Today's Message Index:
----------------------
1. 01:21 AM - Re: Help needed: continued strobe noise & weak radio (FLYaDIVE@aol.com)
2. 05:09 AM - Re: Help needed: continued strobe noise & weak radio (luckymacy@comcast.net (lucky))
3. 05:09 AM - Re: Help needed: continued strobe noise & weak (Ken)
4. 05:12 AM - Re: Help needed: continued strobe noise & weak radio (luckymacy@comcast.net (lucky))
5. 06:56 AM - Landing lights & relays (tomcostanza@comcast.net)
6. 06:56 AM - Hall effect amp meter telling the truth? (Duane Wilson)
7. 07:19 AM - VM1000 light system failure (Ralph E. Capen)
8. 08:22 AM - Figure Z-7 (Michael Burson)
9. 09:00 AM - Re: Help needed: continued strobe noise & weak radio (Brian Lloyd)
10. 09:45 AM - Re: Landing lights & relays (Doug Windhorn)
11. 11:23 AM - Re: Landing lights & relays (Ken)
12. 12:27 PM - Re: Hall effect amp meter telling the truth? (Ken)
13. 12:42 PM - Re: VM1000 light system failure (Harry Manvel)
14. 12:48 PM - Re: Hall effect amp meter telling the truth? (Hopperdhh@aol.com)
15. 02:16 PM - Re: Grounding lugs (John McMahon)
16. 02:16 PM - Re: Grounding lugs (John McMahon)
17. 02:28 PM - Re: Grounding lugs (Hopperdhh@aol.com)
18. 02:52 PM - Re: Grounding lugs (Brian Lloyd)
19. 03:11 PM - Re: VM1000 light system failure (Ralph E. Capen)
20. 03:43 PM - Re: Landing lights & relays (tomcostanza@comcast.net)
21. 03:45 PM - BatteryLink ACR (Alex Balic)
22. 03:49 PM - Re: Landing lights & relays (tomcostanza@comcast.net)
23. 04:56 PM - Re: BatteryLink ACR (Brian Lloyd)
24. 06:30 PM - Re: Help needed: continued strobe noise & weak radio (luckymacy@comcast.net (lucky))
25. 07:14 PM - Re: Help needed: continued strobe noise & weak radio (Hopperdhh@aol.com)
26. 07:32 PM - braided bonding straps (Robert G. Wright)
27. 07:59 PM - Re: microphone noise (Ken)
28. 08:23 PM - Re: microphone noise (Charlie England)
29. 08:50 PM - Re: Help needed: continued strobe noise & weak radio (europa flugzeug fabrik)
30. 08:53 PM - Main bus wire feed (Steve James)
31. 08:57 PM - Re: Help needed: continued strobe noise & weak radio (europa flugzeug fabrik)
32. 09:02 PM - Re: Help needed: continued strobe noise & weak radio (europa flugzeug fabrik)
33. 10:51 PM - Re: Re: Help needed: continued strobe noise & weak radio (B Tomm)
Message 1
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Subject: | Re: Help needed: continued strobe noise & weak radio |
--> AeroElectric-List message posted by: FLYaDIVE@aol.com
In a message dated 7/15/06 10:05:43 PM Eastern Daylight Time,
luckymacy@comcast.net writes:
=========================================
Dear UN-Lucky:
Reading your post you seem to have answered your own questions. I have
inserted my comments within the body of your post. Please read on ...
> I have two "comm" issues that I haven't been able to debug to completion
yet.
> I'm using an Xcom 760 radio with their pre-made harness.
>
> 1) I still hear my strobes in my headset even when they are grounded with
> the radio ground and even when I put power noise filters on. However, the
> Radio Shack noise filters reference on Bob's web site were reported to me
to
> be no longer carried by them. So I used the only ones I could find locally
> which were sold by Pep Boys and the capacitor was 4700 uF instead of 2200
uF
> like Radio Shack apparently was.
- - - - - - - - - -
[Barry] - Strobe ground and Radio ground? I'm not sure what you are
referring to here. Can you elaborate a bit more?
BUT, if you are talking about using a SHIELDED wire as your ground ... The
shield should be grounded ONLY at the STROBE and you should use two conductor
and a shield wire.
As for the value of the capacitor, in 99.9% of the noise cases concerning a
DC circuit [our planes] the bigger the value the better. I really doubt if the
filter was designed ONLY for a specific frequency
------------------------------------------------------------------------------
-------------
>
> More specifically, the strobe noise is relatively faint until I select the
> Push to Talk button. Then it gets pretty loud. Some feedback going on
there.
> Looking for ideas from this list.
- - - - - - - - - - -
[Barry] Yup, sure sounds like the Ground for the PTT is the same Ground for
the Strobe. Here is where a problem may exist. Reading from either side of
the PTT to ground should NOT show continuity. This is a general statement, each
radio may be different but you would want to check this out and make sure the
PTT runs all the way back to the radio and NOT to A/C ground.
