeking
"validation" of my basic concept, before I go into those details.
>
> I don't know how to make this drawing viewable by those without a cad
program. When I convert to .bmp and to .jpg format, I only get the part of
the drawing that shows on the screen. So, . . .
> if anyone wants it in .jpg, I'll get the upper left and right and
lower left and right quarters of the dwg zoomed in enough so all details
are readable, and make 4 images (.bmp to .jpg conversion) and attach all 4
to an e-mail so anyone can see open and see each quarter of the drawing.
>
> David Carter
> RV-6
> Nederland, Texas
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Alternator fields |
>
>
>Bob,
>
>The alternator on my TSIO 550 has three small studs marked F1, F2 and
>Aux. How should it be connected to an LR3c?
Ground either F1 or F2, run other "F" to output of LR3. Ignore "Aux"
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 mod'd by David Carter |
>
>
>What have I missed on use of the list? The file I attached was stripped in
>process of being posted to the AeroElectric List. I re-checked my "Sent"
>file and the dwg was attached when I clicked "Send".
>
>What do I need to do? Put it on my web site and provide a link? Can do
>that.
>
>David
The list server will not pass attachments. This potential
stress on the server for volume of traffic it can handle
and eliminates the propagation of virii.
Yes, if you can post your attachments to a server you
have access to along with a link to that attachment,
it's the way to go.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Cheap blind encoder. |
Gang,
Bob wrote: <>
A little follow up. Couldn't find a fresh 9V around the shop last
night, so I simply e-mailed Narco. For the record, Narco
confirms that the AT-150 xponder does not have an internal isolation diode
on each encoder line. You must add your own if you parallel the encoder to
the xponder and another device. In this case the other device (GNS430)
already has them, so I only need one set.
Dan
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
| Subject: | Re: Z-13 mod'd by David Carter |
Ref my initial, modified version of Z-13 for "electrically dependent
engine" (2 batteries, 1 PM John Deere Alternator & voltage regulator):
- I'll send the .dwg file attached to an e-mail to anyone who asks in
pvt e-mail who has a CAD pgm that can open it and zoom & pan. (can send as
.dwg or .dxf). So far that is Eric Jones & Bob Nuckolls. Larry Helming
needs .jpg
- Further, today I'll experiement with exporting "what is on the screen"
to .bmt and converting to .jpg to see how much detail is saved in this
process - yesterday when I tried this I only got what was on the screen (a
highly zoomed view that left out most of the schematic, not the entire
drawing).
David Carter
________________________________________________________________________________
| From: | Richard Tasker <retasker(at)optonline.net> |
| Subject: | Re: Z-13 mod'd by David Carter |
If you are running Windows (of any sort) you can export from AutoCAD
using the WMF format. This is a vector format that is readable in
virtually any Windows program and is scalable. That is, you can put the
entire drawing on the screen, export it to WMF (just select all when
asked) and then someone can view it in various windows programs and pan
and zoom to see the details. It is NOT a bitmap file, so it keeps the
detail at any size - just like the original in AutoCAD.
Or you could download one of the free PDF converter clones to convert it
to PDF format.
Or people who would like to view AutoCAD files but don't have AutoCAD
could download Voloview - a free AutoCAD viewer at:
http://usa.autodesk.com/adsk/servlet/index?siteID=123112&id=837403
This allows viewing and printing (but not modification).
Dick Tasker, 90573
RV-9A right wing
David Carter wrote:
>
>Request "peer review"/comments/questions on the attached Autocad/Intellicad drawing
(.dwg file)
>At the lower center part of drawing, there are 4 changes that I've made which
I'd like comments on.
>
>I'm designing a "single PM alternator with 2 17ah batteries" system to power an
electrically dependent Mazda rotary engine (electronic fuel inj & ignition).
>
>I've yet to add "battery busses" and details of what instruments, etc will feed
off the main and endurance and battery 1 & 2 busses. I'm seeking "validation"
of my basic concept, before I go into those details.
>
>I don't know how to make this drawing viewable by those without a cad program.
When I convert to .bmp and to .jpg format, I only get the part of the drawing
that shows on the screen. So, . . .
> if anyone wants it in .jpg, I'll get the upper left and right and lower left
and right quarters of the dwg zoomed in enough so all details are readable,
and make 4 images (.bmp to .jpg conversion) and attach all 4 to an e-mail so
anyone can see open and see each quarter of the drawing.
>
>David Carter
>RV-6
>Nederland, Texas
>
>
>
>
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
| Subject: | Re: Z-13 mod'd by David |
Carter)
Richard, you get the "gold star" today!!
I'll try that .wmf format and try viewing it before sending it out. Thanks
for the excellent tips on viewers that others can use. I'm definitely going
to get a .pdf file creator - Bob Nuckolls has also given some coaching on
this - just haven't got that far yet.
David
----- Original Message -----
From: "Richard Tasker" <retasker(at)optonline.net>
Subject: Re: AeroElectric-List: Z-13 mod'd by David Carter
>
> If you are running Windows (of any sort) you can export from AutoCAD
> using the WMF format. This is a vector format that is readable in
> virtually any Windows program and is scalable. That is, you can put the
> entire drawing on the screen, export it to WMF (just select all when
> asked) and then someone can view it in various windows programs and pan
> and zoom to see the details. It is NOT a bitmap file, so it keeps the
> detail at any size - just like the original in AutoCAD.
>
> Or you could download one of the free PDF converter clones to convert it
> to PDF format.
>
> Or people who would like to view AutoCAD files but don't have AutoCAD
> could download Voloview - a free AutoCAD viewer at:
>
> http://usa.autodesk.com/adsk/servlet/index?siteID=123112&id=837403
>
> This allows viewing and printing (but not modification).
>
> Dick Tasker, 90573
> RV-9A right wing
>
> David Carter wrote:
>
> >
> >Request "peer review"/comments/questions on the attached
Autocad/Intellicad drawing (.dwg file)
> >At the lower center part of drawing, there are 4 changes that I've made
which I'd like comments on.
> >
> >I'm designing a "single PM alternator with 2 17ah batteries" system to
power an electrically dependent Mazda rotary engine (electronic fuel inj &
ignition).
> >
> >I've yet to add "battery busses" and details of what instruments, etc
will feed off the main and endurance and battery 1 & 2 busses. I'm seeking
"validation" of my basic concept, before I go into those details.
> >
> >I don't know how to make this drawing viewable by those without a cad
program. When I convert to .bmp and to .jpg format, I only get the part of
the drawing that shows on the screen. So, . . .
> > if anyone wants it in .jpg, I'll get the upper left and right and
lower left and right quarters of the dwg zoomed in enough so all details
are readable, and make 4 images (.bmp to .jpg conversion) and attach all 4
to an e-mail so anyone can see open and see each quarter of the drawing.
> >
> >David Carter
> >RV-6
> >Nederland, Texas
> >
> >
> >
> >
>
>
________________________________________________________________________________
| Subject: | Re: Z-13 mod'd by David Carter |
| From: | John Schroeder <jschroeder(at)perigee.net> |
David
I believe that Bob Nuckolls can convert to a pdf file from autocad. He also
can post it temporarily on his website for folks to download. Bob already
has a copy of your .dwg file. If he is tied up, email me a .dwg file and I
can convert to .pdf file for you.
John Schroeder
> - I'll send the .dwg file attached to an e-mail to anyone who asks in
> pvt e-mail who has a CAD pgm that can open it and zoom & pan. (can send
> as .dwg or .dxf). So far that is Eric Jones & Bob Nuckolls. Larry
> Helming
> needs .jpg
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 modified for different control of PM alternator |
>The CAD drawing is attached. Thanks for taking a look at it.
You've made a considerable number of changes to drawing(s)
that have been thoughtfully evolved for a number of years.
In fact, so many changes that it would take me a long time
to do a detailed critical analysis. Can we take a more organized
approach? If you plan dual robust alternators and dual batteries then
choices from the published drawings are:
Z-12 with second battery per Z-30
and
Z-14
Starting with either one of these, can you cite perceived
shortcomings to meet your needs?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 mod'd by David Carter |
>
>
>Ref my initial, modified version of Z-13 for "electrically dependent
>engine" (2 batteries, 1 PM John Deere Alternator & voltage regulator):
> - I'll send the .dwg file attached to an e-mail to anyone who asks in
>pvt e-mail who has a CAD pgm that can open it and zoom & pan. (can send as
>.dwg or .dxf). So far that is Eric Jones & Bob Nuckolls. Larry Helming
>needs .jpg
I tried to .pdf your drawing but for some reason, AutoCAD finds
over 1700 entities in the drawing and the .pdf version is nearly
3 megabytes. Not sure what's going on with it but it's too big
to be a practical download for sharing with any conversion
software I have here.
Bob . . .
________________________________________________________________________________
| From: | BAKEROCB(at)aol.com |
| Subject: | Application of FAR Part 91to ABEA |
5/20/2003
AeroElectric-List message posted by: SportAV8R(at)aol.com
In a message dated 05/19/2003 12:48:01 PM Eastern Daylight Time,
brucem(at)olypen.com writes:
> Sorry, but FAR 91.205(b)(9) requires a fuel gauge indicating the quantity
of
> fuel in each tank. Bruce McGregor (GlaStar)
<>
Hello SportAV8R, I suspect that you must be kidding. Of course FAR Part 91,
The General Operating and Flight Rules, applies to the operation of ABEA
(Amateur Built Expeimental Aircraft). After Phase One testing is completed and
the
aircraft is being flown around the country just like a standard type
certificated airplane FAR Part 91 does indeed apply. (During Phase One testing
much more
stringent operating rules apply).
The Operating Limitations** issued for each ABEA will also call out
specifically some of the Part 91's that must be complied with or met such as 91.205,
which, in 91.205 (b) (9), requires a "Fuel Gauge indicating the quantity of fuel
in each tank".
Other parts of FAR 91 dealing with flight operations will start out with such
language as "No person may _____________ unless_____________". (See 91.107
for example). Such prohibitions / limitations / requirements apply to the ABEA
and its pilot just as they do to any other aircraft operating in our airspace.
Can you please identify some Part 91 General Operating and Flight Rules that
do not apply to ABEA? Thank you.
'OC' Baker, Builder of KIS TR-1 #116 4/14/97 - ?/?/?
**PS: I will repost some extracts from recently issued ABEA Operating
Limitations if you like or you can find them in the archives.
PPS: Ed Anderson makes the point in his posting on this subject that there is
some variability from FSDO to FSDO on how things are done. This is true. Each
FAA Inspector or DAR (Designated Airworthiness Representative) has some
leeway as he inspects a new ABEA and he has considerable power as he is acting
on
behalf of the FAA Administrator.
