Today's Message Index:
----------------------
1. 06:12 AM - Re: Re: RG battery mounting positions (BobsV35B@aol.com)
2. 07:19 AM - Altitude control (Gary Casey)
3. 07:23 AM - EGT PROBES (Julia)
4. 07:58 AM - Re: Altitude control (Kevin Horton)
5. 08:34 AM - Re: Altitude control (Cliff Shaw)
6. 08:34 AM - Re: Altitude control (Gerry Holland)
7. 09:01 AM - Recommendations (Tinnemaha)
8. 09:24 AM - Re: EGT PROBES (J. Oberst)
9. 10:10 AM - No Subject (Jerry2DT@aol.com)
10. 12:19 PM - Re: Altitude control (John Loram)
11. 01:22 PM - OV Protection (Tinnemaha)
12. 01:30 PM - Electronic Ignition? (Tinnemaha)
13. 02:03 PM - Re: Electronic Ignition? (J. Oberst)
14. 05:53 PM - Re: Re: Microair radio (Rino)
15. 06:07 PM - Re: Re: Microair radio (RSwanson)
16. 07:03 PM - Re: Re: Microair radio (Rino)
17. 07:27 PM - Re: Altitude control (ScramIt@aol.com)
18. 07:28 PM - Re: Electronic Ignition? (Jim Jewell)
19. 08:06 PM - Re: OV Protection (Julia)
20. 08:21 PM - Fw: Spike-catcher diode failures (KeithHallsten)
21. 08:56 PM - advanced aircraft electronics (Larry Bowen)
Message 1
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| Subject: | Re: RE: RG battery mounting positions |
--> AeroElectric-List message posted by: BobsV35B@aol.com
In a message dated 3/15/03 1:13:34 AM Central Standard Time,
jjewell@telus.net writes:
> Seek out the Concord Battery site for one. They sell Certified RG sealed
> lead acid batteries for Certified aircraft and have done so for some number
> of years now.
>
Teledyne-Gill also has RG batteries that are approved.
Happy Skies,
Old Bob
Message 2
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| Subject: | Altitude control |
--> AeroElectric-List message posted by: "Gary Casey" <glcasey@adelphia.net>
<<> I've got plans for
> a super sensitive, temperature compensated pressure
> transducer that gives me +/- 20 foot accuracy to
> 60,000 feet and better than 1% accuracy for pitot
> pressures to 300 kts.
Does this mean we will be seeing a reasonably accurate, affordable altitude
control
device in
the near future?>>
Pardon me if I don't hold my breath for this one. 20 feet of accuracy at
60,000 equates to a maximum error of .00098 psi, or 0.007% of full scale, an
accuracy not attainable by even laboratory grade sensors. At sea level 20
feet equates to 0.01 psi or 0.07% of full scale, within reach of high-end
pressure sensors, but only over a very limited temperature range. Typical
autopilots (S-TEC) use the altitude encoder with 100-foot resolution and
about 100-foot accuracy to capture an altitude, but then use a fairly
rudimentary pressure sensor to hold that altitude. A typical sensor for
that application (which we build) is about 1 to 2% accuracy over a wide
temperature range. Any modern manifold absolute pressure (MAP) sensor would
be easily capable of doing the altitude hold feature of an autopilot. I'm
using an standard Chrysler MAP sensor right now for that purpose. If one
were to use a 1% MAP sensor at a retail cost of $20 to $50 for altitude
capture the accuracy would be 274 feet at sea level and 524 feet at 20,000
feet altitude. However, the REPEATABILITY of an automotive MAP sensor over
a limited temperature range will be about 0.1% so if one were willing to do
a one-time setting of the error you could have an altitude capture error
about 1/10 of the above, or 27 feet at sea level and 52 feet at 20,000 feet.
I would think that would be about as accurate as we care about and all that
can be had today with sensors built in quantities of several million a year.
Gary Casey
Message 3
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--> AeroElectric-List message posted by: Julia <wings97302@yahoo.com>
Any pointers on mounting EGT probes - i'm having a hard time finding the courage
to drill the holes in my $1,200 4-into-1 stainless exhaust sytem?
If a probe were mounted so it stuck straight out - would that hit the cowl?? is
there plenty of clearance so any direction is ok?
thanks
---------------------------------
Message 4
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| Subject: | Re: Altitude control |
--> AeroElectric-List message posted by: Kevin Horton <khorto1537@rogers.com>
>--> AeroElectric-List message posted by: "Gary Casey" <glcasey@adelphia.net>
>
><<> I've got plans for
>> a super sensitive, temperature compensated pressure
>> transducer that gives me +/- 20 foot accuracy to
>> 60,000 feet and better than 1% accuracy for pitot
>> pressures to 300 kts.