-----------------------------------------------------------------------------
>
> Should the capacitor specs have made a big difference on the effectiveness
> overall of the noise filter? It made no measurable difference regardless
of
> whether I installed it just before the radio or out at the strobe's power
> supply just before the AC +14v entered the power supply. I even reversed
> direction of the filter and it didn't matter one iota. Really bummed out
> about this turn of events since I thought they'd at least have made some
> observable difference based upon stuff in the archives.
- - - - - - - - - -
[Barry] - QUESTIONS:
How many leads does the filter have?
What are they labeled?
Most filters will have three of four leads. They may be: (4 lead) Pos & Neg
INPUT with Pos & Neg OUTPUT. Or, (3 lead) Pos & Neg INPUT with a Pos OUTPUT
{common Ground/Neg}.
The filter should go ON the device that is making the noise ... STROBE.
But, you have to go back and check how you hooked up the GROUNDS.
I'm betting that:
1 - The filter is not right next to the strobe.
2 - The power leads are not shielded.
3 - The ground goes all the way back to the area of the radios.
------------------------------------------------------------------------------
-
> 2) The second overall problem is that the radio still is reported to me
by
> other pilots as weak when I get much beyond a couple of miles and breaks up
> in the pattern a lot. I'm guessing it's because I can't put out enough
> consistent power to break their squelch consistently. When on the actual
> ground taxiing around, if there's a crown or "hill" between me and another
> airplane on the ground forget it. They can't hear me or vice a versa.
>
> When I check my radio with a handheld on the ground I seem to be just fine
> for the relatively close distances I've tried even when the plane is inside
> an open hangar and come in just as loud on the hand held as anyone else is.
> It also doesn't matter whether or not the strobes are powered on or not as
> far as whether or not the range/strength improves. ie, even with them off
> the lack of range doesn't improve.
>
> I swapped the cable between the radio and the antenna and it made no
> difference. I bought my antenna from Van's but didn't do any kind of post
> install test besides checking it out with my comm radio and a hand held and
> it seemed fine at the time...
- - - - - - - - - - - -
[Barry] - What kind of antenna are you using and where is it mounted?
------------------------------------------------------------------------------
-------
> Instead of using RG-58 I bought two pre-made RG-400 cables. What should
the
> center conductor's resistance read end to end? ~58 Ohms, right? My actual
> reading bounces all over the place no matter how stable I am in trying to
> read it. Strange. Also, there doesn't seem to be a short between the
center
> conductor and the plug itself when I check it with a multimeter so I'm
> guessing the plugs were installed correctly.
>
> Things I have left to try is just buy a pre-made 12' RG-58 cable from
radio
> shack and try it instead of the RG-400 cables. Also, I don't have a spare
> comm antenna but I think RS carries a replacement 800 Mhz scanner antenna
> with the right BNC connector that I can just temporarily use just to see if
> makes any difference at all.
- - - - - - - - - - - - - - - -
[Barry] - YOU just answered your own question. The RESISTANCE of a COAX when
disconnected from both ends should read OPEN _ INFINITY between center
conductor and shield. It should read SHORT_ ZERO between one end shield and the
other end shield. It should also read SHORT_ ZERO between one end center
conductor to other end center conductor.
As for the COAX, RG-400 is 75 ohm impeadance cable it is also a quad shield
cable a VERY good cable but not suited for our needs. We should be using RG-58
or RG-58A/U. It works for us very well. Oh, notice I used the term
IMPEDANCE. This is an AC resistance and is NOT measured with an OHM Meter.
Concerning the RG-800 .... I am not familiar with it. RG-58 is what you need
to use.
As for the Radio Shack (Real $hit) pre-made COAX stay away from it. I have
seen so many problems in their assembly, wrong coax, poor connections and
CRIMPS! You do not want a crimped coax.
NO self-respecting RF Man will accept a CRIMPED coax.
Barry
"Chop'd Liver"
Message 2
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Subject: | Re: Help needed: continued strobe noise & weak radio |
My answers and corrections to your wrong guesses/assumptions below:
-------------- Original message --------------
> --> AeroElectric-List message posted by: FLYaDIVE@aol.com
>
> In a message dated 7/15/06 10:05:43 PM Eastern Daylight Time,
> luckymacy@comcast.net writes:
> ==========================================
> Dear UN-Lucky:
>
> Reading your post you seem to have answered your own questions. I have
> inserted my comments within the body of your post. Please read on ...
>
>
> > I have two "comm" issues that I haven't been able to debug to completion
> yet.
> > I'm using an Xcom 760 radio with their pre-made harness.
