Today's Message Index:
----------------------
1. 05:54 AM - Re: Re: ROCHESTER FUEL LEVEL INDICATOR WIRING (Bob McCallum)
2. 06:26 AM - Re: Battery Maintainer (Geoff Heap)
3. 07:01 AM - Re: Re: Battery Maintainer (Robert L. Nuckolls, III)
4. 07:55 AM - Re: Check this out (Robert L. Nuckolls, III)
5. 07:56 AM - Re: Re: ROCHESTER FUEL LEVEL INDICATOR WIRING (Robert L. Nuckolls, III)
6. 08:30 AM - Re: Battery Maintainer (Geoff Heap)
7. 08:52 AM - Radio noises (Jeff Page)
8. 09:31 AM - Re: Silver plating (Ernest Christley)
9. 09:53 AM - Re: Check this out (Terry Watson)
10. 12:10 PM - Re: Check this out (Robert L. Nuckolls, III)
11. 12:50 PM - Re: Radio noises (Robert L. Nuckolls, III)
12. 01:15 PM - Re: Check this out (Chuck Jensen)
13. 02:17 PM - Re: Check this out (Robert L. Nuckolls, III)
14. 03:04 PM - Re: ROCHESTER FUEL LEVEL INDICATOR WIRING (Thruster87)
15. 07:11 PM - Re: Magneto Wiring with 2-50 switches and toggle switch starting (messydeer)
16. 09:12 PM - Pitot tube heater requirements . . . (Robert L. Nuckolls, III)
Message 1
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| Subject: | Re: ROCHESTER FUEL LEVEL INDICATOR WIRING |
Alan;
I have no direct knowledge of these particular gauges, but in the automotive
world any terminal marked "sen" would be the sensor terminal and would be
the terminal which would be connected to your tank sending unit which would
then ground this terminal through whatever resistance resulted from the
current fuel level. i.e. this is where you would connect your "resistor to
ground" (your 45 ohm test resistor for example)
The connections you said you used for "test" support this as you've done the
same thing only backwards. (You've applied 12 Volts to ground and grounded
the power lead through your resistance. Should still read approx 1/2 scale
as your results show.)
The "ign" terminal is connected to the ignition live connection or in the
aviation world would be supplied with battery power.
The third terminal, the centre one as you call it, is ground, an hypothesis
which is supported by your information that it also seems to be supplying
the ground connection for the light.
As I said this is logic based on the automotive industry with no direct
knowledge of the specific parts you have.
Good luck
Bob McC
> -----Original Message-----
> From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-
> server@matronics.com] On Behalf Of Thruster87
> Sent: Friday, August 07, 2009 2:11 AM
> To: aeroelectric-list@matronics.com
> Subject: AeroElectric-List: Re: ROCHESTER FUEL LEVEL INDICATOR WIRING
>
<alania@optusnet.com.au>
>
> Still trying to get these fuel gauges to work. The sender units are 10-76
ohms and the
> ROCHESTER FUEL LEVEL Indicators are 0 - 90 ohms also if I apply 12v to
the sen
> terminal and put a 45 ohm resister inline to ground on the center terminal
[the center
> terminal has a metal plate which extends to around the light bulb hole ]
it reads 1/2
> way on the gauge which appears to be the correct value.Still not sure
what the ign
> terminal is used for then !!!! Cheers Alan
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=256462#256462
>
>
>
>
>
>
>
> _-
> =====================================================
> =====
> _-
> =====================================================
> =====
> _-
> =====================================================
> =====
> _-
> =====================================================
> =====
>
>
Message 2
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| Subject: | Re: Battery Maintainer |
Guys.
Ref Schumacher SEM1562A 1.5-Amp Automatic Battery Charger
The advertising on this products packaging states "FOR 6 AND 12 VOLT LEAD ACID
BATTERIES" Please confirm, this is good (safe) for Gel batteries??.....Geoff
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=256487#256487
Message 3
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| Subject: | Re: Battery Maintainer |
At 08:24 AM 8/7/2009, you wrote:
>
>Guys.
>Ref Schumacher SEM1562A 1.5-Amp Automatic Battery Charger
>The advertising on this products packaging states "FOR 6 AND 12 VOLT
>LEAD ACID BATTERIES" Please confirm, this is good (safe) for Gel
>batteries??.....Geoff
"Gel" batteries are flooded batteries with some
jello added to the electrolyte to make it less
likely to leak. They're still a lead-acid device
that operates on the same chemistry as their
flooded ancestors and recombinant gas descendants.
The 1562 battery charger/maintainer offers
satisfactory performance for servicing your
batteries. You asked about a "gel" battery.
