Today's Message Index:
----------------------
1. 12:05 AM - Re: How to test new circuits using battery and protect circuit? (Robert L. Nuckolls, III)
2. 03:00 AM - Re: ELT location (Carlos Trigo)
3. 06:27 AM - Re: D-sub connections (Robert L. Nuckolls, III)
4. 06:59 AM - Re: D-sub connections (Kevin Boddicker)
5. 08:06 AM - Re: Speaking of GPS ()
6. 10:20 AM - Re: Re: Speaking of GPS (Richard Girard)
7. 10:39 AM - Re: ELT location (Ed Holyoke)
8. 12:51 PM - GT-50 G-meter installation (Peter Pengilly)
9. 01:46 PM - Re: GT-50 G-meter installation (John Morgensen)
10. 01:48 PM - Compass problem (eddyfernan@aol.com)
11. 02:19 PM - Re: GT-50 G-meter installation (Peter Pengilly)
12. 03:27 PM - Re: Re: ELT location (John Cox)
13. 03:35 PM - [Fw: Re: Speaking of GPS . . .] (David M.)
14. 03:49 PM - Feedline Radiation in Composite Airplane (fiveonepw@aol.com)
15. 05:03 PM - Re: Feedline Radiation in Composite Airplane (jetboy)
16. 06:34 PM - Re: GPS Serial Data to Garmin GTX-327 Transponder (Brantel)
17. 08:34 PM - [Fw: Fw: Panda antics..........] (RScott)
18. 09:07 PM - Re: [Fw: Re: Speaking of GPS . . .]Thank you Yahoo! (David M.)
Message 1
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| Subject: | Re: How to test new circuits using battery and protect |
circuit?
At 01:10 PM 1/17/2009, you wrote:
>
>I have wired my wing lights and my heated pitot tube. I will soon
>be installing the wiring in the fuselage.
>My question is how do I power up and test circuits and/or systems
>from my battery and still have short protection? Is there a device
>or alternate power supply that I can use and be able to select some
>circuit breaker value to protect the wires?
Every "laboratory grade" power supply has an adjustable
current limit feature that can be used to power up
a system and dial-in whatever current limit you want.
Alternatively, make your first test of the system by
clipping a 10A fuse across the open battery contactor
with everything in the system turned OFF. If the
fuse doesn't pop, your fat wires are fine. From that
point on, you DO have short circuit protection in the
form of breakers/fuses installed for that purpose.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
Message 2
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Thank you very much, James.
That's exactly the kind of answer I needed!!
In a further comment, I am also waiting for decent prices on 406MHz
ELT's,
but AmeriKing has recently released the AK-451, with
<http://www.aircraftspruce.com/catalog/avpages/ameriKingpackages.php>
and
without
<http://www.aircraftspruce.com/catalog/avpages/ameriKingpackages.php>
GPS
(It=92s funny how they=92re already in Aircraft Spruce catalogue but not
in
AmeriKing website?!).
Unfortunately, the international (INT) version (I need it for Europe)
with
GPS seems not yet available, therefore I=92ll have to wait a little bit
longer.
However, together with 121.5, 243 and 406 MHz frequencies and GPS
position
transmission, this unit seems to have voice transmission as well, so it
looks that, beyond all other location recommendations (structural
attachment, directional position, less potential destructive place,
etc.),
one should install it in an easy reachable position inside the cabin.
Carlos
> -----Original Message-----
> From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-
> server@matronics.com] On Behalf Of James H Nelson
> Sent: s=E1bado, 17 de Janeiro de 2009 22:41
> To: aeroelectric-list@matronics.com
> Subject: AeroElectric-List: ELT location
>
>
> Carlos,
> I have a "9" with the slider canopy. I mounted my "required"
ELT
> on the frame just behind the pass. seat. I use a Ameri king (the
redish
> colored one) and using the fame as the main mount, I ran the antenna
back
> through it and mounted it to the top of the cover that encloses the
> rudder cable in the baggage compartment. This lets me remove the
whole
> unit easily if I need to in the future. Some day there will be a
> reasonable 406 mz unit and I will put it in the tail cone behind the
> baggage compartment. There are lots of problems with antenna
placement.