> >
> > 1) I still hear my strobes in my headset even when they are grounded with
> > the radio ground and even when I put power noise filters on. However, the
> > Radio Shack noise filters reference on Bob's web site were reported to me
> to
> > be no longer carried by them. So I used the only ones I could find locally
> > which were sold by Pep Boys and the capacitor was 4700 uF instead of 2200
> uF
> > like Radio Shack apparently was.
> - - - - - - - - - -
> [Barry] - Strobe ground and Radio ground? I'm not sure what you are
> referring to here. Can you elaborate a bit more?
Lucky: My 2 strobe power supplies are installed at the wing tip and grounded to
the wing spar locally. Moving the grounds to back in the area where the rest
of my electronics were grounded including the XCOM radio didn't have any affect.
Also, disconnecting one strobe's power supply at a time didn't show that just one
was the culprit. They were both equal contributors. Installing the audio
noise filters out at the wing tips on the 14vdc input line just prior to the strobe
power supply had no affect. Installing one of those audio noise filters
(a plastic box with an inductor and a capacitor) on the 14vdc input line to the
xcom radio itself also had no affect.
BTW, after I originally bought and installed the Xcom radio, they revised their
drawing and FAQ section to REQUIRE owners install a 22,000 uF cap betwee the
xcom and it's power source near the radio. I didn't do that. Couldn't locally
find such cap.
> BUT, if you are talking about using a SHIELDED wire as your ground ... The
> shield should be grounded ONLY at the STROBE and you should use two conductor
> and a shield wire.
> As for the value of the capacitor, in 99.9% of the noise cases concerning a
> DC circuit [our planes] the bigger the value the better. I really doubt if the
> filter was designed ONLY for a specific frequency
> ------------------------------------------------------------------------------
Lucky: I used Van's pre-made wiring kit but I don't recall if the wiring to the
strobes was shielded or not. I'll check on that today to see if I or Van's
made a mistake because there is NO evidence shielded wiring was used for the strobe
power supply. It's been a long time since I hooked that up originally and
haven't looked at that angle yet so details are very fuzzy. The noise filter
was marketed to address noise introduced into radios when the car's engine RPM
is increased. But pulling its case open revealed it's just the same 3 wire
setup that Radio Shack was selling for while but with a different cap rating.
> -------------
> >
> > More specifically, the strobe noise is relatively faint until I select the
> > Push to Talk button. Then it gets pretty loud. Some feedback going on
> there.
> > Looking for ideas from this list.
> - - - - - - - - - - -
> [Barry] Yup, sure sounds like the Ground for the PTT is the same Ground for
> the Strobe. Here is where a problem may exist. Reading from either side of
> the PTT to ground should NOT show continuity. This is a general statement, each
> radio may be different but you would want to check this out and make sure the
> PTT runs all the way back to the radio and NOT to A/C ground.
> -----------------------------------------------------------------------------
Lucky: I'll check it out today. The original PTT switch came pre-wired with the
radio harness but I cut it off to use a different switch already installed
in my grip but just mirrored the pre-made setup.
> >
> > Should the capacitor specs have made a big difference on the effectiveness
> > overall of the noise filter? It made no measurable difference regardless
> of
> > whether I installed it just before the radio or out at the strobe's power
> > supply just before the AC +14v entered the power supply. I even reversed
> > direction of the filter and it didn't matter one iota. Really bummed out
> > about this turn of events since I thought they'd at least have made some
> > observable difference based upon stuff in the archives.
> - - - - - - - - - -
> [Barry] - QUESTIONS:
> How many leads does the filter have?
> What are they labeled?
> Most filters will have three of four leads. They may be: (4 lead) Pos & Neg
> INPUT with Pos & Neg OUTPUT. Or, (3 lead) Pos & Neg INPUT with a Pos OUTPUT
> {common Ground/Neg}.
> The filter should go ON the device that is making the noise ... STROBE.
> But, you have to go back and check how you hooked up the GROUNDS.
> I'm betting that:
> 1 - The filter is not right next to the strobe.
> 2 - The power leads are not shielded.
> 3 - The ground goes all the way back to the area of the radios.
> ------------------------------------------------------------------------------
Lucky: Filter has 3 leads. A postive IN, a Positive OUT and a ground lead coming
from the same physical side off the box as the Positive OUT lead. It was
installed literally adjacent to the strobes power supply's input voltage matching
the filter's instructions with no affect and I reversed the filters Positive
In/Out leads just for grins but again it made zero difference. I put in on
just before the radio too and it also made no difference. The directions that
came with it were assuming you were going to install it between a car radio
and it's input voltage to clean up the input voltage. Not somewhere else near
the actual source of "noise".