There are a lot folks that erroneously call
a sealed, vented, lead-acid, recombinant-gas
battery a "gel cell". I'm guessing that the
battery you're referring to is not a gel cell.
Gel batteries are still made and they're
preferred for deep cycle, spill-resistant
applications like wheel chairs. But they
make up a very small percentage of the
lead-acid battery market.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Message 4
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| Subject: | Re: Check this out |
At 12:42 AM 8/7/2009, you wrote:
>
>The news may not be as bad as it seems to some.
>
>http://www.instructables.com/
>
>I am subscribed to their email publication and have seen many new
>ideas and new uses for old stuff.
>
>I think one problem is that our society doesn't value a jack of all
>trades. Specialization is where the money is.
Unfortunately, public education does little if
anything to suggest the alternative. One of my
most revered philosophers was Robert Heinlein
who wrote . . .
"A human being should be able to change a diaper, plan an
invasion, butcher a hog, conn a ship, design a building,
write a sonnet, balance accounts, build a wall, set a bone,
comfort the dying, take orders, give orders, cooperate, act
alone, solve equations, analyze a new problem, pitch manure,
program a computer, cook a tasty meal, fight efficiently,
die gallantly. Specialization is for insects."
While the list of tasks we're willing and able to
do (or learn) may vary, the ideas behind his
sentiments are quite clear. Now, how to share
this recipe for success with our children?
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Message 5
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| Subject: | Re: ROCHESTER FUEL LEVEL INDICATOR WIRING |
At 01:10 AM 8/7/2009, you wrote:
>
>Still trying to get these fuel gauges to work. The sender units are
>10-76 ohms and the ROCHESTER FUEL LEVEL Indicators are 0 - 90 ohms
>also if I apply 12v to the sen terminal and put a 45 ohm resister
>inline to ground on the center terminal [the center terminal has a
>metal plate which extends to around the light bulb hole ] it reads
>1/2 way on the gauge which appears to be the correct value.Still
>not sure what the ign terminal is used for then !!!! Cheers Alan
Did you try hooking 12v to IGN, center to ground
and SEN to ground through a 45 ohm resistor? The
meanings of the markings are quite clear. Applying
12v to a SEN terminal will yield meaningless results
and may damage the instrument.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Message 6
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| Subject: | Re: Battery Maintainer |
Bob
"There are a lot folks that erroneously call
a sealed, vented, lead-acid, recombinant-gas
battery a "gel cell". I'm guessing that the
battery you're referring to is not a gel cell."
Dead right. Thats what I've got....Geoff
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=256510#256510
Message 7
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Advice please.
A friend of mine has a Pitts he recently purchased and has been
fighting to fix ugly noises in the radio since he bought it.
The electrical system is quite simple - no lights, VFR panel, single
radio, transponder, basic intercom, battery, alternator and starter.
The radio is a King KX145, which has reportedly passed a bench test.
The noise sounds to me like engine induced noise. It is not clean
white noise, but continuous static with lots of scratches and pops in
it.
Before I got involved, the radio was bench tested. The original
antenna on the turtledeck was taken off the and grounds cleaned up.
The avionics shop talked him into a new antenna, which was installed
on the bottom of the aircraft instead, and a new cable which connects
to about a 1 foot long pigtail coming out of the back of the radio
rack. Now he has spent over $1000 and the problem persists.
So yesterday, I got in the plane with him and we played around on the
ground. The static exists whenever the radio's squelch is
unsquelched, or when receiving a less than very strong signal. That
is, the tower and ATIS are cleanly heard, but an aircraft calling from
12 miles is easily understood among a background of static. This is
with the engine not running and just the radio powered on.
With the engine running the static is pretty much the same, except you
need to turn the volume up a bit due to the external engine and wind
noise. The static does not change when the alternator is switched on
and off. It does not change at all with engine rpm or when switching
mags on and off. So even though it sounds very much like engine
interference, it must not be, since it can be heard with the engine
stopped.
Curiously, the static is much louder as the plane is oriented toward
the south-east. So listening to the ATIS broadcast, the audio is
clean for about 270 degrees of the circle, but the voice stays the
same, but the background static dramatically increases to almost as
loud as the voice, when facing the southeast quadrant. This
directional characteristic is the same whether behind the hangars, or
out on the main ramp a half mile away.
To be sure the VOR antenna and the COM antenna cables were not mixed
up, I unplugged them one at a time and got no difference. In the end,
we had all the antenna cables unplugged and the receive audio was the
same ???? Both handhelds available receive no audible signal without
their antenna connected. So how can we be picking up the ATIS without
an antenna ? Could the signal be picked up via the intercom wires ?