> First, there is a very good chance I will flip over. This places the
> antenna under the airframe. The rudder will protect the antenna to a
> point. That may break it off. I placed the antenna inside as my pix
> shows. Not the best but it will work. The very low power of the
> transmitter leaves much to be desired but its there. I have a PLB
that I
> carry in my survival vest. If I can get out or at least put the PLB
out
> side of the airframe, it has a built in gps so they can find me fairly
> quickly. I hope that gives you some ideas.
>
> Jim Nelson
> N15JN
> RV9-A
> ____________________________________________________________
> Free information - Learn about Wheel Chair options. Click now!
>
http://thirdpartyoffers.juno.com/TGL2141/fc/PnY6rw1lvVIEGFiAbDHEmzQDSCNQg
> CEqYbyo3hXmSwmEWNo3D5JLj/
Message 3
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| Subject: | Re: D-sub connections |
At 03:58 PM 1/17/2009, you wrote:
>Bob,
>Is there a comic book that explains how to make a d-sub crimp.
>How to use the tool, etc.
>I have looked over your site, no joy.
Never considered adding one. The use of the
tool is pretty easy to dope out by inspection.
If you have the right tool, there are no variables
of process or technique. This is about as artless
an activity as you can find in the field of
fabrication skills for building an airplane.
If you study the pins . . .
http://www.aeroelectric.com/Pictures/Connectors/D-Subminature/D-Sub_20AWG_Socket.jpg
http://www.aeroelectric.com/Pictures/Connectors/D-Subminature/D-Sub_20AWG_Pin.jpg
You can mate a couple of them as if they were
inside housings. In all cases, the smallest
diameter on a pin is gripped by springy
contacts within the socket. The open ends
of a mated pair always look the same, may have
an identifying set if color bands and
usually have an inspection hole.
Strip a piece of wire and insert the stripped
end into the wire grip end of a pin or socket.
Note whether the wire bottoms out in the pin
before the insulation hits. If the gap between
pin an insulation is more than say 0.050" (tiny)
then you've stripped off too much wire. If the
insulation touches, you've not stripped off
enough. Get that one piece of the "art" figured
out first.
I like to hold a stripped wire up, perch a pin
on the end and lower the tool over it. When fully
seated in the tool, squeeze.
When you've finished, the job looks something
like this:
http://www.aeroelectric.com/Pictures/Connectors/D-Subminature/D-Sub_4-quad-crimp.jpg
The punches in the tool should compress the
barrel right about mid-ships. Some of the lower
cost tools place the crimp too far back toward
the wire-grip opening. It CAN be pretty close
but never so close that you loose the bell-mouth
opening. You should be able to see strands in
the inspection hole . . . this assures you that
the strands extend all the way through the wire
grip and that internally, there's another
bell-mouth opening from which the strands
protrude.
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: D-sub connections |
Thanks Bob, for all you do!!!
Kevin Boddicker
Tri Q 200 N7868B
Luana, IA.
Do Not Archive
On Jan 18, 2009, at 8:24 AM, Robert L. Nuckolls, III wrote:
> <nuckolls.bob@aeroelectric.com>
>
> At 03:58 PM 1/17/2009, you wrote:
>> Bob,
>> Is there a comic book that explains how to make a d-sub crimp.
>> How to use the tool, etc.
>> I have looked over your site, no joy.
>
> Never considered adding one. The use of the
> tool is pretty easy to dope out by inspection.
> If you have the right tool, there are no variables
> of process or technique. This is about as artless
> an activity as you can find in the field of
> fabrication skills for building an airplane.
>
> If you study the pins . . .
>
> http://www.aeroelectric.com/Pictures/Connectors/D-Subminature/D-
> Sub_20AWG_Socket.jpg
>
> http://www.aeroelectric.com/Pictures/Connectors/D-Subminature/D-
> Sub_20AWG_Pin.jpg
>
> You can mate a couple of them as if they were
> inside housings. In all cases, the smallest
> diameter on a pin is gripped by springy
> contacts within the socket. The open ends
> of a mated pair always look the same, may have
> an identifying set if color bands and
> usually have an inspection hole.
>
> Strip a piece of wire and insert the stripped
> end into the wire grip end of a pin or socket.
> Note whether the wire bottoms out in the pin
> before the insulation hits. If the gap between
> pin an insulation is more than say 0.050" (tiny)
> then you've stripped off too much wire. If the
> insulation touches, you've not stripped off
> enough. Get that one piece of the "art" figured
> out first.