>
>Does this mean we will be seeing a reasonably accurate, affordable altitude
>control
>device in
>the near future?>>
>
>Pardon me if I don't hold my breath for this one. 20 feet of accuracy at
>60,000 equates to a maximum error of .00098 psi, or 0.007% of full scale, an
>accuracy not attainable by even laboratory grade sensors. At sea level 20
>feet equates to 0.01 psi or 0.07% of full scale, within reach of high-end
>pressure sensors, but only over a very limited temperature range. Typical
>autopilots (S-TEC) use the altitude encoder with 100-foot resolution and
>about 100-foot accuracy to capture an altitude, but then use a fairly
>rudimentary pressure sensor to hold that altitude. A typical sensor for
>that application (which we build) is about 1 to 2% accuracy over a wide
>temperature range. Any modern manifold absolute pressure (MAP) sensor would
>be easily capable of doing the altitude hold feature of an autopilot. I'm
>using an standard Chrysler MAP sensor right now for that purpose. If one
>were to use a 1% MAP sensor at a retail cost of $20 to $50 for altitude
>capture the accuracy would be 274 feet at sea level and 524 feet at 20,000
>feet altitude. However, the REPEATABILITY of an automotive MAP sensor over
>a limited temperature range will be about 0.1% so if one were willing to do
>a one-time setting of the error you could have an altitude capture error
>about 1/10 of the above, or 27 feet at sea level and 52 feet at 20,000 feet.
>I would think that would be about as accurate as we care about and all that
>can be had today with sensors built in quantities of several million a year.
>
>Gary Casey
>
Personally, I would be willing to settle for a system where you had
to manually level the aircraft at the desired altitude, and then
engage the altitude hold mode. That way the system just has to
memorize the current pressure altitude, and react to changes. That
gets us around many of the sensor accuracy issues, as long as the
sensor accuracy doesn't drift much over an hour or so.
I'm encouraged to read that there are cheap sensors available that
would suit this simple altitude hold system. Maybe someday after I
get flying I'll look into what it would take to design such a system.
Message 5
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| Subject: | Re: Altitude control |
--> AeroElectric-List message posted by: "Cliff Shaw" <flyinggpa@attbi.com>
All
I found this web page and built the EZ Trim. It works with the Electric
trim that I already had installed.
http://hometown.aol.com/ccady/eztrim.htm
Cliff Shaw
1041 Euclid ave.
Edmonds WA 98020
(425) 776-5555
N229WC "Wile E Coyote"
> >about 1/10 of the above, or 27 feet at sea level and 52 feet at 20,000
feet.
> >I would think that would be about as accurate as we care about and all
that
> >can be had today with sensors built in quantities of several million a
year.
> >
> >Gary Casey
> >
>
> Personally, I would be willing to settle for a system where you had
> to manually level the aircraft at the desired altitude, and then
> engage the altitude hold mode. That way the system just has to
Message 6
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| Subject: | Re: Altitude control |
--> AeroElectric-List message posted by: Gerry Holland <gnholland@onetel.com>
Kevin Hi!
> I'm encouraged to read that there are cheap sensors available that
> would suit this simple altitude hold system. Maybe someday after I
> get flying I'll look into what it would take to design such a system.
>
Not sure if you were aware or not but the EZ-Trim does this task.
Website - http://members.aol.com/_ht_a/ccady/eztrim.htm
I'm building the Circuit at this time but unfortunately my Europa will
not being flying until later this year to tell you the results.
My inclination to have this function of simple Altitude hold was as a
complimentary capability to Navaid Wing Leveller/Autopilot.
Regards
Gerry
Gerry Holland
mailto://gnholland@onetel.com
+44 7808 402404
Europa XS 384
G-FIZY
The greatest enjoyment from existence is living dangerously....
Friedrich Nietzsche
Message 7
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--> AeroElectric-List message posted by: "Tinnemaha" <Tinnemaha@charter.net>
Hello List,
Thank You (especially Bob Nuckolls) for the responses to my question about de-rating
mini switches a while back......the answers made great sense and convinced
me what a great resource this list is. I will be contributing a touch of $
to the list soon.