But instructions to the Inspector or DAR, including the wording of the
Operation Limitation, is provided by FAA Order 8130.2E so there is much
standardization in that regard. (You could look it up at
<<http://av-info.faa.gov/dst/amateur/8130.2chap4sec7.pdf>> Look for paragraph 134).
Here is a quote that, according to FAA Order 8130.2E, must be included in
each ABEA's Operating Limitations: "In addition, this aircraft must be operated
in accordance with applicable air traffic and general operating rules of part 91
and all additional limitations herein prescribed under the provisions of
91.319(e)."
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 modified for different control of PM alternator |
>Bob,
>
>The e-mail that the dwg was atch'd to had the "rational'
>The e-mail itself may seem a bit long but the key "concept" I'm trying to
>get critique on is this: The Z-13 "alternate alternator, the SD-8" was
>published using battery power to the OVM relay's coil (before start) and I
>simply changed that relay terminal's source of power from "battery" to
>"output of the PM alternator's VR itself" - no alternator output, no closing
>of the relay; or, if have output, and have DC master on (rewired to provide
>ground to PM alternator's OVMcoil's relay) then OVM relay closes, passing
>main alternator power on to main elec system at left side of Main or #1
>battery contactor.
Why is this necessary or useful?
>The switch to bypass a failed diode between main and E-busses is another
>issue, not very important, and not related to the wiring of the "single PM
>alternator" so it will be totally independent of BOTH, the battery (before
>start) and the #1/Main battery contactor (at all times after start and
>normal ops up until failure of batt contactor to 'open' state).
When was the last time you had a diode fail? You already have
an alternate feed path to back up a broken wire in the normal
feed-path, why a switch to back up a diode?
>I know you are busy - so just focus on the issue of how I've proposed wiring
>the PM alternator.
> - Somewhere down in the e-mail, I addressed an issue of "a CB taking a
>BIG slug of overvoltage & current" and, thereby, "welding" or "shorting" so
>it can't open.
Doesn't happen . . . breakers are tested for thousands
of trips with fault currents of up to 1000A . . . a breaker
so poorly designed as to suffer the condition you cited
is a dismal product.
> I am talking about the 5amp CB that the OVM module is
>supposed to pop when it senses an overvoltage. I am just asking if a
>"backup fuse" (which I believe doesn't have the physical capability of
>failing like the CB) would be a rational addition of redundancy/backup to
>the CB so the runaway alternator or its VR would be sure to be taken off
>line when the OVM shorts to initiate killing coil current in the OVM's relay
>so it will open and disconnect alternator from aircraft's system.
What leads you to believe that this operation isn't
well served with as-published architectures?
When you rewire the ov module as depicted, you depend on alternator
output to crowbar the breaker . . . the original design relies
on battery (MUCH better source of current) to crowbar
the breaker. Average fault current in the OVM is 300A
before the breaker opens in 5-10 milliseconds. We WANT
that much current to achieve the rapid disconnect. Your
alternator won't deliver enough current for reliable crowbar
operation. This system was tested at Beech 20+ years ago
for 50 faults in row with excellent results.
Obviously you can wire your airplane any way you wish. If you
have concerns about features in the published drawings, they
are easily mitigated or confirmed by analysis of simple ideas
upon which the design is based. I'm not saying the diagrams
are golden. I am suggesting that if are problems with the
drawings, they need to be fixed . . . not only for your
project but for thousands of other folks who possess the
drawings.
Given that both of your alternators are large (30+ amps)
let's take Figure Z-14. Tell us what concerns you have about
the details of this configuration and let's address them
individually to see if further evolution of the drawing
is called for.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Microprocessor based Fuel Gauge |
Linearizer
>
>I have heard that capacitive gages will not work with Jet-A because
>there is some water dissolved in the fuel which gives it some
>conductivity. You may be able to use insulated sensors.
There is a certain amount of water dissolved
in all fuels. Our bizjets all use capacity type
fuel gages.
Bob . . .
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
| Subject: | RE: Microprocessor based Fuel Gauge Linearizer |
Welcome back Bob.
There has been a lot of intelligent thought posting on this issue. Stuff of real
value. My feeling from all this is that the ideal would be some stone-simple
and reliable level measurement (even just a single-point) AND a totalizer. I
can't get real excited about the cork on the arm level-sensors.
There's always something new in liquid level sensing. Check these guys--
http://www.merl.com/papers/docs/TR2002-21.pdf Automatic sensing of liquid level in your beer glass in a restaurant!
or just do a Google search on "Liquid Level Sensing". What a dream world we live
in! Amazing!
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones(at)charter.net
"Better not take a dog on the Space Shuttle, because if he sticks his head out
the window when you're coming home....Oops!.".
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 mod'd by David Carter |
>
>
>Bob,
>
>My file size in My Documents shows 293KB. Also, when I reviewed the email
>with atch that I sent, the e-mail showed the atch as 299KB. I don't have a
>clue why it would show up as as 3 megabyte file.
I'm trying to figure that out. It was the .pdf file that jumped to
2.9 mbyte and took a very long time to compile. My original Z13
is 160 KB, when I print that to a .pdf file it comes out a respectable
124K. When I do a "select all" in the original, I get 850 entities
as reported by AutoCAD.
>About the 1700 entities - I searched Intellicad "Help" and couldn't find how
>to tell how many entities are in my drawing. It should be less than was in
>the Z-13 drawing I started with because I eliminated 2 mags, the "main"
>alternator & VR, a switch, and a few lines. There shouldn't be a big
>difference.
>
>I'll attach the file again. See if it looks more reasonable this time. If
>still goofed up, let me know "off list".
>
>I changed the dwg from "black background" with "white lines" to "white
>backgnd" with "black lines". Would that make a difference?
I'm mystified. What cad program are you using to edit the drawing?
Bob . . .
________________________________________________________________________________
| From: | "Wolfgang Trinks" <Wolfgang.Trinks(at)flugbereitschaft.com> |
| Subject: | Re: Microprocessor based Fuel Gauge Linearizer |
----- Original Message -----
From: "Tom Schiff" <tomschiff(at)attbi.com>
Subject: RE: AeroElectric-List: Microprocessor based Fuel Gauge Linearizer
>
> I have heard that capacitive gages will not work with Jet-A because
> there is some water dissolved in the fuel which gives it some
> conductivity. You may be able to use insulated sensors.
>
It is true that Jet-A1 has the capability of dissolving a limited amount of
water variing with its temperature. So does gasoline. Espacially AVGAS 100LL
is prone to that effect. This is one of the few drawbacks compared with
automotive fuel and its one of the reasons you have to strain your fuel
system before flight.
But dissolved water in that percentages possible has neglectible effect on
conductivity.
Capacitive fuel storage measurement is the one and only firstclass system
for the time beeing and its the system the vast majority of all jet-A
burning planes carry on board.
But there is a problem with water with some of this systems.
There are systems that do not measure absolute capacity of the probes but
compare it to a reference probe that is also installed in the fuel cell.
This ref-probe must be always submerged in fuel. So it is located on the
lowest position possible. Now if some of this dissolved water falls out of
the fuel due to reachnig the saturation point and collects as pure water it
will also move to this lowest location(its specific density is higher than
the fuels). If this water gets into this ref-capacitor it will srew up the
complete system. If a system has such trouble it either has not been
strained regulary or the strain system is a less than perfect design.
There might be a new kid on the block in a while. I have heard that the car
industry is working on a ultrasonic based system that is sending ultrasonic
sound waves into the fuel and is determing the damping of this sound energy
by the fuel mass contained in the cell.
They also have more and more problems with complex shaped fuel cells.
Wolfgang..
________________________________________________________________________________
aeroelectric-list(at)matronics.com
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Source for Pins & Extraction tools |
>Hi Bob,
>
>I don't know if you missed this post or not, but if you have any ideas I'd
>appreciate it.
>
>Thanks, Paul
I'm not sure but it sounds like you're dealing with the
high-density d-sub connectors. The 20AWG series are found
in MOST places on the back of your computer . . .
except for the video connector which is a 22AWG series
that puts 15 pins higher density into the 9-pin shell
of the lower density.
These are smaller pins do take a smaller extraction tool.
I've tested our 20AWG crimp tool for adequacy of crimp
on 22AWG pins but we don't stock an extraction tool. The
"el cheapo" extractor for these little pins is pretty
flimsy. I don't have a part number for it but there's a
really nice tool with interchangeable tips that handles
both the 20 and 22 AWG pins. It's AMP P/N 91285-1
Do a Google search on the 'net and you'll get a hundred
or so hits on sources/info about this tool.
Bob . . .
________________________________________________________________________________
aeroelectric-list(at)matronics.com
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Source for Pins & Extraction tools |
<5.0.0.25.2.20030521151305.01278dd0(at)pop.central.cox.net>
>Bob,
>
>The mystery is solved. I went to my avionics shop and he knew what they
>were. They are sockets for D style connectors and they are made by ITT, the
>nose is split and the barrel is very slightly smaller. They will only work
>with the ITT shell..
>
>He had some ITT sockets but he didn't really want to sell them to me, he
>said they we troublesome and he would prefer that I didn't use them. His
>recommendation was to discard the shell and get a new connector that takes
>the conventional sockets.
>
>Cheers, Paul
Oh yeah . . . I remember that. Seems that the shells are shorter
too . . .
I concur with his recommendation. Do you have a local source
for "plain vanilla" shells?
Bob . . .
________________________________________________________________________________
| From: | "Jon Finley" <jon(at)finleyweb.net> |
| Subject: | Group ExpressPCB Board Purchase? - EZ-Trim Altitude |
Hold
Hi all,
I am interesting in building (attempting to build!!) one of Cliff Cady's
Altitude hold units (http://members.aol.com/ccady/eztrim.htm). The
minimum order for these boards from ExpressPCB is 2 (~$45 per board).
I'm wondering if there is enough interest to order a batch of 10 or so
(~$14 per board).
If interested, please send me a message offline (jon(at)finleyweb.net)
indicating the number of boards you'd like. If enough interest is shown
I will privately contact each of you and get a firm commitment.
Thanks,
Jon Finley
N90MG Q2 - Subaru EJ-22 DD - 440 Hrs. TT - 0 Hrs Engine
Apple Valley, Minnesota
http://www.FinleyWeb.net/default.asp?id=96
________________________________________________________________________________
| From: | "Alex Peterson" <alexpeterson(at)usjet.net> |
| Subject: | 9th Annual Twin Cities RV Forum |
Greetings Listers,
Just a reminder that the 9th Annual Twin Cities RV Forum is just 10 days
away!! Fuel those RV's up and come up to the Minneapolis, Minnesota
area for a day of "RV Heaven". Rumor has it that a batch of RV's will
be coming in from Colorado, which is just a short hop or two from MN.