>
> I like to hold a stripped wire up, perch a pin
> on the end and lower the tool over it. When fully
> seated in the tool, squeeze.
>
> When you've finished, the job looks something
> like this:
>
> http://www.aeroelectric.com/Pictures/Connectors/D-Subminature/D-
> Sub_4-quad-crimp.jpg
>
> The punches in the tool should compress the
> barrel right about mid-ships. Some of the lower
> cost tools place the crimp too far back toward
> the wire-grip opening. It CAN be pretty close
> but never so close that you loose the bell-mouth
> opening. You should be able to see strands in
> the inspection hole . . . this assures you that
> the strands extend all the way through the wire
> grip and that internally, there's another
> bell-mouth opening from which the strands
> protrude.
>
>
> 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: Speaking of GPS |
The Garmin Edge 705
https://buy.garmin.com/shop/shop.do?pID=10885
is a very cool GPS unit intended for bicycle riders. It not only navigates, but
it also data logs your entire track covered, heart rate, and some other nifty
parameters for the entire trip!
All this data can be downloaded and then displayed on a Google satellite map,
and by clicking on points along the track, it will list the recorded data for
that point along the track!
I was driving home in my car after a long bike ride and forgot to turn off the
Garmin. When I got home I downloaded the data and it included all the data not
only from the ride but also from the drive home!
I wonder, if I ever got a bogus speeding ticket ("Officer, there is no way I was
going THAT fast...") if I could use my downloaded time/speed/location as evidence?
I can't wait for warm weather to see if I can data log a flight in my Evo!
Paul Siegel
Message 6
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| Subject: | Re: Speaking of GPS |
Paul, Yes, you could beat a ticket with the info from your GPS assuming you
came before a reasonable judge. A fellow in California had a GPS tracking
unit in his teenage son's car. Son got a ticket and Dad and son used the GPS
data to show that there was no speeding. The judge dismissed the case. Heard
about it on NPR last year.
Rick
do not archive
On Sun, Jan 18, 2009 at 9:54 AM, <psiegel@fuse.net> wrote:
>
> The Garmin Edge 705
>
> https://buy.garmin.com/shop/shop.do?pID=10885
>
> is a very cool GPS unit intended for bicycle riders. It not only
> navigates, but it also data logs your entire track covered, heart rate, and
> some other nifty parameters for the entire trip!
>
> All this data can be downloaded and then displayed on a Google satellite
> map, and by clicking on points along the track, it will list the recorded
> data for that point along the track!
>
> I was driving home in my car after a long bike ride and forgot to turn off
> the Garmin. When I got home I downloaded the data and it included all the
> data not only from the ride but also from the drive home!
>
> I wonder, if I ever got a bogus speeding ticket ("Officer, there is no way
> I was going THAT fast...") if I could use my downloaded time/speed/location
> as evidence?
>
> I can't wait for warm weather to see if I can data log a flight in my Evo!
>
> Paul Siegel
>
>
Message 7
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| Subject: | Re: ELT location |
James,
I tried last night but my message came through empty.
The way your ELT is mounted, the 'G' switch is oriented to starboard
instead of down. I think it would take a pretty unusual crash to
activate it. Mounted that way, it is unlikely to pass inspection, too.
You might want to rethink it.
Van's recommends and supplies kits for mounting behind the baggage
bulkhead to some pretty solid structure. That meets the ELT
manufacturer's specs and the FAA's as well. I know a guy who mounted his
to the baggage floor and zip tied the remote switch right too it. His
passed the DAR's scrutiny, OK.
Pax,
Ed Holyoke
James H Nelson wrote:
> Carlos,
> I have a "9" with the slider canopy. I mounted my "required" ELT
> on the frame just behind the pass. seat. I use a Ameri king (the redish
> colored one) and using the fame as the main mount, I ran the antenna back
> through it and mounted it to the top of the cover that encloses the
> rudder cable in the baggage compartment. This lets me remove the whole
> unit easily if I need to in the future. Some day there will be a
> reasonable 406 mz unit and I will put it in the tail cone behind the
> baggage compartment. There are lots of problems with antenna placement.