The intercom requires pushing a switch to talk to the other person.
Yesterday, I pulled the jacks off the panels. They are wired with
proper shielded cable and I installed insulated washers at the jacks,
just in case there was some grounding problem. No change.
Generally tranmit is quite good. I have picked up this aircraft, very
clearly, when flying my own 20 miles apart. Generally the tower
reports our transmissions as 5x5, however, when on the ramp facing
southeast, they report the transmission is slightly garbled. The
owner reports sometimes having to change direction in flight in order
to call up the tower.
Ideas what should be done next ? I have suggested another bench test
of the radio, which probably won't tell us anything that wasn't
revealed the first time. I don't have access to a VSWR meter. The
wiring is pretty shabby, so perhaps just re-wiring it all from scratch
is a good idea.
I intend to make a patch cable that will allow testing the entire
cable and antenna installation with a handheld radio.
Jeff Page
Dream Aircraft Tundra #10
Message 8
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| Subject: | Re: Silver plating |
rparigor@SUFFOLK.LIB.NY.US wrote:
> Hi ernest
>
> What's your thoughts on silver plating magic powder I sent you?
>
> I did a test putting samples outside, copper very tarnished, silver
> holding up well. On plane my thin wide crossfeed made out of copper is
> very tarnished and silver looks still fine.
>
The experiment has made as much progress as the rest of my project since
I got laid off. None. I think I might have logged as many as 10 hours
of building time since February.
OTOH, I do have some really cool software to sell if you're involved
with amateur wrestling.
--
Ernest Christley, President
Ernest@TechnicalTakedown.com
TechnicalTakedown, LLC
www.TechnicalTakedown.com
101 Steep Bank Dr.
Cary, NC 27518
(919) 741-9397
Message 9
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My suggestion about a very large contributing factor to this problem is that
so few of us are raised on a farm or ranch anymore. Any farm kid learns that
if something needs doing, you need to be able to do it; when something
breaks, you need to be able to fix it. To eat, you need to plant seeds and
assure their growth, or to be willing to slaughter an animal you have known
all its life. I don't know how you translate this into an urban lifestyle
where we may be many layers away from the source of what we want or need,
but it's a great loss if we can't do it. Maybe it's just teaching kids the
joy of working with their head AND their hands at the same time, or the
satisfaction of playing with or living in or riding in or flying in
something they built with their own hands.
Terry
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Friday, August 07, 2009 7:54 AM
Subject: Re: AeroElectric-List: Check this out
<nuckolls.bob@aeroelectric.com>
At 12:42 AM 8/7/2009, you wrote:
>
>The news may not be as bad as it seems to some.
>
>http://www.instructables.com/
>
>I am subscribed to their email publication and have seen many new
>ideas and new uses for old stuff.
>
>I think one problem is that our society doesn't value a jack of all
>trades. Specialization is where the money is.
Unfortunately, public education does little if
anything to suggest the alternative. One of my
most revered philosophers was Robert Heinlein
who wrote . . .
"A human being should be able to change a diaper, plan an
invasion, butcher a hog, conn a ship, design a building,
write a sonnet, balance accounts, build a wall, set a bone,
comfort the dying, take orders, give orders, cooperate, act
alone, solve equations, analyze a new problem, pitch manure,
program a computer, cook a tasty meal, fight efficiently,
die gallantly. Specialization is for insects."
While the list of tasks we're willing and able to
do (or learn) may vary, the ideas behind his
sentiments are quite clear. Now, how to share
this recipe for success with our children?
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Message 10
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At 11:45 AM 8/7/2009, you wrote:
>
>My suggestion about a very large contributing factor to this problem is that
>so few of us are raised on a farm or ranch anymore. Any farm kid learns that
>if something needs doing, you need to be able to do it; when something
>breaks, you need to be able to fix it.
You are quite correct sir. I've lived both sides of that
coin. My grandfather came to Wichita from Arkansas as a
nurseryman but skilled in building every resource needed to support
that trade. By the time he was 40 he had built, operated and
sold a nursery, started a contracting services activity.
Traded land in Wichita for farm land in Medicine Lodge and
added farming to his constellation of endeavors.
This is one reason I'm moving back to M.L. and hoping to
take all my kids and grandchildren with me. We have great-
grandpa's and grandpa's legacies along with a home that
will house woodworking, hvac, locksmithing, electronics,
catering, tree trimming and publishing services managed
by two professional teachers and four professional craftsmen.
It's my new career goal to die stone broke with
my family living in paid-for houses and radiating a
culture of "how can we help you today?" mentality.