I'll bet there are some Texas or East Coast or West Coast planes that
want to grab the prize for longest distance. The Forum is May 31st, and
consists of many interesting speakers, vendors, RV's on display, door
prizes and much more. The evening banquet puts the finishing touches on
the day's events - don't miss the interesting evening talk by Bryan
Moon, a renowned MIA hunter who has brought back almost 40 WWII airmen
in many, many expeditions. Be sure to preregister if you plan to attend
the banquet.
For details, see www.rvforum.org.
Alex Peterson
Chairman, Twin Cities RV Forum
17650 82nd Way North
Maple Grove, Minnesota, 55311
612-418-9710
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 mod'd by David Carter |
<5.0.0.25.2.20030521190059.011d98b8(at)pop.central.cox.net>
>Yes, have DSL.
Try starting the CD Rom dowload late at night before
you go to bed. Tell your browser to store it to a directory
on your hard drive (right click the link) instead of letting
it try to work with the incoming file. The total file size
is about 200 Megabytes.
>What do you want me to do next? I was thinking of downloading Z13 from your
>site again and NOT changing backgnd from black to white (and lines from
>white to black) and just send it back and see it if will process through
>Adobe to a reasonable pdg file.
> - Maybe you could quickly try that same thing from your end - fresh
>download to hard drive, then process out thru Adobe to pdf and see if any
>glitches in original file that we all download.
We're getting the cart in front of the horse. Let's
not struggle with software integration issues until
we deduce what's bothering you about the details
of any of the architectures as published.
There's a lot we can do with words and grandpa's
PAD (pencil aided design) system and safe the
byte thrashing until you have a plan.
Bob . . .
________________________________________________________________________________
| From: | "Rick Fogerson" <rickf(at)cableone.net> |
| Subject: | Source and description of BNC and solder. |
Does anyone know of a source for solder type BNC connectors? My local Radio Shack
only had screw type and crimp type.
Solder: I have some "60/40 rosin core" type soldier. I suppose this stuff is
not recommended for electronics. If not, what should I get and where?
Thanks,
Rick Fogerson
RV3 finish kit
Boise, ID
________________________________________________________________________________
| Subject: | Re: Source and description of BNC and solder. |
In a message dated 5/22/2003 12:26:02 AM Eastern Standard Time,
rickf(at)cableone.net writes:
> Does anyone know of a source for solder type BNC connectors? My local
> Radio Shack only had screw type and crimp type.
>
> Solder: I have some "60/40 rosin core" type soldier. I suppose this stuff
> is not recommended for electronics. If not, what should I get and where?
>
> Thanks,
> Rick Fogerson
> RV3 finish kit
> Boise, ID
>
>
Rick, For RG-58 cable, solder/clamp connectors look at www.digikey.com part
number ARF1040-ND. Rosin core 60/40 will work fine. Installing these will be
the ultimate test of your patience and skill. Remove the jacket without
nicking any shielding wire strands, comb all shield strands out flat with no over
lapping ones, bend 90 degrees to cable, cut to 1/8" length in a perfect
circle. The center pin can best be soldered on by tinning the prepared length
of
center conductor wire first then prep the center pin with a drop of liquid flux,
put the center pin on the wire and touch with a hot freshly tinned soldering
iron tip for just a second. Assemble into plug.
You will need to practice for several cycles to get this right. Pay strict
attention to all measurements on the instruction sheet. On a scale of 1 to 10
this is a solid level 8 task to do perfectly. Have fun.
John P. Marzluf
Columbus, Ohio
Kitfox Outback (out back in the garage)
________________________________________________________________________________
| From: | "Dennis O'Connor" <doconnor(at)chartermi.net> |
| Subject: | Re: Source and description of BNC and solder. |
http://www.thewireman.com/connect5.html
Tell em Denny - K8DO, sent you and deserves a discount on his next order...
Denny
----- Original Message -----
From: "Rick Fogerson" <rickf(at)cableone.net>
Subject: AeroElectric-List: Source and description of BNC and solder.
>
> Does anyone know of a source for solder type BNC connectors? My local
Radio Shack only had screw type and crimp type.
>
> Solder: I have some "60/40 rosin core" type soldier. I suppose this
stuff is not recommended for electronics. If not, what should I get and
where?
>
> Thanks,
> Rick Fogerson
> RV3 finish kit
> Boise, ID
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Headphone noise on transmit |
>
>
>I've been fussing with what seemed to be ignition or alternator noise in
>my radio when I pushed the PTT on my Microair 760. I posted to the list a
>while back, and tried a different power source and a different
>antenna. The noise was there even when powered from a separate
>battery. Here is the thing: the noise is a loud hiss that I only hear
>when transmitting. Reception is clear as a bell. What I found out today
>is that my transmissions are clear as well. I spoke with another pilot
>sharing the pattern as we self-announced our way into Avon Park this
>morning and he said my signal was loud and clear, no hiss or any
>noise. It seems the noise is only coming out my headphones. I
>experimented and found the noise is independent of the radio volume but
>decreases if I turn down the headphones, so I can mitigate it somewhat by
>turning down the headphones and turning up the radio volume. These are
>twenty year old David Clark H10-80 'phones they don't make anymore. I
>haven't tried any others. That could they be the problem?
No . . . "hiss" is purely electronic. ALL amplifiers
in audio systems have some noise that is perceived
as hiss . . . the best are so low as to be undetectable
during normal operations. Are you using an intercom
system in addition to the 760VHF or are you using the
intercom built into the radio?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: sifting good stuff out of the noise |
>Bob,
> From your Ft. Worth seminar a few year's ago, my memory is fading a
>little. So I write to use you as a referee over different opinions I'm
>getting about my intentions for the electrics part of my IO-360A1D, to
>be installed on my Cozy MKIV. From your books and seminar I thought 1 RG
>battery, main alternator and one backup alternator, one electronic
>ignition and one mag. No vacuum pump - all electric avionics. Some folks
>recommend two batteries,
Good idea when you put the second electronic ignition in.
>others won't even mess with electronic ignition.
. . . that's their privilege.
>Some ask why even need a backup alternator. Perhaps cost is in their
>decisions, but cost isn't high on my list as long as I can minimize the
>chance that electrics won't be the cause of losing an engine or radios.
once you pull the vacuum pump off, you have an open hole
on the engine capable of holding an alternator that is lighter
and less expensive than the vacuum pump you took off. I wouldn't
fly MY airplane around with a wasted drive pad . . .
>(I'll be close to IFR capable, but day VFR will be my greatly preferred
>operation.) What say you about the above, and would you recommend another
>approach? Perhaps I'll attend another of your seminars, now that I am
>several steps closer to hooking things up. Thanks very much.
You're suffering from the OFATSULP syndrome . . . (Opinions
Founded on Anecdotes and Tradition Sans Understanding
of Logic or Physics). Opinions are a dime-a-dozen, some are even
free. Knowledge is also dirt cheap . . . it's all around us
just waiting to be picked up. Education is the hard part,
it takes time and consideration of how the pieces fit together.
Take all the advice "under advisement" . . . but join us
on the AeroElectric List where lots of studious folks will
help you sift the good stuff out of the sand and dust.
Which backup alternator did you buy and which power distribution
diagram is most attractive to you?
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | Finn Lassen <finnlassen(at)netzero.net> |
| Subject: | iPaq 3630 Pocket PC repair |
Anybody know where I can get the PCB connector to the display replaced
at a resonable price (less than $100)?
Or maybe just a source (and part number) for the connector?
It's the CN12 90-pin connector to the flat-ribbon cable going to the
display.
What kind of tool does one use to replace it? Some kind of hot-air gun?
Finn
Robert L. Nuckolls, III wrote:
>
>
>
>
>>Bob,
>>
>>
>
>
>
>>From your Ft. Worth seminar a few year's ago, my memory is fading a
>>little. So I write to use you as a referee over different opinions I'm
>>getting about my intentions for the electrics part of my IO-360A1D, to
>>be installed on my Cozy MKIV. From your books and seminar I thought 1 RG
>>battery, main alternator and one backup alternator, one electronic
>>ignition and one mag. No vacuum pump - all electric avionics. Some folks
>>recommend two batteries,
>>
>>
>
> Good idea when you put the second electronic ignition in.
>
>
>
>>others won't even mess with electronic ignition.
>>
>>
>
>
> . . . that's their privilege.
>
>
>
>>Some ask why even need a backup alternator. Perhaps cost is in their
>>decisions, but cost isn't high on my list as long as I can minimize the
>>chance that electrics won't be the cause of losing an engine or radios.
>>
>>
>
> once you pull the vacuum pump off, you have an open hole
> on the engine capable of holding an alternator that is lighter
> and less expensive than the vacuum pump you took off. I wouldn't
> fly MY airplane around with a wasted drive pad . . .
>
>
>
>>(I'll be close to IFR capable, but day VFR will be my greatly preferred
>>operation.) What say you about the above, and would you recommend another
>>approach? Perhaps I'll attend another of your seminars, now that I am
>>several steps closer to hooking things up. Thanks very much.
>>
>>
>
> You're suffering from the OFATSULP syndrome . . . (Opinions
> Founded on Anecdotes and Tradition Sans Understanding
> of Logic or Physics). Opinions are a dime-a-dozen, some are even
> free. Knowledge is also dirt cheap . . . it's all around us
> just waiting to be picked up. Education is the hard part,
> it takes time and consideration of how the pieces fit together.
> Take all the advice "under advisement" . . . but join us
> on the AeroElectric List where lots of studious folks will
> help you sift the good stuff out of the sand and dust.
>
> Which backup alternator did you buy and which power distribution
> diagram is most attractive to you?
>
> Bob . . .
>
> --------------------------------------------
> ( Knowing about a thing is different than )
> ( understanding it. One can know a lot )
> ( and still understand nothing. )
> ( C.F. Kettering )
> --------------------------------------------
>
>
>
>
________________________________________________________________________________
| Subject: | Re: sifting good stuff out of the noise |
Bob coins a new aviation acronym:
<
Dan
________________________________________________________________________________
| Subject: | Source and description of BNC and solder. |
Try...
www.mcmelectronics.com
Chris Stone
RV-8 Wings
-----Original Message-----
From: Rick Fogerson [mailto:rickf(at)cableone.net]
Subject: AeroElectric-List: Source and description of BNC and solder.
-->
Does anyone know of a source for solder type BNC connectors? My local
Radio Shack only had screw type and crimp type.
Solder: I have some "60/40 rosin core" type soldier. I suppose this
stuff is not recommended for electronics. If not, what should I get and
where?
Thanks,
Rick Fogerson
RV3 finish kit
Boise, ID
direct advertising on the Matronics Forums.