> First, there is a very good chance I will flip over. This places the
> antenna under the airframe. The rudder will protect the antenna to a
> point. That may break it off. I placed the antenna inside as my pix
> shows. Not the best but it will work. The very low power of the
> transmitter leaves much to be desired but its there. I have a PLB that I
> carry in my survival vest. If I can get out or at least put the PLB out
> side of the airframe, it has a built in gps so they can find me fairly
> quickly. I hope that gives you some ideas.
>
> Jim Nelson
> N15JN
> RV9-A
>
>
Message 8
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| Subject: | GT-50 G-meter installation |
Hi,
I'm installing a GT-50 G-meter in my airplane, my question is does
anyone
have one of these devices and have you switched it's power supply, or do
you
leave it on all the time?
The airplane is aerobatic has only an SD-8 topping up a 17ah PC680
battery.
The installation instructions suggest that the GT-50 is connected to
straight to the battery to keep the clock counting, it is suggested that
as
the current draw is so low it will never flatten the battery. Today I
measured the current draw which is about 6 mA, so the clock will draw
about
an amp hour per week (if my multi-meter is accurate). So, assuming the
battery is charged to 80% when I close the hangar door, the clock will
flatten the battery in 3 months. But how long will it take before the
battery does not have sufficient charge to start the engine (O-360
Lycoming)?
I expect that most flights will be 20 or 30 minutes so may only just
replace
what is use for starting, if I haven't flown for several weeks will I
find
that the battery just can't cope with losing an ah a week plus starting
the
engine? I don't expect the current drain when flying to be high,
EIS-4000,
Becker radio and Garmin transponder and GPS Pilot III GPS will draw
perhaps
2A, but if I forget to switch off the electric fuel pump there could be
only
2 or 3A available for battery charging. So should I switch the power to
the
GT-50 and accept that I will have to re-set the clock?
If anyone has any real world experience I would be interested to hear
from
you.
Regards, Peter
Message 9
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| Subject: | Re: GT-50 G-meter installation |
Why not just hard-wire the connector for a battery maintainer? Bob has
tested several and the Schumacker brand at Walmart was as good as any.
John Morgensen
Peter Pengilly wrote:
>
> Hi,
>
>
>
> I'm installing a GT-50 G-meter in my airplane, my question is does
> anyone have one of these devices and have you switched it's power
> supply, or do you leave it on all the time?
>
>
>
> The airplane is aerobatic has only an SD-8 topping up a 17ah PC680
> battery. The installation instructions suggest that the GT-50 is
> connected to straight to the battery to keep the clock counting, it is
> suggested that as the current draw is so low it will never flatten the
> battery. Today I measured the current draw which is about 6 mA, so the
> clock will draw about an amp hour per week (if my multi-meter is
> accurate). So, assuming the battery is charged to 80% when I close the
> hangar door, the clock will flatten the battery in 3 months. But how
> long will it take before the battery does not have sufficient charge
> to start the engine (O-360 Lycoming)?
>
>
>
> I expect that most flights will be 20 or 30 minutes so may only just
> replace what is use for starting, if I haven't flown for several weeks
> will I find that the battery just can't cope with losing an ah a week
> plus starting the engine? I don't expect the current drain when flying
> to be high, EIS-4000, Becker radio and Garmin transponder and GPS
> Pilot III GPS will draw perhaps 2A, but if I forget to switch off the
> electric fuel pump there could be only 2 or 3A available for battery
> charging. So should I switch the power to the GT-50 and accept that I
> will have to re-set the clock?
>
>
>
> If anyone has any real world experience I would be interested to hear
> from you.
>
>
>
> Regards, Peter
>
> *
>
>
> *
Message 10
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Hey guys,
I'm flying an RV9A slider. All of a sudden the center support bar on the roll bar?is
causing the compass which is near it, to read erratically (I've tried two
different compasses). Since the holes are drilled in the skin I'd like to keep
the compass in it's original location and not move it.
This is after 2 years of not having a problem. Can the center bar suddenly become
magnetized? What should I do to fix it?
__________________
Eddy Fernandez
RV9A
standard whiskey compass
Message 11
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| Subject: | GT-50 G-meter installation |
Hi John, I'm unlikely to have power in the hangar. Peter
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of John
Morgensen
Sent: 18 January 2009 21:45
Subject: Re: AeroElectric-List: GT-50 G-meter installation
Why not just hard-wire the connector for a battery maintainer? Bob has
tested several and the Schumacker brand at Walmart was as good as any.