> -
> > 2) The second overall problem is that the radio still is reported to me
> by
> > other pilots as weak when I get much beyond a couple of miles and breaks up
> > in the pattern a lot. I'm guessing it's because I can't put out enough
> > consistent power to break their squelch consistently. When on the actual
> > ground taxiing around, if there's a crown or "hill" between me and another
> > airplane on the ground forget it. They can't hear me or vice a versa.
> >
> > When I check my radio with a handheld on the ground I seem to be just fine
> > for the relatively close distances I've tried even when the plane is inside
> > an open hangar and come in just as loud on the hand held as anyone else is.
>
> > It also doesn't matter whether or not the strobes are powered on or not as
> > far as whether or not the range/strength improves. ie, even with them off
> > the lack of range doesn't improve.
> >
> > I swapped the cable between the radio and the antenna and it made no
> > difference. I bought my antenna from Van's but didn't do any kind of post
> > install test besides checking it out with my comm radio and a hand held and
> > it seemed fine at the time...
> - - - - - - - - - - - -
> [Barry] - What kind of antenna are you using and where is it mounted?
> ------------------------------------------------------------------------------
It's one of the bent which antennas that Van's sells. Don't remember the brand.
Will look it over again today.
> -------
> > Instead of using RG-58 I bought two pre-made RG-400 cables. What should
> the
> > center conductor's resistance read end to end? ~58 Ohms, right? My actual
> > reading bounces all over the place no matter how stable I am in trying to
> > read it. Strange. Also, there doesn't seem to be a short between the
> center
> > conductor and the plug itself when I check it with a multimeter so I'm
> > guessing the plugs were installed correctly.
> >
> > Things I have left to try is just buy a pre-made 12' RG-58 cable from
> radio
> > shack and try it instead of the RG-400 cables. Also, I don't have a spare
> > comm antenna but I think RS carries a replacement 800 Mhz scanner antenna
> > with the right BNC connector that I can just temporarily use just to see if
> > makes any difference at all.
> - - - - - - - - - - - - - - - -
> [Barry] - YOU just answered your own question. The RESISTANCE of a COAX when
> disconnected from both ends should read OPEN _ INFINITY between center
> conductor and shield. It should read SHORT_ ZERO between one end shield and the
> other end shield. It should also read SHORT_ ZERO between one end center
> conductor to other end center conductor.
> As for the COAX, RG-400 is 75 ohm impeadance cable it is also a quad shield
> cable a VERY good cable but not suited for our needs. We should be using RG-58
> or RG-58A/U. It works for us very well. Oh, notice I used the term
> IMPEDANCE. This is an AC resistance and is NOT measured with an OHM Meter.
> Concerning the RG-800 .... I am not familiar with it. RG-58 is what you need
> to use.
Lucky: RG-800? Why did you bring that up? Also, I think RG-400 is RF the same
as RG-58 but better shielded as you point out and it should be superior to RG-58
if cable flexibility isn't an issue. It should NOT be the problem BUT I
threw out using RS pre-made RG-58 just to rule out some manufactering/fabrication
of the pre-made RG-400 cables.
Thanks for the ideas and feedback,
Lucky
> As for the Radio Shack (Real $hit) pre-made COAX stay away from it. I have
> seen so many problems in their assembly, wrong coax, poor connections and
> CRIMPS! You do not want a crimped coax.
>
> NO self-respecting RF Man will accept a CRIMPED coax.
>
>
>
> Barry
> "Chop'd Liver"
>
>
>
>
>
>
>
>
>
>
>
>
<html><body>
<DIV>My answers and corrections to your wrong guesses/assumptions below:</DIV>
<DIV> </DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px
solid">
<P>-------------- Original message -------------- <BR>From: FLYaDIVE@aol.com <BR><BR>>
--> AeroElectric-List message posted by: FLYaDIVE@aol.com <BR>>
<BR>> In a message dated 7/15/06 10:05:43 PM Eastern Daylight Time, <BR>>
luckymacy@comcast.net writes: <BR>> ==========================================
<BR>> Dear UN-Lucky: <BR>> <BR>> Reading your post you seem
to have answered your own questions. I have <BR>> inserted my comments within
the body of your post. Please read on ... <BR>> <BR>> <BR>> > I
have two "comm" issues that I haven't been able to debug to completion <BR>>
yet. <BR>> > I'm using an Xcom 760 radio with their pre-made harness.
<BR>> > <BR>> > 1) I still hear my strobes in my headset even when
they are grounded with <BR>> > the radio ground and even when I put power
noise filters on. However, the <BR>> > Radio Shack noise filters reference
on Bob's web site were reported to me <BR>>
to <B
R>> > be no longer carried by them. So I used the only ones I could find
locally <BR>> > which were sold by Pep Boys and the capacitor was 4700 uF
instead of 2200 <BR>> uF <BR>> > like Radio Shack apparently was. <BR>>
- - - - - - - - - - <BR>> [Barry] - Strobe ground and Radio ground?