________________________________________________________________________________
| From: | "Wolfgang Trinks" <Wolfgang.Trinks(at)flugbereitschaft.com> |
| Subject: | Re: LOM OVP System |
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: LOM OVP System
>
> >
> >
> >Hello Bob,
> >
>
>
>
>
> >So looking at your drawing Z-18 raises a question of what I wood be
> >interested in your opinion:
> >
> >Would it be ok related to the failure scenarios of a mechanical regulator
to
> >only use the GENERATOR FIELD DISCONNECT RELAY to cut the field in an
> >OVP-event and to rely on the reverse current cuttoff relay consisted in
the
> >regulator to disconnect the D+ line from the B+ line due to the resulting
> >breakdown of the generator output?
>
> I guess it depends on the failure mode. Not having intimate
> details on the construction of the regulator, I cannot
> deduce failure modes and behavior in modes unique to
> that product.
>
>
> >Do you have experience with this LUN regulator?
>
> No.
>
> >I have studied the little scematic in the cap and came to the opinion
that
> >it is a 3 point type (cutout, voltage and current) where 2 contacts(
cutout
> >and current) are located on one coil core.
>
> Interesting . . . I'm having trouble figuring out how that works.
Normally
> a current limit contactor closes on decrease of magnetic field while a
> cutout contact closes on increase of magnetic field. I can sorta see
> how you might be clever and design both current and voltage limits
> onto the same coil reverse current on the other . . .
>
I will explain my assumptions. For that I have put a picture with 3 figures
of the schematic of the regulatur in the photoshare list. Title: LUN
Regulator. Up to it is not availible yet. As soon as it shows up ill do.
I am in vacation now till 1. of june
Wolfgang
> >I have to admit that I do not fully understand the functionality of the
PR
> >pin. It seems to me to be a potential paralleling in/output for a
> >2-Generator system.
>
>
> That's HAS been done so your suggestion is not unreasonable
>
> >Nevertheless I have meassured that it is normally open and if the cutout
> >relay is connecting the generator voltage shows up there after passing a
> >coil on the voltage relay.
>
>
> >If one knew the effects on the voltage regulation( so to avoid influance
> >there) it would be a positive possible indication for generator operation
> >because it shows the state of the cutout relay.
>
> The most common failure I've seen in electro-mechanical regulators
> to create and ov condition is broken wire on the voltage control
> coil. Of course, breaking the field lead will mitigate the ov
> condition. My reasoning for opening this one lead was that should
> the reverse current cutout be stuck shut as well, the upstream
> protection (fusible link, breaker or fuse) would open due to high
> value of current flowing back into the generator.
>
> One could make the ov relay a two-pole device to open BOTH
> field and output leads . . . be sure to do BOTH. If you open
> only the output lead, the ov condition will continue on the
> generator and it will happily commit suicide by burning up
> it's own field windings.
>
> You could also consider a faster acting output protection like
> a fuse . . . it can be pretty large compared to generator output
> 'cause the overload will be severe if the field lead is opended
> and the reverse current relay in the regulator doesn't react
> properly.
>
> Welcome to the Aero-Electric List. Hope you'll hang around
> an participate in some really cool discussions.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: sifting good stuff out of the noise |
>
>Bob coins a new aviation acronym:
>
><Understanding of Logic or Physics)
>
> I love it! However, it will probably get you punched in a fly-in
> debate;
>"Hey buddy, I think you have o-fat-slup"
Sounds good to me . . . suppose we can get it added to the
the glossary of alphanumerical secret codes in the FAR/AIM?
Bob . . .
________________________________________________________________________________
| Subject: | Any standard for keyswitch orientation ? |
Hi all,
Is there a commonly accepted standard or trend for the mag keyswitch
orientation on the panel ?
I mean, for instance key entry at 10 o'clock, and 'BOTH' position at 2
o'clock or else.
We were having a discussion on the subject, and when the question arose I
got stuck.
Thanks for any input,
Regards,
Gilles
________________________________________________________________________________
| From: | "David Swartzendruber" <dswartzendruber(at)earthlink.net> |
| Subject: | Any standard for keyswitch orientation ? |
I don't know if it's a standard, but the current production Cessna
Singles have the off position at 10 o'clock, R at 11 o'clock, L at 12
o'clock, BOTH at 1 o'clock and START at 2 o'clock.
Dave in Wichita
> Is there a commonly accepted standard or trend for the mag keyswitch
> orientation on the panel ?
> I mean, for instance key entry at 10 o'clock, and 'BOTH' position at 2
> o'clock or else.
>
> Regards,
>
> Gilles
________________________________________________________________________________
| Subject: | iPaq 3630 Pocket PC repair |
| From: | "Don Honabach" <don(at)pcperfect.com> |
>> What kind of tool does one use to replace it? Some kind of hot-air
gun?
If the connector is surface mounted, you'll want to practice on some
spare PCBs with surface mounts connectors/components first. Took me
about 5 or so boards before I could do an acceptable job for surface
mount ICs and connectors.
The connectors can be removed using a special solder that has low
melting point and seems to grab the existing solder holding the
component/connector on the board (don't remember the name of the stuff
off hand, but if needed, send me an e-mail).
Installation requires lots of patience, a small soldering iron/tip, and
it goes a lot quicker with solder paste but can be done with small sized
solder as well. I find the solder paste works better because you can
just run a line of solder paste on the PCB's connector pads and then run
the solder iron down the same line. The solder paste will then work
itself onto the PAD areas when heated. As long as you don't over due it,
you can solder lots of 'pins' this way very quickly versus the one by
one method required with normal solder.
Good Luck,
Don Honabach
Tempe, AZ - Zodiac 601HDS
-----Original Message-----
From: Finn Lassen [mailto:finnlassen(at)netzero.net]
Subject: AeroElectric-List: iPaq 3630 Pocket PC repair
-->
Anybody know where I can get the PCB connector to the display replaced
at a resonable price (less than $100)?
Or maybe just a source (and part number) for the connector? It's the
CN12 90-pin connector to the flat-ribbon cable going to the
display.
What kind of tool does one use to replace it? Some kind of hot-air gun?
Finn
Robert L. Nuckolls, III wrote:
>-->
>
>
>
>
>>Bob,
>>
>>
>
>
>
>>From your Ft. Worth seminar a few year's ago, my memory is fading a
>>little. So I write to use you as a referee over different opinions I'm
>>getting about my intentions for the electrics part of my IO-360A1D, to
>>be installed on my Cozy MKIV. From your books and seminar I thought 1
>>RG battery, main alternator and one backup alternator, one electronic
>>ignition and one mag. No vacuum pump - all electric avionics. Some
>>folks recommend two batteries,
>>
>>
>
> Good idea when you put the second electronic ignition in.
>
>
>
>>others won't even mess with electronic ignition.
>>
>>
>
>
> . . . that's their privilege.
>
>
>
>>Some ask why even need a backup alternator. Perhaps cost is in their
>>decisions, but cost isn't high on my list as long as I can minimize
>>the chance that electrics won't be the cause of losing an engine or
>>radios.
>>
>>
>
> once you pull the vacuum pump off, you have an open hole
> on the engine capable of holding an alternator that is lighter
> and less expensive than the vacuum pump you took off. I wouldn't
> fly MY airplane around with a wasted drive pad . . .
>
>
>
>>(I'll be close to IFR capable, but day VFR will be my greatly
>>preferred
>>operation.) What say you about the above, and would you recommend
another
>>approach? Perhaps I'll attend another of your seminars, now that I am
>>several steps closer to hooking things up. Thanks very much.
>>
>>
>
> You're suffering from the OFATSULP syndrome . . . (Opinions
> Founded on Anecdotes and Tradition Sans Understanding
> of Logic or Physics). Opinions are a dime-a-dozen, some are even
> free. Knowledge is also dirt cheap . . . it's all around us
> just waiting to be picked up. Education is the hard part,
> it takes time and consideration of how the pieces fit together.
> Take all the advice "under advisement" . . . but join us
> on the AeroElectric List where lots of studious folks will
> help you sift the good stuff out of the sand and dust.
>
> Which backup alternator did you buy and which power distribution
> diagram is most attractive to you?
>
> Bob . . .
>
> --------------------------------------------
> ( Knowing about a thing is different than )
> ( understanding it. One can know a lot )
> ( and still understand nothing. )
> ( C.F. Kettering )
> --------------------------------------------
>
>
>
>
direct advertising on the Matronics Forums.
________________________________________________________________________________
Bob Could you explain why Z15B is not a good Idea.=A0=A0=A0 That particular
architecture would work well for the velocity where the #2AWG runs in a duct from
firewall through canard bulkhead right to the batteries. A seperate # 4AWG could
come from the panel ground block on the panel and to the batteries via a
different route.=A0 If you dont recommend this then I would have to cut through
the
duct inside the cabin behind the panel run the #2 wire up to the panel ground
presumable on the panel and then back down into the duct to go to the battery.
It would be a lot of heavy wire inside the cabin and onto the panel.=A0 Is there
a better way I'm not seeing?=A0=A0=A0=A0 Thanks Tim
________________________________________________________________________________
| From: | Duncan McBride <duncanmcbride(at)comcast.net> |
| Subject: | Re: Headphone noise on transmit |
I'm using a Sigtronics Transcom II that I mounted permanently to the panel.
It just came back from Sigtronics where they fixed a loose squelch knob and
converted it to the high noise version. It works great. The intercom's mic
hi wire is connected to the 760 mic hi pin. On the intercom the mic low and
headphone low are the coax shields to the plugs and are both grounded
together inside the intercom, so I just connected one of the coax shields on
the cable to the 760 mic lo pin. The intercom headphone hi is connected to
both the pilot and copilot headphone pins on the 760.
I say hiss, but it isn't like the white noise hiss you can hear in
electronic equipment - at least it seems so to me. It is a sharp rasp that
is directly related to engine rpm in pitch and intensity. At idle it is
noticeable but tolerable - at 5000 rpm (Rotax 912) it is loud enough that it
is difficult to hear yourself. I was afraid that's how it sounded to
others, but it seems the noise isn't getting out, and is heard only in the
headphones. It is weird - when I turn down the headphone volume control the
noise is diminished, but adjusting the volume on the 760 doesn't affect it.
It just occurred to me to turn the 760 volume down all the way, key the PTT
and see if I hear the noise. I'll test that next time.
This is exactly the same set of symptoms as when the Transcom was not
installed, so I don't think the intercom is a factor. Also, it wasn't
turned on when I experienced the symptoms described above. The Transcom is
not hooked up to the airplane power either, I'm still using the internal
9-volt battery for now.
Thanks for your patience trying to diagnose problems like this at a
distance. I was relieved to hear that my transmissions are clear to other
traffic, so now this is less a problem than a nuisance, but if anything
occurs to you that would help me zero in on the cause of the noise, I'd be
grateful.