John Morgensen
Peter Pengilly wrote:
Hi,
I'm installing a GT-50 G-meter in my airplane, my question is does
anyone
have one of these devices and have you switched it's power supply, or do
you
leave it on all the time?
The airplane is aerobatic has only an SD-8 topping up a 17ah PC680
battery.
The installation instructions suggest that the GT-50 is connected to
straight to the battery to keep the clock counting, it is suggested that
as
the current draw is so low it will never flatten the battery. Today I
measured the current draw which is about 6 mA, so the clock will draw
about
an amp hour per week (if my multi-meter is accurate). So, assuming the
battery is charged to 80% when I close the hangar door, the clock will
flatten the battery in 3 months. But how long will it take before the
battery does not have sufficient charge to start the engine (O-360
Lycoming)?
I expect that most flights will be 20 or 30 minutes so may only just
replace
what is use for starting, if I haven't flown for several weeks will I
find
that the battery just can't cope with losing an ah a week plus starting
the
engine? I don't expect the current drain when flying to be high,
EIS-4000,
Becker radio and Garmin transponder and GPS Pilot III GPS will draw
perhaps
2A, but if I forget to switch off the electric fuel pump there could be
only
2 or 3A available for battery charging. So should I switch the power to
the
GT-50 and accept that I will have to re-set the clock?
If anyone has any real world experience I would be interested to hear
from
you.
Regards, Peter
href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.
matro
nics.com/Navigator?AeroElectric-List
href="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
ontri
bution
Message 12
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| Subject: | Re: ELT location |
There is an old Van builder's Tale of the instructions for installation
of an "effective" ELT and rigging of the antennae with proper ground
plane. If it annunciates at all, from a few feet away, then it must be
compliant. We check the battery life, confirm it annunciates from a few
feet and they fly for another year.
Most builders install the device to comply with a requirement in a
written document that one must be onboard. Most ELTs do not emit a
proper signal and few builders care to research why.
I dropped by ARTEX last week to query them on my understanding of RF
transmission signals (in the 121 to 406 range) and they confirmed that
most ELTs are installed for looks, not for their intended function of
timely location. Maybe that is why the location of downed aircraft
receive the response they do. It could be the non-activation of the
switch, it could be that cute, hidden antenna.
Ground planes below the skin of the aircraft are one false tale,
Installation of an antenna next to a rigid structure is another. Lets
all agree we are doing the installation for compliance, not function and
that aethetics plays a big role in not doing it correctly. I
acknowledge that sliders affect the logic of sound antenna placement.
My understanding is that the RF signals don't care one whit about any of
that.
Now getting into Canada next month, now that is a meaningful question.
John Cox
do not archive
________________________________
From: owner-aeroelectric-list-server@matronics.com on behalf of
bcollinsmn
Sent: Sat 1/17/2009 7:14 AM
Subject: AeroElectric-List: Re: ELT location
<bob@rvbuildershotline.com>
We also kicked this around on the RV List in november. I don't have an
exact link but I referenced the discussion here:
http://rvbuildershotline.com/archives/2008/20081122.html
The original question I had, however, wasn't so much about the unit, it
was about the antenna. Many RVers tuck it around the rollbar, which
seemed to preclude a decent ground plane to me (if I understand ground
plane correctly).
The general consensus seemed to be, don't worry about it, it's not going
to work anyway, which seemed an odd position for people who are so
meticulous about the possibility of corrosion rotting their metal
airplanes in record time or any of the other million things with little
chance of happening that we obsess over. [Laughing]
Here's what I ended up doing, by the way.
http://rvnewsletter.blogspot.com/2008/11/installing-heres-where-my-remain
s-are.html
I had intended to run the antenna up a bulkhead support as indicated in
that latter link and that have the antenna up top just afte of another
bulkhead. Since then, i've bought a Dynon D100 and it recommends the
remote compass in that same location. So now I'm wondering if the
antenna will interfere with the th Dynon magnetometer?
--------
Bob Collins
St. Paul, Minn.