I am in the process of re-designing the panel for my Kitfox....basically going
to use fuses instead of breakers and changing from a panel mounted GPS/Com to
a comm & a hand held GPS (mainly for economic reasons). Could You please recommend
the Comm & GPS that will give me the best value as well as the best place
to get them? I'm assuming a Terra Comm & Garmin GPS but recommendations from
experienced people will be very helpful.
Thanks,
Grant
Message 8
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--> AeroElectric-List message posted by: "J. Oberst" <joberst@cox-internet.com>
During building my Glasair, I've had many courageous incidents.... like
cutting out the fuselage for the wing and the horizontal stab... and also
drilling for the EGT probes.
Before doing mine, I of course mounted the exhaust system on the engine. I
looked at other installations, and discovered that generally the probes are
mounted on the inside of the pipes - toward the engine. That way, you are
in complete control of the clearances, because anything that could cause
interference is already there. The wire routing is easier, too.
Also, I discovered that the holes were pretty easy to drill.
Good luck.
Jim Oberst
----- Original Message -----
From: "Julia" <wings97302@yahoo.com>
Subject: AeroElectric-List: EGT PROBES
> --> AeroElectric-List message posted by: Julia <wings97302@yahoo.com>
>
>
> Any pointers on mounting EGT probes - i'm having a hard time finding the
courage to drill the holes in my $1,200 4-into-1 stainless exhaust sytem?
>
> If a probe were mounted so it stuck straight out - would that hit the
cowl?? is there plenty of clearance so any direction is ok?
>
> thanks
>
>
> ---------------------------------
>
>
Message 9
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--> AeroElectric-List message posted by: Jerry2DT@aol.com
Listers...
I too, feel that the least we can do is to support Bob so that it is somewhat
of a two-way street. I'll buy everything I can from him, after all the
excellent advise he dispenses in an ongoing effort here. We are way too
fortunate to have him here to help us.
Jerry Cochran
Message 10
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| Subject: | Altitude control |
--> AeroElectric-List message posted by: John Loram <johnl@loram.org>
Don't know what you consider to be "reasonable", but Trutrak
(http://www.trutrakflightsystems.com/index.html) has just announced a $1600
(?) standalone altitude hold, complete with servo. Looks like it's not on
their web site yet.
-john-
john@loram.org
www.loram.org
-----Original Message-----
From: Gary Casey [mailto:glcasey@adelphia.net]
Subject: AeroElectric-List: Altitude control
--> AeroElectric-List message posted by: "Gary Casey" <glcasey@adelphia.net>
<<> I've got plans for
> a super sensitive, temperature compensated pressure
> transducer that gives me +/- 20 foot accuracy to
> 60,000 feet and better than 1% accuracy for pitot
> pressures to 300 kts.
Does this mean we will be seeing a reasonably accurate, affordable altitude
control
device in
the near future?>>
Pardon me if I don't hold my breath for this one. 20 feet of accuracy at
60,000 equates to a maximum error of .00098 psi, or 0.007% of full scale, an
accuracy not attainable by even laboratory grade sensors. At sea level 20
feet equates to 0.01 psi or 0.07% of full scale, within reach of high-end
pressure sensors, but only over a very limited temperature range. Typical
autopilots (S-TEC) use the altitude encoder with 100-foot resolution and
about 100-foot accuracy to capture an altitude, but then use a fairly
rudimentary pressure sensor to hold that altitude. A typical sensor for
that application (which we build) is about 1 to 2% accuracy over a wide
temperature range. Any modern manifold absolute pressure (MAP) sensor would
be easily capable of doing the altitude hold feature of an autopilot. I'm
using an standard Chrysler MAP sensor right now for that purpose. If one
were to use a 1% MAP sensor at a retail cost of $20 to $50 for altitude
capture the accuracy would be 274 feet at sea level and 524 feet at 20,000
feet altitude. However, the REPEATABILITY of an automotive MAP sensor over
a limited temperature range will be about 0.1% so if one were willing to do
a one-time setting of the error you could have an altitude capture error
about 1/10 of the above, or 27 feet at sea level and 52 feet at 20,000 feet.
I would think that would be about as accurate as we care about and all that
can be had today with sensors built in quantities of several million a year.