Duncan
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: Headphone noise on transmit
>
> >
> >
> >I've been fussing with what seemed to be ignition or alternator noise in
> >my radio when I pushed the PTT on my Microair 760. I posted to the list
a
> >while back, and tried a different power source and a different
> >antenna. The noise was there even when powered from a separate
> >battery. Here is the thing: the noise is a loud hiss that I only hear
> >when transmitting. Reception is clear as a bell. What I found out today
> >is that my transmissions are clear as well. I spoke with another pilot
> >sharing the pattern as we self-announced our way into Avon Park this
> >morning and he said my signal was loud and clear, no hiss or any
> >noise. It seems the noise is only coming out my headphones. I
> >experimented and found the noise is independent of the radio volume but
> >decreases if I turn down the headphones, so I can mitigate it somewhat by
> >turning down the headphones and turning up the radio volume. These are
> >twenty year old David Clark H10-80 'phones they don't make anymore. I
> >haven't tried any others. That could they be the problem?
>
>
> No . . . "hiss" is purely electronic. ALL amplifiers
> in audio systems have some noise that is perceived
> as hiss . . . the best are so low as to be undetectable
> during normal operations. Are you using an intercom
> system in addition to the 760VHF or are you using the
> intercom built into the radio?
>
> Bob . . .
>
>
________________________________________________________________________________
| Subject: | MCR 4S fwing and flap system |
Hi all,
For those interested in learning more about our project, I posted an article
from Pilot magazine at the following URL :
http://gilles.thesee.free.fr/temp/Pilot100Yrs-06-164.pdf
It describes the design of the wing and flaps of the MCR 4S.
We're building the rotax 914 version.
Regards,
Gilles
________________________________________________________________________________
| From: | "Richard V. Reynolds" <rvreynolds(at)macs.net> |
| Subject: | Stick It-Your-Ear Headsets |
Does anyone have experience with either the
Panther CAT in-the-ear headset
Quiet Technology AuriComm in-the-ear headset
Richard Reynolds
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Stick It-Your-Ear Headsets |
In a message dated 5/23/03 9:32:36 AM Central Daylight Time,
rvreynolds(at)macs.net writes:
> Does anyone have experience with either the
>
> Panther CAT in-the-ear headset
>
> Quiet Technology AuriComm in-the-ear headset
>
> Richard Reynolds
>
Good Morning Richard,
Can you supply a site at which they might be viewed?
Happy Skies,
Old Bob
________________________________________________________________________________
| From: | Carlos Sa <carlosfsa(at)yahoo.com> |
| Subject: | Re: Stick It-Your-Ear Headsets |
http://www.quiettechnologies.com/index_004.htm
> > Does anyone have experience with either the
> >
> > Panther CAT in-the-ear headset
> >
> > Quiet Technology AuriComm in-the-ear headset
> >
> > Richard Reynolds
> >
> Good Morning Richard,
>
> Can you supply a site at which they might be viewed?
>
> Happy Skies,
>
> Old Bob
________________________________________________________________________________
| From: | Carlos Sa <carlosfsa(at)yahoo.com> |
| Subject: | Re: Stick It-Your-Ear Headsets |
This is the main URL (the previous one was for just one frame)
http://www.quiettechnologies.com/
> > Does anyone have experience with either the
> >
> > Panther CAT in-the-ear headset
> >
> > Quiet Technology AuriComm in-the-ear headset
> >
> > Richard Reynolds
> >
> Good Morning Richard,
>
> Can you supply a site at which they might be viewed?
>
> Happy Skies,
>
> Old Bob
________________________________________________________________________________
| From: | Charles Brame <charleyb(at)earthlink.net> |
| Subject: | 90 degree BNC Connectors |
90 degree BNC Connectors would make my antenna connections easier and
more hidden.
Do such critters exist?
Is there a reasonable source for 90 connectors?
Any pros or cons to their use?
Charlie
RV-6A N11CB
San Antonio
________________________________________________________________________________
| From: | Melvinke(at)aol.com |
| Subject: | Re: Stick It-Your-Ear Headsets |
Having both Bose and Lightspeed noisecancelling headsets, and doubting that
anything could be better, I was surprised and delighted to find the Panther
unit even better, and certainly more comfortable. No more losing the headset with
aerobatics and other higher G maneuvers. I personally prefer the Panther to
anything else I have tried.
Kenneth Melvin
RV4
________________________________________________________________________________
| Subject: | Re: 90 degree BNC Connectors |
Charlie,
I asked the same question a few months back. There are a few expensive
ones. None seem to be crimp-on. The easy way is a 90 degree male-female BNC
adapter from Radio Shack.
Dan
________________________________________________________________________________
| Subject: | 90 degree BNC Connectors |
Try:
www.pasternack.com/pdf/parts/pe9085.pdf
Or
www.pasternack.com
Products
Adapters
BNC male
BNC female
You should see a list of various BNC adapters including 90
Chris Stone
RV-8 Wings
-----Original Message-----
From: Charles Brame [mailto:charleyb(at)earthlink.net]
Subject: AeroElectric-List: 90 degree BNC Connectors
-->
90 degree BNC Connectors would make my antenna connections easier and more hidden.
Do such critters exist?
Is there a reasonable source for 90 connectors?
Any pros or cons to their use?
Charlie
RV-6A N11CB
San Antonio
________________________________________________________________________________
| From: | MikeM <mladejov(at)ced.utah.edu> |
| Subject: | Re: AeroElectric-List Digest: 15 Msgs - 05/22/03 |
> From: Duncan McBride <duncanmcbride(at)comcast.net>
> Subject: Re: AeroElectric-List: Headphone noise on transmit
> .....
> but if anything
> occurs to you that would help me zero in on the cause of the noise, I'd be
> grateful.
>
> Duncan
Duncan,
When you wired you PTT switch, where did you ground it? It
should be grounded at the same place your COM is grounded,
not to some other place in the airframe...
MikeM
________________________________________________________________________________
| Subject: | Alternator Repair |
| From: | Tom Nalevanko <tom(at)websiteasp.com> |
Our EAA Chapter 723 in Camarillo, CA has been donated an older Sears
Model No. 580.326010, 4500 Watt Heavy Duty Portable Alternator. When
started, the gas engine runs great but the voltage from the 120VAC
outlet is only 12 VAC (low by a factor of 10). My suspicion is that the
Voltage Regulator (a solid state "voltage over frequency" regulator)
which is inline with the Rotor Field Winding is defective. A new one
costs about $200 with tax and shipping. As you may know, EAAsters avoid
spending $$$ on non-flying stuff unless absolutely necessary.
Does anyone have any ideas on this? Does my suspected cause sound
reasonable? Any ideas whether the voltage regulator might be available
other than thru Sears? The voltage regulator has a 6 conductor plug.
Any help would be appreciated.
Blue skies,
Tom
________________________________________________________________________________
| Subject: | Re: Any standard for keyswitch orientation ? |
----- Message d'origine -----
De : "David Swartzendruber"
:
Envoy : jeudi 22 mai 2003 20:54
Objet : RE: AeroElectric-List: Any standard for keyswitch orientation ?
>
> I don't know if it's a standard, but the current production Cessna
> Singles have the off position at 10 o'clock, R at 11 o'clock, L at 12
> o'clock, BOTH at 1 o'clock and START at 2 o'clock.
>
> Dave in Wichita
Dave,
Thanks for the info.
Gilles
________________________________________________________________________________
| Subject: | Re: AeroElectric-List Digest: 15 Msgs - |
05/22/03
This brings up a question I have been thinking about for a while now and
that is, Isnt ground, ground? In the case of a metal airplane the whole
thing is a ground. How does it matter where things are grounded? Isnt it
all the same?
>
>> From: Duncan McBride <duncanmcbride(at)comcast.net>
>> Subject: Re: AeroElectric-List: Headphone noise on transmit
>> .....
>> but if anything
>> occurs to you that would help me zero in on the cause of the noise, I'd be
>> grateful.
>>
>> Duncan
>
>Duncan,
>
>When you wired you PTT switch, where did you ground it? It
>should be grounded at the same place your COM is grounded,
>not to some other place in the airframe...
>
>MikeM
>
>
Scott Bilinski
Eng dept 305
Phone (858) 657-2536
Pager (858) 502-5190
________________________________________________________________________________
| Subject: | Re: AeroElectric-List Digest: 15 Msgs - 05/22/03 |
| From: | "Don Honabach" <don(at)pcperfect.com> |
Scott,
>> Isnt ground, ground?
I'm sure Bob has a better answer to this, but if I understand things
properly having a common ground point for all devices can help minimize
problems with more sensitive devices that tend to be affected by noise
and/or by ground loop issues.
For a poor analogy, aren't all women the same? The answer to many is
yes, but experience has taught us that being 'connected' to many women
can lead to problems (smile).
Regards,
Don
-----Original Message-----
From: Scott Bilinski [mailto:bilinski@kyocera-wireless.com]
Subject: Re: AeroElectric-List: Re: AeroElectric-List Digest: 15 Msgs -
05/22/03
--> <bilinski@kyocera-wireless.com>
This brings up a question I have been thinking about for a while now and
that is, Isnt ground, ground? In the case of a metal airplane the whole
thing is a ground. How does it matter where things are grounded? Isnt it
all the same?
>
>> From: Duncan McBride <duncanmcbride(at)comcast.net>
>> Subject: Re: AeroElectric-List: Headphone noise on transmit .....
>> but if anything
>> occurs to you that would help me zero in on the cause of the noise,
I'd be
>> grateful.
>>
>> Duncan
>
>Duncan,
>
>When you wired you PTT switch, where did you ground it? It should be
>grounded at the same place your COM is grounded, not to some other
>place in the airframe...
>
>MikeM
>
>
Scott Bilinski
Eng dept 305
Phone (858) 657-2536
Pager (858) 502-5190
direct advertising on the Matronics Forums.
________________________________________________________________________________
| From: | RSwanson <rswan19(at)comcast.net> |
| Subject: | Re: Alternator Repair |
I had a very similar situation with a generator that had not been used in a
while. I talked to a man at an electric shop and he said to wire a light
bulb in series with two male plugs, start the generator, plug one end in
the generator and the other to an AC plug. He said it would blow the
bulb, but fix the problem. Believe it not it worked, until it was started
again and it was like it was before the bulb treatment. I did some trouble
shooting with the generator running. This particular generator also puts
out 14 v. dc. While I was checking I accidentally shorted the 14 v.
positive to the ac terminal. The engine speed went down from the load, and
I figured 'great, probably smoked the whole thing', but no, it works
perfectly. My son has it now and if it's not used often, you have to short
the 14 v positive to the ac terminal and it works great. Don't ask me what
it 's doing, I just telling you the results.