I'm not sure what you are <BR>> referring to here. Can you elaborate a bit
more? </P>
<P>Lucky: My 2 strobe power supplies are installed at the wing tip and grounded
to the wing spar locally. Moving the grounds to back in the area
where the rest of my electronics were grounded including the XCOM radio didn't
have any affect.</P>
<P>Also, disconnecting one strobe's power supply at a time didn't show that just
one was the culprit. They were both equal contributors. Installing
the audio noise filters out at the wing tips on the 14vdc input line just prior
to the strobe power supply had no affect. Installing one of those audio
noise filters (a plastic box with an inductor and a capacitor) on the 14vdc input
line to the xcom radio itself also had no affect. </P>
<P>BTW, after I originally bought and installed the Xcom radio, they revised their
drawing and FAQ section to REQUIRE owners install a 22,000 uF cap betwee the
xcom and it's power source near the radio. I didn't do that. Couldn't
locally find such cap. </P>
<P><BR>> BUT, if you are talking about using a SHIELDED wire as your ground
... The <BR>> shield should be grounded ONLY at the STROBE and you should use
two conductor <BR>> and a shield wire. <BR>> As for the value of the
capacitor, in 99.9% of the noise cases concerning a <BR>> DC circuit [our planes]
the bigger the value the better. I really doubt if the <BR>> filter
was designed ONLY for a specific frequency <BR>> ------------------------------------------------------------------------------
</P>
<P>Lucky: I used Van's pre-made wiring kit but I don't recall if the wiring
to the strobes was shielded or not. I'll check on that today to see if
I or Van's made a mistake because there is NO evidence shielded wiring
was used for the strobe power supply. It's been a long time since I hooked
that up originally and haven't looked at that angle yet so details are very
fuzzy. The noise filter was marketed to address noise introduced into radios
when the car's engine RPM is increased. But pulling its case open revealed
it's just the same 3 wire setup that Radio Shack was selling for while
but with a different cap rating.</P>
<P> </P>
<P><BR>> ------------- <BR>> > <BR>> > More specifically, the strobe
noise is relatively faint until I select the <BR>> > Push to Talk button.
Then it gets pretty loud. Some feedback going on <BR>> there. <BR>>
> Looking for ideas from this list. <BR>> - - - - - - - - - - - <BR>>
[Barry] Yup, sure sounds like the Ground for the PTT is the same Ground for
<BR>> the Strobe. Here is where a problem may exist. Reading from either
side of <BR>> the PTT to ground should NOT show continuity. This is a general
statement, each <BR>> radio may be different but you would want to check
this out and make sure the <BR>> PTT runs all the way back to the radio and
NOT to A/C ground. <BR>> -----------------------------------------------------------------------------
</P>
<P>Lucky: I'll check it out today. The original PTT switch came pre-wired
with the radio harness but I cut it off to use a different switch already
installed in my grip but just mirrored the pre-made setup.</P>
<P><BR>> > <BR>> > Should the capacitor specs have made a big difference
on the effectiveness <BR>> > overall of the noise filter? It made
no measurable difference regardless <BR>> of <BR>> > whether I installed
it just before the radio or out at the strobe's power <BR>> > supply
just before the AC +14v entered the power supply. I even reversed <BR>> >
direction of the filter and it didn't matter one iota. Really bummed out <BR>>
> about this turn of events since I thought they'd at least have made
some <BR>> > observable difference based upon stuff in the archives. <BR>>
- - - - - - - - - - <BR>> [Barry] - QUESTIONS: <BR>> How many leads
does the filter have? <BR>> What are they labeled? <BR>> Most filters
will have three of four leads. They may be: (4 lead) Pos & Neg <BR>>
INPUT with Pos & Neg OUTPUT. Or, (3 lead) Pos & Neg INPUT with a Pos OUTPUT
<BR>> {common Ground/Neg}. <BR>> The filt
er sho
uld go ON the device that is making the noise ... STROBE. <BR>> But, you have
to go back and check how you hooked up the GROUNDS. <BR>> I'm betting that:
<BR>> 1 - The filter is not right next to the strobe. <BR>> 2 - The power
leads are not shielded. <BR>> 3 - The ground goes all the way back to
the area of the radios. <BR>> ------------------------------------------------------------------------------
</P>
<P>Lucky: Filter has 3 leads. A postive IN, a Positive OUT and a ground
lead coming from the same physical side off the box as the Positive OUT lead.
It was installed literally adjacent to the strobes power supply's input
voltage matching the filter's instructions with no affect and I reversed
the filters Positive In/Out leads just for grins but again it made zero difference.
I put in on just before the radio too and it also made no difference.
The directions that came with it were assuming you were going to install
it between a car radio and it's input voltage to clean up the input voltage.