Gary Casey
Message 11
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--> AeroElectric-List message posted by: "Tinnemaha" <Tinnemaha@charter.net>
I'm in the (very frustrating) process of designing an electrical system for my
first experimental (Kitfox w/ Lyc O-235):
I'm confused about over voltage protection devices(for alternators):
I understand that their basic purpose is to protect the electrical system if
the voltage output gets too high, but isn't that the function of any other type
of cirquit protection device (fuses, breakers, fusible links)? I'm planning
on installing a 35 amp fusible link between the alternator and the main bus.
Does that only protect against over-amperage? I saw the 'crow-bar' type of
OV protection devices from B&C on the web site - does that get installed between
the alternator and the fusible link?
Any comments or clarifications would be helpful
Thanks,
Grant
Message 12
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| Subject: | Electronic Ignition? |
--> AeroElectric-List message posted by: "Tinnemaha" <Tinnemaha@charter.net>
I am putting a Lycoming O-235 that was re-built by a local & reputable FBO on my
Kitfox. I saw the engine run on a test stand & paid an independent mechanic
check it out before I bought it - I feel I got a great deal but am not sure what
condition the Slick Magnetos are in. I have a general idea that it would
be good to replace the mags with electronic ignition some day.
Could You please advise about the cost/benefit of re-building/re-placing mags verses
installing electronic ignition? (Money IS an issue for me)
Thanks,
Grant
Message 13
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| Subject: | Re: Electronic Ignition? |
--> AeroElectric-List message posted by: "J. Oberst" <joberst@cox-internet.com>
If you have working mags, replacing them with electronic ignition is
generally a money-loser. People do it for performance or to feel that they
have a high-tech engine. You should be able to decide whether the mags need
service by how much time is on them. I think Slick recommends rebuilds in
500 hours, but I'm not sure - you'd have to check, and most people leave
them much longer than this.
Jim Oberst
----- Original Message -----
From: "Tinnemaha" <Tinnemaha@charter.net>
Subject: AeroElectric-List: Electronic Ignition?
> --> AeroElectric-List message posted by: "Tinnemaha"
<Tinnemaha@charter.net>
>
> I am putting a Lycoming O-235 that was re-built by a local & reputable FBO
on my Kitfox. I saw the engine run on a test stand & paid an independent
mechanic check it out before I bought it - I feel I got a great deal but am
not sure what condition the Slick Magnetos are in. I have a general idea
that it would be good to replace the mags with electronic ignition some day.
>
> Could You please advise about the cost/benefit of re-building/re-placing
mags verses installing electronic ignition? (Money IS an issue for me)
>
>
Thanks,
>
Grant
>
>
Message 14
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| Subject: | Re: RE: Microair radio |
--> AeroElectric-List message posted by: Rino <lacombr@nbnet.nb.ca>
Anyone have information about the new radio similar to the Microair.
I am looking for a supplier of this radio
Rino
Message 15
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| Subject: | Re: RE: Microair radio |
--> AeroElectric-List message posted by: RSwanson <rswan19@comcast.net>
Michael Coates has one. May be the one you're thinking of.
http://www.mcp.com.au/xcom760/
R
----- Original Message -----
From: "Rino" <lacombr@nbnet.nb.ca>
Subject: Re: AeroElectric-List: RE: Microair radio
> --> AeroElectric-List message posted by: Rino <lacombr@nbnet.nb.ca>
>
> Anyone have information about the new radio similar to the Microair.
> I am looking for a supplier of this radio
>
> Rino
>
>
>
>
>
>
Message 16
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| Subject: | Re: RE: Microair radio |
--> AeroElectric-List message posted by: Rino <lacombr@nbnet.nb.ca>
Thanks, I think that is the one I am looking for.
RSwanson wrote:
>
> --> AeroElectric-List message posted by: RSwanson <rswan19@comcast.net>
>
> Michael Coates has one. May be the one you're thinking of.
> http://www.mcp.com.au/xcom760/
> R
>
> ----- Original Message -----
> From: "Rino" <lacombr@nbnet.nb.ca>
> To: <aeroelectric-list@matronics.com>
> Subject: Re: AeroElectric-List: RE: Microair radio
>
> > --> AeroElectric-List message posted by: Rino <lacombr@nbnet.nb.ca>
> >
> > Anyone have information about the new radio similar to the Microair.
> > I am looking for a supplier of this radio
> >
> > Rino
> >
> >
> >
> >
> >
> >
>
--
Message 17
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| Subject: | Re: Altitude control |
--> AeroElectric-List message posted by: ScramIt@aol.com
We should be installing our EZtrims in a Cozy MKIV and a Glastar by the end
of the month. My Europa box is built, but alas my Europa is not. I'll let you
know how flight tests go.