R
----- Original Message -----
From: "Tom Nalevanko" <tom(at)websiteasp.com>
Subject: AeroElectric-List: Alternator Repair
>
> Our EAA Chapter 723 in Camarillo, CA has been donated an older Sears
> Model No. 580.326010, 4500 Watt Heavy Duty Portable Alternator. When
> started, the gas engine runs great but the voltage from the 120VAC
> outlet is only 12 VAC (low by a factor of 10). My suspicion is that the
> Voltage Regulator (a solid state "voltage over frequency" regulator)
> which is inline with the Rotor Field Winding is defective. A new one
> costs about $200 with tax and shipping. As you may know, EAAsters avoid
> spending $$$ on non-flying stuff unless absolutely necessary.
>
> Does anyone have any ideas on this? Does my suspected cause sound
> reasonable? Any ideas whether the voltage regulator might be available
> other than thru Sears? The voltage regulator has a 6 conductor plug.
>
> Any help would be appreciated.
>
> Blue skies,
>
> Tom
>
>
________________________________________________________________________________
| From: | Canyon <steve.canyon(at)verizon.net> |
| Subject: | RFI and Grounds... |
Scott Bilinski wrote:
>This brings up a question I have been thinking about for a while now and
>that is, Isnt ground, ground? In the case of a metal airplane the whole
>thing is a ground. How does it matter where things are grounded? Isnt it
>all the same?
---
Not trying to play games here -- simply proposing a couple things to
ponder. I have trained many ETs through the years and their training
all started with a couple simple ideas to ponder.
1. Is there any such thing as a short circuit?
2. Can two wires occupying the same physical space and carrying equal
currents of opposite polarity radiate energy externally?
Think about it and when you answer, I'll gauge your expertise from your
answer and elaborate appropriately when I can get a little more time to
be complete. Real short of time for the next few hours. :-)
Steve
________________________________________________________________________________
| From: | Duncan McBride <duncanmcbride(at)comcast.net> |
| Subject: | Re: AeroElectric-List Digest: 15 Msgs - 05/22/03 |
It is grounded at the same panel ground as the 760 COM - an AN3 bolt that
connects all the ground lines to an AWG 16 wire directly to the battery -
the battery is in the nose for balance so it's a short line.
----- Original Message -----
From: "MikeM" <mladejov(at)ced.utah.edu>
Subject: AeroElectric-List: Re: AeroElectric-List Digest: 15 Msgs - 05/22/03
>
> > From: Duncan McBride <duncanmcbride(at)comcast.net>
> > Subject: Re: AeroElectric-List: Headphone noise on transmit
> > .....
> > but if anything
> > occurs to you that would help me zero in on the cause of the noise, I'd
be
> > grateful.
> >
> > Duncan
>
> Duncan,
>
> When you wired you PTT switch, where did you ground it? It
> should be grounded at the same place your COM is grounded,
> not to some other place in the airframe...
>
> MikeM
>
>
________________________________________________________________________________
| From: | Duncan McBride <duncanmcbride(at)comcast.net> |
| Subject: | Re: AeroElectric-List Digest: 15 Msgs - 05/22/03 |
You are a perfect candidate for the Book. See http://www.aeroelectric.com/
and buy Bob Nuckoll's book. It has answered a hundred questions such as
yours, and knowing it's on the shelf makes me feel a little less guilty for
the help I get on this list.
----- Original Message -----
From: "Scott Bilinski" <bilinski@kyocera-wireless.com>
Subject: Re: AeroElectric-List: Re: AeroElectric-List Digest: 15 Msgs -
05/22/03
<bilinski@kyocera-wireless.com>
>
> This brings up a question I have been thinking about for a while now and
> that is, Isnt ground, ground? In the case of a metal airplane the whole
> thing is a ground. How does it matter where things are grounded? Isnt it
> all the same?
>
>
> >
> >> From: Duncan McBride <duncanmcbride(at)comcast.net>
> >> Subject: Re: AeroElectric-List: Headphone noise on transmit
> >> .....
> >> but if anything
> >> occurs to you that would help me zero in on the cause of the noise, I'd
be
> >> grateful.
> >>
> >> Duncan
> >
> >Duncan,
> >
> >When you wired you PTT switch, where did you ground it? It
> >should be grounded at the same place your COM is grounded,
> >not to some other place in the airframe...
> >
> >MikeM
> >
> >
>
>
> Scott Bilinski
> Eng dept 305
> Phone (858) 657-2536
> Pager (858) 502-5190
>
>
________________________________________________________________________________
| From: | Richard Tasker <retasker(at)optonline.net> |
| Subject: | Re: RFI and Grounds... |
What is your definition of a "short circuit"?
Two wires cannot occupy the same physical space in our universe, so what
do you really mean?
Canyon wrote:
>
>Scott Bilinski wrote:
>
>
>>This brings up a question I have been thinking about for a while now and
>>that is, Isnt ground, ground? In the case of a metal airplane the whole
>>thing is a ground. How does it matter where things are grounded? Isnt it
>>all the same?
>>
>>
>---
>Not trying to play games here -- simply proposing a couple things to
>ponder. I have trained many ETs through the years and their training
>all started with a couple simple ideas to ponder.
>
>1. Is there any such thing as a short circuit?
>
>2. Can two wires occupying the same physical space and carrying equal
>currents of opposite polarity radiate energy externally?
>
>Think about it and when you answer, I'll gauge your expertise from your
>answer and elaborate appropriately when I can get a little more time to
>be complete. Real short of time for the next few hours. :-)
>
>Steve
>
>
>
>
________________________________________________________________________________
| From: | "Tom..." <tsled(at)pacbell.net> |
| Subject: | RFI and Grounds... |
Heya Steve,
Oh yes! Set a pair of your old pliers across the terminals of your car
battery and you will have a full understanding of what a short is and what
one can do.
Tom...
>1. Is there any such thing as a short circuit?
>Steve
________________________________________________________________________________
| From: | "Rick Fogerson" <rickf(at)cableone.net> |
| Subject: | Electric Bob-Battery Contacter and Relay Questions |
Hi Bob,
Re the B&C battery contactor: Your wiring diagrams seem to indicate that a diode
goes between the Battery post and the smaller terminal closest to it. My contactors
actually have a plain wire jumper between the Battery post and the smaller
terminal closest to it and the diode wired between the two small terminals.
Is is this correct?
Re the S704-1 relay (used to switch power for >7A power when batterys are located
in the rear): Does it matter which one of the two solenoid terminals that
power is hooked to? The one closest to the com terminal or the one below it?
Also, your wiring diagram for the relays shows the NO terminal jumpered to a solenoid
terminal and the two solenoid terminals connected with a 1N4005 diode.
Are these external jumpers and diodes that I have to add or are these internal
to the relay?
Thanks,
Rick Fogerson
________________________________________________________________________________
| From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
-->
90 degree BNC Connectors would make my antenna connections easier and more
hidden. Do such critters exist? Is there a reasonable source for 90
connectors?Any pros or cons to their use?
Charlie RV-6A N11CBSan Antonio"
Remember, Charlie,
No offence, but if you're not familiar with coaxial cable
and its connectors,
[a] You are interested in 50 ohm connectors only, to match cable,[b]
Your primary cable is RG58, RG 400 or similar (for size), and
[c] You may want to study and practice attaching connectors to coax cable
because (1) it's not simple, and (2) 95% of antenna trouble is found in the
connectors, especially after a while unles properly done.
Happy hunting,
Ferg
Europa A064
________________________________________________________________________________
| From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
| Subject: | Ground is ground? |
<bilinski@kyocera-wireless.com>>
> This brings up a question I have been thinking about for a while now and>
that is, Isnt ground, ground?"
Scott,
The simple answer is "No, it's not".
"In the case of a metal airplane the whole> thing is a ground. How does it
matter where things are grounded? Isnt it> all the same?"
The ideal answer is:
You are a perfect candidate for the Book. See http://www.aeroelectric.com/
and buy Bob Nuckoll's book. It has answered a hundred questions such as
yours, and knowing it's on the shelf makes me feel a little less guilty for
the help I get on this list"
Happy Landings,
Ferg
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Electric Bob-Battery Contacter and |
Relay Questions
>
>Hi Bob,
>Re the B&C battery contactor: Your wiring diagrams seem to indicate that a
>diode goes between the Battery post and the smaller terminal closest to
>it. My contactors actually have a plain wire jumper between the Battery
>post and the smaller terminal closest to it and the diode wired between
>the two small terminals. Is is this correct?
see
http://www.aeroelectric.com/Catalog/switch/switch.html#s701-1
and
http://www.aeroelectric.com/Catalog/switch/s701-1l.jpg
>Re the S704-1 relay (used to switch power for >7A power when batterys are
>located in the rear): Does it matter which one of the two solenoid
>terminals that power is hooked to? The one closest to the com terminal or
>the one below it?
no
>Also, your wiring diagram for the relays shows the NO terminal jumpered to
>a solenoid terminal and the two solenoid terminals connected with a 1N4005
>diode. Are these external jumpers and diodes that I have to add or are
>these internal to the relay?
they are external See http://www.aeroelectric.com/articles/s704inst.jpg
Bob . . .
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
1) Along with keyswitch orientation. How about the little keyway on the toggle
switch bushing. I always put them on the OFF/Down side. Is there a standard I
don't know about?
2) Is there anyone kind enough to send me a copy of DO-160. I don't have the membership
dues right now but I promise to join when I can.
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones(at)charter.net
"Mankind faces a cross-roads. One path leads to despair and utter hopelessness.
The other, to total extinction. Let us pray we have the wisdom to choose correctly."
--Woody Allen
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: RFI and Grounds... |
>
>Scott Bilinski wrote:
> >This brings up a question I have been thinking about for a while now and
> >that is, Isnt ground, ground? In the case of a metal airplane the whole
> >thing is a ground. How does it matter where things are grounded? Isnt it
> >all the same?
>---
>Not trying to play games here -- simply proposing a couple things to
>ponder. I have trained many ETs through the years and their training
>all started with a couple simple ideas to ponder.
>
>1. Is there any such thing as a short circuit?
This is a common term in the vernacular of many
disciplines. In the airplane business, it's more often
referred to has a "hard fault" . . . but irrespective
of vernacular and venue it's understood to be an
unwanted conduction path producing current flows in
potentially hazardous ways. They often exceed the
path's rated current capability by many times.
A hard fault on a bizjet's ni-cad can get you several
thousands of amps "short circuit", "hard fault" or any
thing else one chooses to call it.
The only limitation on potential current flow in a
hard fault are path resistances which cannot be
(except in a super conduction environment) zero
ohms. 2,000A from a 24V battery suggests a path
resistance of 12 milliohms which has to include
internal resistance of the battery and all other
conductors (including ground) that are part of
the closed loop.