Not somewhere else near the actual source of "noise".</P>
<P><BR>> - <BR>> > 2) The second overall problem is that the radio still
is reported to me <BR>> by <BR>> > other pilots as weak when I get
much beyond a couple of miles and breaks up <BR>> > in the pattern a lot.
I'm guessing it's because I can't put out enough <BR>> > consistent power
to break their squelch consistently. When on the actual <BR>> > ground
taxiing around, if there's a crown or "hill" between me and another <BR>>
> airplane on the ground forget it. They can't hear me or vice a versa.
<BR>> > <BR>> > When I check my radio with a handheld on the ground
I seem to be just fine <BR>> > for the relatively close distances I've
tried even when the plane is inside <BR>> > an open hangar and come in
just as loud on the hand held as anyone else is. <BR>> <BR>> > It also
doesn't matter whether or not the strobes are powered on or not as <BR>>
> far as whether or not the range/strength improve
s. ie,
even with them off <BR>> > the lack of range doesn't improve. <BR>> >
<BR>> > I swapped the cable between the radio and the antenna and it
made no <BR>> > difference. I bought my antenna from Van's but didn't do
any kind of post <BR>> > install test besides checking it out with my
comm radio and a hand held and <BR>> > it seemed fine at the time... <BR>>
- - - - - - - - - - - - <BR>> [Barry] - What kind of antenna are you
using and where is it mounted? <BR>> ------------------------------------------------------------------------------
</P>
<P>It's one of the bent which antennas that Van's sells. Don't remember the
brand. Will look it over again today.</P>
<P><BR>> ------- <BR>> > Instead of using RG-58 I bought two pre-made
RG-400 cables. What should <BR>> the <BR>> > center conductor's resistance
read end to end? ~58 Ohms, right? My actual <BR>> > reading bounces
all over the place no matter how stable I am in trying to <BR>> > read
it. Strange. Also, there doesn't seem to be a short between the <BR>> center
<BR>> > conductor and the plug itself when I check it with a multimeter
so I'm <BR>> > guessing the plugs were installed correctly. <BR>>
> <BR>> > Things I have left to try is just buy a pre-made 12' RG-58
cable from <BR>> radio <BR>> > shack and try it instead of the RG-400
cables. Also, I don't have a spare <BR>> > comm antenna but I think RS
carries a replacement 800 Mhz scanner antenna <BR>> > with the right BNC
connector that I can just temporarily use just to see if <BR>> > makes
any difference at all. <BR>> - - - - - - - - - - -
- - -
- - <BR>> [Barry] - YOU just answered your own question. The RESISTANCE of
a COAX when <BR>> disconnected from both ends should read OPEN _ INFINITY between
center <BR>> conductor and shield. It should read SHORT_ ZERO between
one end shield and the <BR>> other end shield. It should also read SHORT_
ZERO between one end center <BR>> conductor to other end center conductor.
<BR>> As for the COAX, RG-400 is 75 ohm impeadance cable it is also a quad
shield <BR>> cable a VERY good cable but not suited for our needs. We should
be using RG-58 <BR>> or RG-58A/U. It works for us very well. Oh, notice
I used the term <BR>> IMPEDANCE. This is an AC resistance and is NOT measured
with an OHM Meter. <BR>> Concerning the RG-800 .... I am not familiar with
it. RG-58 is what you need <BR>> to use. </P>
<P> </P>
<P>Lucky: RG-800? Why did you bring that up? Also, I think RG-400
is RF the same as RG-58 but better shielded as you point out and it should
be superior to RG-58 if cable flexibility isn't an issue. It should NOT
be the problem BUT I threw out using RS pre-made RG-58 just to rule out some
manufactering/fabrication of the pre-made RG-400 cables.</P>
<P> </P>
<P>Thanks for the ideas and feedback,</P>
<P>Lucky</P>
atroni
Message 3
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Subject: | Re: Help needed: continued strobe noise & weak |
--> AeroElectric-List message posted by: Ken <klehman@albedo.net>
Hi Barry
My references indicate that RG-400 and RG-58 are both 50 ohm coax and
that RG-400 is lower loss and preferable ??
Ken
snip
>As for the COAX, RG-400 is 75 ohm impeadance cable it is also a quad shield
>cable a VERY good cable but not suited for our needs. We should be using RG-58
>or RG-58A/U. It works for us very well. Oh, notice I used the term
>IMPEDANCE. This is an AC resistance and is NOT measured with an OHM Meter.
>Concerning the RG-800 .... I am not familiar with it. RG-58 is what you need
>to use.
>As for the Radio Shack (Real $hit) pre-made COAX stay away from it. I have
>seen so many problems in their assembly, wrong coax, poor connections and
>CRIMPS! You do not want a crimped coax.