>Maybe it's just teaching kids the
>joy of working with their head AND their hands at the same time, or the
>satisfaction of playing with or living in or riding in or flying in
>something they built with their own hands.
Yup, that's what launched my father's lifestyle and
ultimately my own . . .
http://aeroelectric.com/articles/In_Memory_of_Robert_L_Nuckolls_Jr.pdf
Unfortunately, difficult to achieve in an Wii, Ipod,
let's-get-eternally high/excited/pleasured-culture. I'm seeing only
vestiges of that in M.L. so far. Perhaps we can help
plant the seeds of a few old but well proven recipes
for success there. I'll be seeking out other real teachers
first.
Bob . . .
Message 11
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| Subject: | Re: Radio noises |
>\\
At 10:51 AM 8/7/2009, you wrote:
Advice please.
<snip>
Now he has spent over $1000 and the problem persists.
So yesterday, I got in the plane with him and we played around on the
ground. The static exists whenever the radio's squelch is
unsquelched, or when receiving a less than very strong signal. That
is, the tower and ATIS are cleanly heard, but an aircraft calling from
12 miles is easily understood among a background of static. This is
with the engine not running and just the radio powered on.
What, if any other accessories are operating on the
airplane during this test. Try pulling all other breakers/
fuses except radio/audio system to search out possible
cause/effect on board the aircraft. In particular, make
sure the alternator's regulator is not powered up.
With the engine running the static is pretty much the same, except you
need to turn the volume up a bit due to the external engine and wind
noise. The static does not change when the alternator is switched on
and off.
Oops, Okay . . . scratch the alternator.
It does not change at all with engine rpm or when switching
mags on and off. So even though it sounds very much like engine
interference, it must not be, since it can be heard with the engine
stopped.
agreed.
Curiously, the static is much louder as the plane is oriented toward
the south-east. So listening to the ATIS broadcast, the audio is
clean for about 270 degrees of the circle, but the voice stays the
same, but the background static dramatically increases to almost as
loud as the voice, when facing the southeast quadrant. This
directional characteristic is the same whether behind the hangars, or
out on the main ramp a half mile away.
Does the noise go away when you disconnect the antenna?
Have you checked for presence of this noise while away
from the field? The directional effects suggest possible
local source on the ground.
To be sure the VOR antenna and the COM antenna cables were not mixed
up, I unplugged them one at a time and got no difference. In the end,
we had all the antenna cables unplugged and the receive audio was the
same ????
Okay, that answers that question.
Both handhelds available receive no audible signal without
their antenna connected. So how can we be picking up the ATIS without
an antenna ? Could the signal be picked up via the intercom wires ?
Good question. Back in the good ol' days the radios for light
aircraft were not subjected to many sources of outside stimulus
and testing for vulnerabilities on other than power and antenna
lines was limited. Nowadays, we look at ALL wires which enter
or exit the box along with shielding integrity of the box itself.
This is one of Ed King's earliest crystal synthesized radios
that came out about 1975 as I recall. Have you checked to see
if this radio still qualifies under tightened frequency
accuracy and receiver bandwidth requirements were levied for
8.33 Khz channel spacing?
The intercom requires pushing a switch to talk to the other person.
Yesterday, I pulled the jacks off the panels. They are wired with
proper shielded cable and I installed insulated washers at the jacks,
just in case there was some grounding problem. No change.
Generally tranmit is quite good. I have picked up this aircraft, very
clearly, when flying my own 20 miles apart. Generally the tower
reports our transmissions as 5x5, however, when on the ramp facing
southeast, they report the transmission is slightly garbled. The
owner reports sometimes having to change direction in flight in order
to call up the tower.
Hmmmm happens in flight too and is getting into the
the transmitter?
Ideas what should be done next ? I have suggested another bench test
of the radio, which probably won't tell us anything that wasn't
revealed the first time. I don't have access to a VSWR meter. The
wiring is pretty shabby, so perhaps just re-wiring it all from scratch
is a good idea.
I intend to make a patch cable that will allow testing the entire
cable and antenna installation with a handheld radio.
Good lick too. I was considering that suggestion. Also, check
performance at the top end of the comm frequency rage with a
remotely located hand held for weak signal. See if the problem
is frequency sensitive.
Bob . . .
Message 12
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Bob,
That is a long list of goals, but I believe I have been successful in achieving
at least one already....the 'stone broke' thing. lol
Chuck
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert
L. Nuckolls, III
Sent: Friday, August 07, 2009 3:09 PM
Subject: RE: AeroElectric-List: Check this out
This is one reason I'm moving back to M.L. and hoping to
take all my kids and grandchildren with me. We have great-
grandpa's and grandpa's legacies along with a home that
will house woodworking, hvac, locksmithing, electronics,
catering, tree trimming and publishing services managed
by two professional teachers and four professional craftsmen.