>2. Can two wires occupying the same physical space and carrying equal
>currents of opposite polarity radiate energy externally?
A theoretical hypothesis at best but assuming you could twist
a couple of 80AWG wires together without breaking them and
drive them as closed loop, the magnetic field around
the pair would be exceedingly low . . . but probably
not zero.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Two questions-- |
>
>1) Along with keyswitch orientation. How about the little keyway on the
>toggle switch bushing. I always put them on the OFF/Down side. Is there a
>standard I don't know about?
Our diagram numbers assume key-way up. Of course, this only affects
the progressive transfer switches. All others are mirror image
for operation and can mount either way.
>2) Is there anyone kind enough to send me a copy of DO-160. I don't have
>the membership dues right now but I promise to join when I can.
DO-160 is a 3-ring binder of some magnitude . . . it's
several hundred pages I think. I'm trying to track down
a .pdf version but no luck so far.
Bob . . .
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: Two questions-- |
In a message dated 5/25/03 12:19:29 AM Central Daylight Time,
bob.nuckolls(at)cox.net writes:
> >1) Along with keyswitch orientation. How about the little keyway on the
> >toggle switch bushing. I always put them on the OFF/Down side. Is there a
> >standard I don't know about?
>
> Our diagram numbers assume key-way up. Of course, this only affects
> the progressive transfer switches. All others are mirror image
> for operation and can mount either way.
>
Good Morning Bob and Eric,
For What It's Worth, in order to have the numbers right side up when using
Klixon CBs, the keyway must be up.
Happy Skies,
Old Bob
________________________________________________________________________________
| From: | "Ian Scott" <jabiru22(at)yahoo.com.au> |
| Subject: | Cheap blind encoder. |
HI again,
Is there any difference between
ACK A-30 ALTITUDE ENCODER P/N A-30 $178.000 USD (seems to come with
harness and static fittings Aircraft spruce and
Ameri-King AK-350 30,000 ft. 11-12010 $152.000 USD Aircraft spruce
I am about to order one of them, to talk to the microair 2000
transponder.
Thanks
Ian
________________________________________________________________________________
| From: | "Paul McAllister" <paul.mcallister(at)qia.net> |
| Subject: | Isolation amplifier |
Hi Bob,
Has this project progressed any further? Are you contemplating offering it up
as a kit?
Thanks, Paul
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Cheap blind encoder. |
>
>HI again,
>
>Is there any difference between
>
>ACK A-30 ALTITUDE ENCODER P/N A-30 $178.000 USD (seems to come with
>harness and static fittings Aircraft spruce and
>
>Ameri-King AK-350 30,000 ft. 11-12010 $152.000 USD Aircraft spruce
>
>I am about to order one of them, to talk to the microair 2000
>transponder.
Either one is fine . . .
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 with aux battery -- a few questions |
>
>
>Bob:
>
>I posted this question last weekend while you were out of town (sorry, I
>didn't know you were gone). Perhaps it got lost somewhere in your inbox
>somewhere, so I'm reposting it now with some slight changes. I'd really like
>your comments.
Sorry for the delay . . . holding a few extra dragons
a bay . . .
>I'm planning a Z-13 architecture with an additional small (4.5 AH) battery
>to support one side of a dual electronic ignition in the very unlikely event
>that the main battery goes inop for whatever reason. I perfer this to two
>full-sized batteries because it offers unlimited endurance and it weighs
>less.
fine . . .
>I'm making an assumption here, and that is that a 4.5 AH battery can support
>the operation of either the SD-8 or a standard alternator like the L-40. If
>this is *not* the case (e.g. I should only use a larger battery with the
>larger alternator), then the below-proposed system is overly complicated and
>I can slim it down somewhat. I just figured that if I am going to install a
>second small battery just incase the main battery goes inop, it might as well
>be able to make either of my alternators run as well.
Why have the little battery support anything BUT the second ignition?
>Anyway, I propose connecting the 4.5 AH battery directly to the #2 ignition
>with a fuesable link.
Okay . . .
> I will also connect it to the always-hot side of the
>main battery contactor through a S704-1 relay. I will call the switch for the
>relay the "Aux Battery Bus Tie," and it will be open for starting and closed
>for all other operations EXCEPT for when both alternators are inop.
. . . correct
> In that
>case, I'd open the relay to split the batteries so I have more control over
>battery endurance.
With dual alternator failure, I'd open the battery tie relay
-AND- shut down the alternator on the Aux battery. It's the last
ditch reserve which you're never going to need . . . and we
know the engine runs fine on one electronic ignition . . . hundreds
of airplanes do it every day when they run electronic paired
with a magneto . . . the magneto contributes nothing at manifold
pressures below 25" or so.
>Additionally, the power to the coil in the relay will come from BOTH
>batteries, via diodes. This will allow the relay to be powered from either
>battery without allowing current to flow from one battery to the other unless
>the relay is actually closed.
That's okay . . .
> I think this would be useful in the unlikely
>event of a battery-inop situation (which is the only reason I'm installing a
>second small battery in the first place). If the aux battery goes inop, I can
>still use juice from the main battery to hold the relay closed and thereby
>power the #2 ign from the main battery.
. . . whoa . . you're piling so many multiple failures on
top of each other that folks may be wondering if you're
getting paranoid . . . or identifying with too many
dark-n-stormy-night stories. This IS B&C equipment you're
considering . . . no? Failure rates on that stuff for
other than user induced damage has been very close
to zero for over ten years.
Had a builder loose a 200G a few weeks ago. Turned out
to be improperly installed terminals that worked anyway
for a very long time.
>Alternatively, if the main battery
>goes inop, I can use juice from the aux battery to hold the relay closed and
>thereby allow the aux battery to be available to support either the L-40 or
>the SD-8 alternator.
If it were my airplane, I'd take Z-13 as is and add the second
battery + S704 to support the second ignition. I'd probably even
use an LVWarn/Aux Battery Management Module to run the S704
relay . . . but manual is fine too as long as you DO have
active notification of low voltage by other means.
>With this architecture, the only time I'd be without electrical power on the
>e-bus and powering only the #2 ign directly from the aux battery is if the
>main battery and both alternators died -- highly unlikely.
You're more unlikely to have problems do to wiring complexity
and/or system management errors than for multiple failures
cited. Obviously, you can wire it any way you wish but if it
were my airplane, a simple addition of battery, two diodes
as you've proposed, and a battery switch would take care
of the second ignition just fine . . . also, a new 4.5 a.h.
battery goes into that slot every year. You can run the main
battery longer since you have two engine driven power sources
that offer unlimited endurance without draining either
battery.
>Questions:
>
>Once again, I'm making the assumption that a small battery will support
>either the SD-8 or the L-40 alternator. Is this correct?
yeah . . . but I wouldn't do it.
>If the small aux battery somehow got discharged, what prevents it from
>accepting too much current from the main alternator through its relatively
>small wiring connections (12 AWG)? Is there something I'm missing, inherent
>in the way batteries accept a charging current, that would prevent this wire
>from being overloaded?
RG batteries are pretty tolerant of an occasional rapid
energy stuffing . . . it'll be okay . . . especially
if you replace it every annual.
>What type of diodes should I use with the relay? The same 1N5400s that you
>show on Z-14?
They're fine or 1N400x series too. You're going to have
three diodes come together into one terminal on coil(+)
so the 1N400x are probably the best choice (smaller wires)
You can take diode(-) ends to the other three relay
connections to share terminals with lead wires. 12AWG
is whopping too big . . . 22 or 20 AWG is fine for
a small battery like that.
Bob . . .
________________________________________________________________________________
| Subject: | Cheap blind encoder. |
The ACK has a very short plastic barb-type fitting to connect the static
source. I found it a PITA to get a hose clamped to it. The Ameri-king has a
threaded port to use a variety of fittings. I had the ACK on the RV and have
the Ameri-king on my Navion. They are functionally equivalent but I'd buy
the Ameri-king if I needed another. FWIW the pin-outs are identical.
Regards,
Greg Young - Houston (DWH)
RV-6 N6GY - project Phoenix
Navion N5221K - just an XXL RV-6A
>
>
> HI again,
>
> Is there any difference between
>
> ACK A-30 ALTITUDE ENCODER P/N A-30 $178.000 USD (seems to come with
> harness and static fittings Aircraft spruce and
>
> Ameri-King AK-350 30,000 ft. 11-12010 $152.000 USD Aircraft spruce
>
> I am about to order one of them, to talk to the microair 2000
> transponder.
>
>
> Thanks
>
> Ian
>
________________________________________________________________________________
| From: | Geoff Evans <hellothaimassage(at)yahoo.com> |
| Subject: | Re: Z-13 with aux battery -- a few questions |
Bob,
>>>
Sorry for the delay . . . holding a few extra dragons a bay . . .
<<<
No problem at all..
>>>
Why have the little battery support anything BUT the second ignition?
<<<
It won't, with the exception of being able to stabilize the SD-8 in the
unlikely event the main battery goes tango uniform. After all, the only
reason I'm installing the second battery in the first place is for that same
unlikely event, so I figure I ought to be able to put that small battery on
the bus with the SD-8 and still have unlimited endurance.
>>>
. . . whoa . . you're piling so many multiple failures on
top of each other that folks may be wondering if you're
getting paranoid
<<<
Not paranoid.. I just figure that if I'm going to carry around an aux
battery, that I ought to be able to power its relay from either itself or the
main battery. For the cost of a 2-cent diode, I'll be able to deal with an
additional electrical malfunction that probably won't ever happen anyway. It
just somehow seems wrong to me to put a battery in an airplane and then
restrict the way it can be used.
>>>
If it were my airplane, I'd take Z-13 as is and add the second
battery + S704 to support the second ignition. I'd probably even
use an LVWarn/Aux Battery Management Module to run the S704
relay . . . but manual is fine too as long as you DO have
active notification of low voltage by other means.
<<<
The only problem I see with the ABMM driving that relay (by sensing e-bus
voltage) is that if the main battery does go tango uniform, the ABMM will
open the relay and therefore subsequently render the SD-8 useless (because it
won't have a battery to stabilize it). I'd also lose the entire e-bus in this
situation. Of course, with the OFF-AUTO-ON switch, I could force the aux
battery back on the bus, using it to bring up the SD-8 and thereby repowering
the e-bus.
Anyway, is the low voltage warning light from the main alternator controller
good enough, or are you suggesting that I also need a low voltage monitor on
the line going to the aux battery? I figure that if I do have a main
alternator failure and have to start up the SD-8, I'm going to be paying *a
lot* more attention to the voltmeter that will be on the e-bus.