>
>NO self-respecting RF Man will accept a CRIMPED coax.
>
>
>Barry
>"Chop'd Liver"
>
>
Message 4
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Subject: | Re: Help needed: continued strobe noise & weak radio |
-------------- Original message --------------
In a message dated 7/15/2006 10:05:43 P.M. Eastern Daylight Time, luckymacy@comcast.net
writes:
Instead of using RG-58 I bought two pre-made RG-400 cables. What should the center
conductor's resistance read end to end? ~58 Ohms, right? My actual reading
bounces all over the place no matter how stable I am in trying to read it.
Strange. Also, there doesn't seem to be a short between the center conductor
and the plug itself when I check it with a multimeter so I'm guessing the plugs
were installed correctly.
No, with a DC meter the cable should read very low resistance from end to end on
the center conductor. You should measure an open from center conductor to shield.
And you should measure a short from end to end on the outer shield of
the fittings. It sounds like you may have a bad (loose) connection. The 50 ohms
refers to the high frequency characteristic impedance of the cable. That
is the ratio of voltage to current in the cable is (or should be) 50 ohms while
it is conducting RF.
Lucky: Yep, what was I thinking when I wrote that. The resistance from tip to
tip is basically zero and both sides off the cable show open between the center
conductor's tip and the shield.
Also, I mention using this cable not because it should work well but to use ANY
antenna temporarily that's isolated from the airframe to help in figuring out
of the current one is part of the problem.
Things I have left to try is just buy a pre-made 12' RG-58 cable from radio shack
and try it instead of the RG-400 cables. Also, I don't have a spare comm antenna
but I think RS carries a replacement 800 Mhz scanner antenna with the right
BNC connector that I can just temporarily use just to see if makes any difference
at all.
Forget trying to use the 800 MHz antenna on the VHF Aircraft Band -- not a good
idea at all.
Any ideas from the list?
I recommend finding a ham operator with an MFJ-259B or similar type instrument
that will measure the SWR of your antenna system. That is, check out your feedline
and antenna. Try to determine if the antenna is OK then check antenna and
feedline together, etc.
Make sure the antenna is grounded to the aircraft skin by measuring from the coax
fitting with the coax disconnected to the skin with a DC ohmmeter. You should
measure a short.
Hope this helps,
Dan Hopper
K9WEK
RV-7A
<html><body>
<DIV> </DIV>
<DIV> </DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px
solid">-------------- Original message -------------- <BR>From: Hopperdhh@aol.com
<BR>
<META content="MSHTML 6.00.2900.2912" name=GENERATOR><FONT id=role_document face=Arial
color=#000000 size=2>
<DIV>In a message dated 7/15/2006 10:05:43 P.M. Eastern Daylight Time, luckymacy@comcast.net
writes:</DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>Instead
of using RG-58 I bought two pre-made RG-400 cables. What should
the center conductor's resistance read end to end? ~58 Ohms, right?
My actual reading bounces all over the place no matter how stable I am in trying
to read it. Strange. Also, there doesn't seem to be a short between
the center conductor and the plug itself when I check it with a multimeter
so I'm guessing the plugs were installed correctly.<BR></FONT></BLOCKQUOTE>
<DIV>No, with a DC meter the cable should read very low resistance from end to
end on the center conductor. You should measure an open from center conductor
to shield. And you should measure a short from end to end on the outer
shield of the fittings. It sounds like you may have a bad (loose) connection.
The 50 ohms refers to the high frequency characteristic impedance
of the cable. That is the ratio of voltage to current in the cable
is (or should be) 50 ohms while it is conducting RF.</DIV>
<DIV><BR> </DIV>
<DIV>Lucky: Yep, what was I thinking when I wrote that. The resistance
from tip to tip is basically zero and both sides off the cable show open between
the center conductor's tip and the shield.</DIV>
<DIV> </DIV>
<DIV>Also, I mention using this cable not because it should work well but to use
ANY antenna temporarily that's isolated from the airframe to help in figuring
out of the current one is part of the problem.</DIV>
<DIV> </DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2><BR>Things
I have left to try is just buy a pre-made 12' RG-58 cable from
radio shack and try it instead of the RG-400 cables. Also, I don't have
a spare comm antenna but I think RS carries a replacement 800 Mhz scanner antenna
with the right BNC connector that I can just temporarily use just to see if
makes any difference at all. <BR></FONT></BLOCKQUOTE>
<DIV>Forget trying to use the 800 MHz antenna on the VHF Aircraft Band -- not a
good idea at all.</DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2><BR>Any
ideas from the list?<BR><BR><BR></FONT></BLOCKQUOTE>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>I recommend finding a ham operator with an MFJ-259B or similar type instrument
that will measure the SWR of your antenna system. That is, check out
your feedline and antenna. Try to determine if the antenna is OK then
check antenna and feedline together, etc.</DIV>
<DIV> </DIV>
<DIV>Make sure the antenna is grounded to the aircraft skin by measuring from the
coax fitting with the coax disconnected to the skin with a DC ohmmeter.