SteveD.
http://homepage.mac.com/sdunsmuir/Europa.html
Message 18
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| Subject: | Re: Electronic Ignition? |
--> AeroElectric-List message posted by: "Jim Jewell" <jjewell@telus.net>
Hello Grant,
E.I. pluses:
Less overall system weight.
Better GPH. at cruise altitude 6000' and up.
Less failure prone.
Lower spark plug costs.
lower overhaul costs.
More power if that is your focus over GPH.
Smoother idle.
Starting improvements.
E.I. negatives:
In the field repair service less convenient.
Warranty and performance issues with Hartzell Co.constant speed props.
-
Keep in mind that the replaced mag can be sold to cover some of the initial
EI. cost.
You can also just run what you have until a pricey service or repair becomes
an issue.
Jim in Kelowna
----- Original Message -----
From: "Tinnemaha" <Tinnemaha@charter.net>
Subject: AeroElectric-List: Electronic Ignition?
> --> AeroElectric-List message posted by: "Tinnemaha"
<Tinnemaha@charter.net>
<snip> Could You please advise about the cost/benefit of
re-building/re-placing mags verses installing electronic ignition? (Money IS
an issue for me)
Thanks,
Grant
Message 19
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| Subject: | Re: OV Protection |
--> AeroElectric-List message posted by: Julia <wings97302@yahoo.com>
Grant:
make sure you get the Aeroconnection book - and read it from cover to cover - then
follow Z-11 I think it is - that seems to be a pretty good layout - that's
what i'm following. once the basic layout is down, you should find it easy to
wire everything up.
good luck
Tinnemaha <Tinnemaha@charter.net> wrote:--> AeroElectric-List message posted by:
"Tinnemaha"
I'm in the (very frustrating) process of designing an electrical system for my
first experimental (Kitfox w/ Lyc O-235):
I'm confused about over voltage protection devices(for alternators):
I understand that their basic purpose is to protect the electrical system if the
voltage output gets too high, but isn't that the function of any other type
of cirquit protection device (fuses, breakers, fusible links)? I'm planning on
installing a 35 amp fusible link between the alternator and the main bus. Does
that only protect against over-amperage? I saw the 'crow-bar' type of OV protection
devices from B&C on the web site - does that get installed between the
alternator and the fusible link?
Any comments or clarifications would be helpful
Thanks,
Grant
---------------------------------
Message 20
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| Subject: | Fw: Spike-catcher diode failures |
--> AeroElectric-List message posted by: "KeithHallsten" <KeithHallsten@quiknet.com>
Here's a thread that's been going on the Velocity builder's list server. Food
for thought for all!
---- Original Message -----
From: Al Gietzen
Sent: Friday, March 14, 2003 11:55 AM
Subject: REFLECTOR: Speaking of diodes
It is obviously common practice to use diodes and Transient voltage suppressors
(TVS) to kill the backward inducted current from devices with coils (relays,
motors, etc.) to protect the contacts in switches and relys from arcing.
Have we also considered the consequences of these little jewels failing; especially
failing in a shorted condition; which, I believe is the most likely failure
mode.
I had installed a TVS (a P6KE27DICT TVS from Digikey rated 27v 600W) across
the coil on a battery contactor. It has been there for a year or two and has
worked well as I cycled the gear or whatever. Also in testing circuits I have
many times closed the contactor by touching an alligator clip from battery
- to the ground terminal of the coil for momentary closing, and was pleased to
note that there was little or no arcing. Until the other day, when I went to
do that and got a bunch of sparks. What! I put it on again and realized quickly
that I had a dead short and things were getting hot in a hurry. The TVS
had failed shorted.
In a typical circuit, the battery switch on your panel closes that contactor
coil circuit to ground. A shorted TVS, or diode, makes that an unprotected
short to ground, and I'd think could smoke some #22 awg pretty fast. What's
wrong with this picture? Are we assuming that these things don't fail?
Similarly; a shorted diode that you have across your trim motor relay would
cause the trim to run all the way to one extreme and stay there. Can you fly
and land your plane with full up or down trim? Could be be real tough, especially
if you haven't trimmed the trim spring to allow full travel in the opposite
direction with some hard pulling on the stick.
I have a bunch of the 1N4001 diodes that I planned using across small relays.