RV-7A (#&^ fiberglass!)
http://rvbuildershotline.com <http://rvbuildershotline.com/>
Day job:
http://minnesota.publicradio.org/collections/special/columns/news_cut/
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=225286#225286
Message 13
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| Subject: | Re: Speaking of GPS . . .] |
Message 14
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| Subject: | Feedline Radiation in Composite Airplane |
I'm trying to help a builder kill the dragon in the subject line-
Specifics: Garmin SL-30/40 with RG-400 to dipole on vertical stab spar
immediately in front of rudder, terminated with ring
connectors/screws/nuts. Coax terminated at radio using the supplied 90
deg. Garmin/Apollo fitting and runs with other wiring through center
floor tunnel to rear of plane, passing within about 12" from pitch
servo. Dipole is two aluminum bars, 1/2"x1/16"x20" long for each
element (I know this is a bit short- packaging issues. Optimum would
be about 44" overall length, I believe)
On com transmission, several systems are affected- Ray Allen trim LEDs
dim, indicated EGT/CHT temps rise (EIS), and most excitingly, the
autopilot (TruTrak) will occasionally re-direct the aircraft if
engaged, usually in a pitch-up of variable amounts depending on
frequency transmitting on. Usually worse at lower com freqs.
My own research (Wikipedia has a pretty good article on dipole
antennas(ae?) with several balun examples at end of article:
http://en.wikipedia.org/wiki/Dipole_antenna ) indicates the coax is
radiating lots of nasties off the shield, which I assume is making the
mischief.
Material from the Aeroelectric site (
http://www.aeroelectric.com/articles/BALUN/Balun_Fabrication.html )
describes a balun for nav- is this same approach suitable for com?
We've tried several ferrite ring arrangements, clamped around coax at
various locations, rings near the antenna end etc. Most effective has
been using a "ring", actually a small block that has two parallel holes
through it- the center conductor at the antenna end is passed through
one hole and back through the other in a tight "U" turn then connected
to the element. I suspect this is helping simply by reducing the
overall power output as it warms to the touch after a few transmissions
by absorbing some of the RF energy in the conductor?
A complicating factor may be that the rudder is attached by a contiuous
stainless steel hinge pin that parallels the antenna full-length a bit
over one inch away from it, but even with this pin removed, ground
testing does not seem to indicate much of a change in the symptoms.
Perhaps separating the upper and lower half of this pin and connecting
the coax to them as the antenna elements might be a neat experiment?
Also read
http://www.aeroelectric.com/articles/Morris_Com_Loop_Antenna.pdf and
curious if anyone can comment. This would fit into the tailcone
nicely, but place the antenna loop within about 12-14" of the
magnetometer and pitch servo.
Any advice/insight/suggestions appreciated!
Mark
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| Subject: | Re: Feedline Radiation in Composite Airplane |
At least one of the elements should be close to 24" so if you can extend the length
of the lower one - it does not matter whether its laid over by 90 degrees
or zig zag along the length to make room.
as you have found ferrites on the actual conductor will not work well. You may
need 2 or 3 ferrites over the coax cable at the dipole end to decouple the cable
from being a radiator. Your best friend here will be a reflectometer or someone
who has one and knows how to use it. Otherwise known as SWR meter or directional
wattmeter like Bird model 43 or a simpler example for the amateur radio
2 meter band.
The rudder hinge may also be a problem if it is longer than 24' and too close to
the antenna. i would not try to use it as a radiator unless you know that the
composite resins will not burn up from the heat. I do assume the composite is
f/glass, not carbon?
Its also possible for the instruments and servos to be getting interference directly
from a properly connected antenna, if it is situated too close - on some
certified aircraft I've worked with that can be as much as 10' away.
Once the antenna VSWR has been confirmed in limits across the frequency range
(certified antennas often incorporate a 12.5 ohm resistor inline to achieve
this) you can go chasing affected servos and instruments to add ferrites to these,
as a last resort.
Ralph
--------
Ralph - CH701 / 2200a
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=225563#225563
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| Subject: | Re: GPS Serial Data to Garmin GTX-327 Transponder |
Matt,
If your goal is to get the 327 to turn go in and out of standby automatically,
you can do this by using a pressure switch on your pitot/static system and connect
that to the squat switch input of the 327. Others have done this and report
it works great.
You must configure the 327 to use the squat switch..
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=225579#225579
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| Subject: | [Fwd: Fw: Panda antics..........] |
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| Subject: | Re: Speaking of GPS . . .]Thank you <Censored> |
Yahoo!
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