It's my new career goal to die stone broke with
my family living in paid-for houses and radiating a
culture of "how can we help you today?" mentality.
Message 13
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At 02:55 PM 8/7/2009, you wrote:
>
>Bob,
>
>That is a long list of goals, but I believe I have been successful
>in achieving at least one already....the 'stone broke' thing. lol
Don't know which (if any) combination of those
skills will come to fruition as a goal. They
exist to some degree in some of us. All we can
do is offer them up to each other and to our
neighbors as opportunities to be exploited.
In the mean time, my working goal is the houses.
Two down and two to go.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
Message 14
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| Subject: | Re: ROCHESTER FUEL LEVEL INDICATOR WIRING |
Received a wiring diagrams from Aircraft Spruce So thank you all for your help
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=256565#256565
Attachments:
http://forums.matronics.com//files/3090_106instructions2_194.pdf
http://forums.matronics.com//files/3090_106instructions1_282.pdf
Message 15
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| Subject: | Re: Magneto Wiring with 2-50 switches and toggle switch |
starting
> I also considered using the 2-50 switches but decided to use a separate push
> button to start because I like to have the ability to crank the engine
> without the mags on; sometimes useful for troubleshooting and maintenance.
>
Good point, Jay :-) Others have also mentioned that, so I think I'll go with a
push start that is separate from the mag switches. So that means I don't have
to worry about how the wiring goes for the mag/starter switch combo anymore.
Yippie!
And I think I understand how the mag wiring works now. I have dual mag ignitions
in my Jab 3300. I was also told that they don't have impulse coupling either,
which makes me wonder if one or both have the 'shower of sparks' type of starting
mechanism. I've only glanced at that so far.
So I've put my thoughts on cyberpaper and with any luck there'll be a pdf file
attached below. I do have one big question that came up while I was copying the
mag drawings from Z-20. The right mag is shown wired to the switch differently
than the left. I don't know why it is shown like that.
Take care,
Dan
PS: I goofed and uploaded 2 copies of the file. They're both the same.
--------
Dan
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=256594#256594
Attachments:
http://forums.matronics.com//files/my_magneto_wiring_with_1_3_switches_145.pdf
http://forums.matronics.com//files/my_magneto_wiring_with_1_3_switches_100.pdf
Message 16
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| Subject: | Pitot tube heater requirements . . . |
>Question: I read your article on pitot tube heaters...absolutely
>right...as far as it went.
>
>What I was trying to find out was...how much power is required to
>maintain the temperature on the surface and in the ram air (Pt)
>throat above freezing in the face of a mach .82 blast at 35,000 ft
>pressure and -80 deg C???
Actually, it's really easy to keep it hot. I have
data collected from pitot tubes in flight and it's
not uncommon to see 100C surface temperatures at
max cruise, 41,000 feet altitude and in clear air.
>This will be complicated by the fact that a thermally conductive
>pitot tube is mounted to a very cold metal heat sink (aka the
>airframe). Then there is the fact that the air pressure is very
>low...basicly a cold near vacuum!!!
>
>My experience with high altitude cold is that hot things get hotter,
>and cold things get colder. The shape of the pitot head
>matters...imagine it had fins!!
The ability of air to carry away heat isn't the issue.
The ability of super-cooled WATER to carry away heat
IS the issue. This is why pitot tube temperatures in normal
conditions have little significance for operation under
icing conditions. This is why virtually every new pitot tube
installation is qualified with ICING TUNNEL tests to confirm
their ability to shed ice accumulated as a result of
super-cooled water impacts of so many grams/second/square
CM. Now, any icing tunnel worth its cost of operation
should be capable of overwhelming about any pitot tube
so that folks are aware of the tube's capabilities.
The program I worked about ten years ago was to investigate
CLEAR AIR lost of pitot data on both sides of a
biz jet at 41,000 feet. Data that returned as soon as the
airplane descended to lower, warmer altitudes. These were
pitot tubes previously qualified in a icing tunnel. The tubes
were modified based on second set of tests. However, some
airplanes (fewer) still experience the event.
So your right, the problem is messy and the answers
are not really intuitive. I'm obligated to tell you that
nobody can give you good advice on wattage, normal conditions
temperatures, etc. The physics by which heated pitot tubes
ultimately meet requirements are about 50% calculation, 40%
experience in the field and tunnel testing and 10% black art.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
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