I think a diode across a contactor needs a higher current rating, but how
high? And how does one determine the rating required. Us electronically challenged
nuclear engineers, educated mostly before the advent of semiconductors,
want to know.
Thanks,
Al
----- Original Message -----
Al
You are correct, this had been a problem and has resulted in problems with general
and commercial aircraft. I could not find my notes for an IA conference in
early 90's but did find info in notes from a conference this year. AD 90 03
19 R1 required all spike suppression devices to be removed from a commercial
transport because of fire in the heater elements that was caused by the spike
diode that shorted the relay to ground. The FAA will not allow any electrical
system to be installed in an aircraft that has a spike suppression device across
the coil of a relay that is connected to a high current power source. The key
is "HIGH CURRENT".
On low-current systems it is still ok but as you noted this type of system will
almost always bypass the circuit breaker and burn something up. If using a spike
suppression device, try to use a transorb (Mosorb), try 1N6284A/ 1.5kE36A,
Motorola. Cost less than $1 and works much much faster. Remember, low current
only.
Johnny Thompson XLRG N5UP
----------------------------------------------
----- Original Message -----
Subject: Re: REFLECTOR: Speaking of diodes
It would be informative to connect the shorted diode to a piece of 22 ga mil spec
wire then apply 13 volts and see which melts first. I'll bet the diode burns
open before the insulation is damaged.
----- Original Message -----
From: Al Gietzen
To: reflector@tvbf.org
Sent: Saturday, March 15, 2003 5:58 PM
Subject: RE: REFLECTOR: Speaking of diodes
Well; I did just that. Based on two tests, you lose your bet 50% of the time.
I first did the test on the TVS that had failed short the other day. Recall
that it had heated pretty seriously before I opened the circuit. I put it between
two 10" lengths of #22 wire and applied 12 volts. The TVS opened in less
than a second and not much else happened.
I then failed a 1N4001 diode by passing a pulse of forward current exceeding
its rating. I then connected 12v in the other direction. The results were dramatic.
The diode and its leads were the first things that got red hot; followed
quickly by the #22 wire becoming red hot and essentially vaporizing all of
the tefzel insulation. A couple seconds more (at least it seemed that long) and
the insulation began melting on my #18 wire jumper; at which point I gave quick
tug on the alligator clips which pulled the diode apart.
My Conclusion: DO NOT put a diode across a relay where the relay coil is in a
circuit that closes to ground. In fact; look closely at any circuit where you
have used diodes to increase the life of the contacts in a switch or relay and
consider the consequences of a shorted diode.
Possible solution:
My son (who is not electronically challenged, and makes his living designing
microprocessors and other circuits, suggests the following:
There are two other "snubbing" approaches you can use which won't have a single
point failure.
1) Diode and resistor in series. Resistor value would be chosen to match resistance
of coil. Unlike the purely resistive snubbing which would place additional
drain on the battery, the diode will prevent the current from flowing through
the resistor in normal mode. The resistor protects your circuit in the
event of a diode failure, and still allows the relay to operate. In snubbing
mode, the current flows through the resistor and the diode.
2) Resistor and capacitor in series. With this approach, the capacitor is chosen
to "absorb" the energy from the coil. However, the circuit will now resonate.
The resistor is added to dampen the resonance. Choosing the values of
both the R and C would depend on the inductance of the coil, which is something
you probably don't know. So, there would be some trial and error involved
with choosing values.
I think approach #1 will work very well.
Sounds right to me. The resistance of the battery contactor coil is about 15
ohms. Put a 15 ohm resistor in series with the diode, and the current in the
rare event of the shorted diode would be less than an amp. Keep the resistor
in the open air where it can dissipate some heat. Typical 15 A relays have coil
resistance of about 150 Ohms. Put in a 150 Ohm resistor with your diode and
shorted current is limited to less than 0.1 amps. Not enough to drive your
trim motor.
Anyway; it makes sense to me not to risk myself and my plane in an effort to
prolong the life of the contacts in a relay. Failure of the relay is likely to
be inconsequential.
Best, Al
Message 21
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| Subject: | advanced aircraft electronics |
--> AeroElectric-List message posted by: "Larry Bowen" <Larry@BowenAero.com>
Can anyone offer an opinion on the antennas from advanced aircraft
electronics (http://www.advancedaircraft.com/)? I'm considering their
nav ant for installation in my RV-8 wing-tip.
-
Larry Bowen
Larry@BowenAero.com
http://BowenAero.com
2003 - The year of flight!
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