>>>
>Once again, I'm making the assumption that a small battery will support
>either the SD-8 or the L-40 alternator. Is this correct?
yeah . . . but I wouldn't do it.
<<<
Curious.. Why not?
>>>
RG batteries are pretty tolerant of an occasional rapid
energy stuffing . . . it'll be okay . . . especially
if you replace it every annual.
<<<
I wasn't worried so much about the battery, but about the wire going to it.
If I use 18-20 AWG wire going to the aux battery, what prevents the main
alternator from pumping 20 amps down this wire if the aux battery is deeply
discharged?
>>>
They're fine or 1N400x series too. You're going to have
three diodes come together into one terminal on coil(+)
so the 1N400x are probably the best choice (smaller wires)
You can take diode(-) ends to the other three relay
connections to share terminals with lead wires.
<<<
Three diodes? Does the S704-1 need a spike catcher as well (like the
contactors do)?
Once again, thanks so much for your time!
If it helps, I've added the setup I described to the Z-13 drawing and made a
few other modifications. You can download it at:
http://home.attbi.com/~rv8/My_System.dwg
-Geoff
RV-8
__________________________________
http://search.yahoo.com
________________________________________________________________________________
| From: | "Dan Checkoway" <dan(at)rvproject.com> |
| Subject: | VERY confused about AMP Mate-N-Lok connectors |
I'm sitting here looking at the Digikey & Mouser catalogs, and I'm totally
confused about AMP Mate-N-Lok connectors. There are Commercial, Universal,
and Universal II. Each one seems to use a mutually exclusive pin/socket
type.
Then...ok, let's say I've got 22 AWG wire that needs to be connected. I'm
looking at the contacts selection and there are "30-22AWG" and "24-18AWG"
ranges. Then there are brass, brass gold, brass pre-tin, phosphor bronze,
etc.
Then there's what Terminal Town sells, and who knows what that stuff is.
I've looked on a zillion aircraft builder web sites and sure, everybody says
to use Mate-N-Lok connectors. Ok, would if I could...nobody spells out the
specific parts!
SHEEEEESH.
Can somebody give me a CLEAR answer about which connectors are ideal for
free-hanging applications in aircraft?
How about the required tools? Since these catalogs seem to sell different
crimpers for different style connector contacts (yes, the crimper part #s
are *different*), I can't tell what's what.
Is the BCT-1 a crimp-all-end-all tool?
Frustrated and confused,
)_( Dan
RV-7 N714D
http://www.rvproject.com
________________________________________________________________________________
| From: | "Dan Checkoway" <dan(at)rvproject.com> |
| Subject: | Re: cutting heavy gauge wire, contactor diodes, copper |
alloys
> >2) What type of diode(s) should be used on battery/starter contactors? I
> >couldn't find any spec on it in the AEC book. I have a 3-terminal
battery
> >contactor (ES 24115 from Van's) and a 4-terminal starter contactor (ES
> >24021). I've checked the archives and found varying info...1N5xxx or
1N4xxx
> >or other?
>
> The diode needs to be rated for 15v or more and be capable
> of carrying the same current that it takes to energize the
> contactor (1 to 5A) for a few milliseconds. About any
> diode rectifier is electrically suited to the task. 1N400x
> series are fine but they are rather small, sometimes glass
> devices that are fragile compared to the 1N540x series
> devices that are always 1/4" diam plastic and 20AWG leads.
>
> If you look at the diodes we supply on the S700 series
> contactors at
>
> http://www.aeroelectric.com/Catalog/switch/s701-1l.jpg
> and http://www.aeroelectric.com/Catalog/switch/s701-2.jpg
>
> . . . you can see how the mechanically more robust
> 3A diodes lend themselves to the task.
>
> ANY diode you can find will work electrically . . .
> chose for convenience of application.
Sorry to bring this back up, but the vagueness of "ANY diode" has left my
head spinning as I look at page 468 of the Digikey catalog (Sept-Dec 2002).
There's a selection of 1N540x diodes (bridge rectifiers?), the variation
being the "max peak reverse voltage." It ranges from 50V to 1000V. Can I
assume that 50V is sufficient? Is this voltage what you meant by "rated for
15v"? They all cost the same (32 cents), but does "going big" equate to
being conservative?
Or should I really just throw a dart at the page and choose one that way?
8-)
I have no clue what any of this means (I am no electrical engineer!), so any
light you can shed is much appreciated.
Thanks in advance,
)_( Dan
RV-7 N714D
http://www.rvproject.com
________________________________________________________________________________
| From: | Charlie & Tupper England <cengland(at)netdoor.com> |
| Subject: | Re: cutting heavy gauge wire, contactor diodes, |
copper alloys
Dan Checkoway wrote:
>
>
>
>>>2) What type of diode(s) should be used on battery/starter contactors? I
>>>couldn't find any spec on it in the AEC book. I have a 3-terminal
>>>
>>>
>battery
>
>
>>>contactor (ES 24115 from Van's) and a 4-terminal starter contactor (ES
>>>24021). I've checked the archives and found varying info...1N5xxx or
>>>
>>>
>1N4xxx
>
>
>>>or other?
>>>
>>>
>> The diode needs to be rated for 15v or more and be capable
>> of carrying the same current that it takes to energize the
>> contactor (1 to 5A) for a few milliseconds. About any
>> diode rectifier is electrically suited to the task. 1N400x
>> series are fine but they are rather small, sometimes glass
>> devices that are fragile compared to the 1N540x series
>> devices that are always 1/4" diam plastic and 20AWG leads.
>>
>> If you look at the diodes we supply on the S700 series
>> contactors at
>>
>> http://www.aeroelectric.com/Catalog/switch/s701-1l.jpg
>> and http://www.aeroelectric.com/Catalog/switch/s701-2.jpg
>>
>> . . . you can see how the mechanically more robust
>> 3A diodes lend themselves to the task.
>>
>> ANY diode you can find will work electrically . . .
>> chose for convenience of application.
>>
>>
>
>Sorry to bring this back up, but the vagueness of "ANY diode" has left my
>head spinning as I look at page 468 of the Digikey catalog (Sept-Dec 2002).
>There's a selection of 1N540x diodes (bridge rectifiers?), the variation
>being the "max peak reverse voltage." It ranges from 50V to 1000V. Can I
>assume that 50V is sufficient? Is this voltage what you meant by "rated for
>15v"? They all cost the same (32 cents), but does "going big" equate to
>being conservative?
>
>Or should I really just throw a dart at the page and choose one that way?
>8-)
>
>I have no clue what any of this means (I am no electrical engineer!), so any
>light you can shed is much appreciated.
>
>Thanks in advance,
>)_( Dan
>RV-7 N714D
>http://www.rvproject.com
>
Think in terms of a one-way check valve in a water line. The higher the
voltage rating, the more reverse pressure (voltage) the diode can take
before failing to block current flow, just like a check valve has
limited strength as to how much water pressure it can take before
allowing water to flow backward in the pipe. Higher voltage rating won't
hurt anything unless it causes the device's physical size to increase to
the point that it becomes hard to use in the intended application. In
this application, 'going big' can equate to being (unnecessarily ?)
conservative, but it won't hurt either.
Charlie
________________________________________________________________________________
| From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
I would of course defer to Bob Nuckolls on this, BUT I've always
accepted that a diode needs about three times the Reverse Voltage Rating
that it protects. That's in radio work where one seldom encounters excessive
voltage leaps as in aircraft. So, unless corrected, I'll be assuming the 3X
rule when choosing diodes.
Ferg
Europa A064
________________________________________________________________________________
| From: | "James Foerster" <jmfpublic(at)attbi.com> |
| Subject: | Stick It-Your-Ear Headsets |
These were reviewed in the Feb.2003 Aviation Consumer. To summarize: the Panther
unit requires molded earpieces, and one earpiece is the mic. It is monaural.
If you ear, there is a mute button. It needs ear lube to get it in. You
mold the earpiece yourself. Lionel Lavenue, the reviewer, didn't like ear lube,
but his wife thought it was better than any headset that she had used. Noise
reduction was good.
They also tested the Auricomm and the UltraFlite from Quiet Technologies. These
both are stereo with a mic boom, and form the seal with malleable-foam earplugs
with the sound channel in the middle. The UltraFlite has a headband, the
Auricomm does not. Both author and his wife like these the best, and the noise
reduction was as good as the Panther. They come with various size foam ear
cushions which are replacable. Obviously, these can be shared, the Panther cannot.
Panther can also be bought with a "universal" earpiece, but that was not
tested. After reading the review, the Panther might be best with the universal
earpiece. What do you think, Ken Melvin? Panther is $495, the others are
$325.
www.pantherelectronics.com and www.quiettechnologies.com
Jim Foerster Jabiru J400 50% done 75% to go
________________________________________________________________________________
| From: | irampil(at)notes.cc.sunysb.edu |
| Subject: | Re: Isolation Amp/Mixer Board |
05/26/2003 07:13:42 PM
Me too Bob, when you are happy with it!
Ira
________________________________________________________________________________
| From: | Randyhux(at)aol.com |
| Subject: | Aluminum Cleaner |
This company makes a great detergent, I have used some of it in medical
applications but have not tried their aluminum cleaner.
Click here: Alconox, Inc. - Home: The leader in critical cleaning detergents
________________________________________________________________________________
| From: | Melvinke(at)aol.com |
| Subject: | Re: Stick It-Your-Ear Headsets |
I can only surmise that the molded earpiece has a lot to do with the
effectiveness of the passive noise reduction that is achieved with the Panther
unit. I
flew today with both the Bose and the Panther, and confirmed that the noise
reduction appears as good in each. The Panther is more comfortable in that
there is no heavy headband across one's scalp, there is no problem with wearing
glasses (which interfere with the effective sealing of the Bose ear muffs, which
wear quickly and leak silicone gel if worn with glasses), and G-maneuvers
don't dislodge the Panther as they do the Bose. Further, the Panther allows for
the wearing of a hat, which is necessary under a bubble canopy on a long trip.
Voice transmission is excellent with the Panther, albeit with a slightly
different timbre to that achieved with a standard microphone. Clean external
auditory canals are a must, of course! Pressure equalization with altitude occurs
easily and comfortably, despite the molded fit of the ear pieces.
Kenneth Melvin; RV4.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: VERY confused about AMP Mate-N-Lok |
connectors
>
>I'm sitting here looking at the Digikey & Mouser catalogs, and I'm totally
>confused about AMP Mate-N-Lok connectors. There are Commercial, Universal,
>and Universal II. Each one seems to use a mutually exclusive pin/socket
>type.
>
>Then...ok, let's say I've got 22 AWG wire that needs to be connected. I'm
May 13, 2003 - May 26, 2003
AeroElectric-Archive.digest.vol-ca