You should measure a short.</DIV>
<DIV> </DIV>
<DIV>Hope this helps,</DIV>
<DIV> </DIV>
<DIV>Dan Hopper</DIV>
<DIV>K9WEK</DIV>
<DIV>RV-7A</DIV>
<DIV> </DIV></FONT></BLOCKQUOTE></body></html>
Message 5
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|
Subject: | Landing lights & relays |
What is your opinion of using mechanical relays to implement wig-wag flashing of
landing lights?
I would like to use a rotary switch with the following pattern: off, wig-wag, landing,
taxi (4 positions). Otherwise I would need to use 3 toggle switches and
a complicated switch operation. Using transistors would lower the voltage at
the light by about 1.5 volts. To confuse the issue further, I have wingtip landing
and taxi lights (1 landing and 1 taxi on each wing) 4 lights total. Using
relays would solve my problems, but I don't know the longevity of the relay.
What are your thoughts?
Thanks,
Tom Costanza
RV-7A Fuselage
<html><body>
<DIV><FONT size=2>
<P>What is your opinion of using mechanical relays to implement wig-wag flashing
of landing lights? </P>
<P>I would like to use a rotary switch with the following pattern: off,
wig-wag, landing, taxi (4 positions). Otherwise I would need to use 3 toggle
switches and a complicated switch operation. Using transistors would lower the
voltage at the light by about 1.5 volts. To confuse the issue further, I have
wingtip landing and taxi lights (1 landing and 1 taxi on each wing) 4 lights
total. Using relays would solve my problems, but I don't know the longevity
of the relay. </P>
<P>What are your thoughts?</P>
<P>Thanks,</P>
<P>Tom Costanza</P>
<P>RV-7A Fuselage</P></FONT></DIV></body></html>
Message 6
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|
Subject: | Hall effect amp meter telling the truth? |
--> AeroElectric-List message posted by: Duane Wilson <aaa@pacifier.com>
I have a Hall effect current sensor hooked up to my GRT EIS-4000. I
have set the parameters in the EIS as stated on the instillation sheet
for the Hall effect sensor.
When I turn on my 2 GRT Horizon 1 displays, my Val avionics VOR, Garmin
300XL, transponder (standby) and panel lights I get a reading of about
.6 on the EIS.
This seems low to me. How can I verify the current draw. I don't have
an amp meter.
Duane Wilson
Message 7
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Subject: | VM1000 light system failure |
--> AeroElectric-List message posted by: "Ralph E. Capen" <recapen@earthlink.net>
Fellow listers,
Anyone out there experience a failure mode with their VM1000 internal
lighting system? The lights worked up until a few days ago...I'm trying to
remember if I have done anything to the lighting system that might cause the
failure mode sooooo........
Here's the troubleshooting that I have already done:
Pin 20 has 13.3 VDC
Pin 21 has between 4.1 VDC and 10.8 VDC depending on the dimmer setting
Pin 22 has continuity to ground
These three are 'as designed' in my opinion - so the proper stuff is at
least getting to the DPU.
Is there something that I can check on the cable between the DPU and the
display?
I've sent a note to Vision Microsystems - I'll post their response.........
Ralph Capen
Message 8
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|
I noticed the old figure Z-7 for the Rotax 912 installation has been replaced
by figure Z-16. I've had my Rans S7 flying for over 200 hours and was wondering
if I should make the changes to my system to update it to the new schematic?
Was there a problem with the old figure Z-7?
Mike
---------------------------------
See the all-new, redesigned Yahoo.com. Check it out.
Message 9
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|
Subject: | Re: Help needed: continued strobe noise & weak radio |
--> AeroElectric-List message posted by: Brian Lloyd <brian-yak@lloyd.com>
On Jul 15, 2006, at 9:54 PM, lucky wrote:
> --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky)
>
> I have two "comm" issues that I haven't been able to debug to
> completion yet. I'm using an Xcom 760 radio with their pre-made
> harness.
>
> 1) I still hear my strobes in my headset even when they are
> grounded with the radio ground and even when I put power noise
> filters on. However, the Radio Shack noise filters reference on
> Bob's web site were reported to me to be no longer carried by
> them. So I used the only ones I could find locally which were sold
> by Pep Boys and the capacitor was 4700 uF instead of 2200 uF like
> Radio Shack apparently was.
Make sure your mic and headphone jacks are insulated from the
airframe. Use fiber insulating washers between the jack and the panel.
The 4700 uF cap is fine as it will have about twice the filtering of
a 2200 uF cap. OTOH, if all your filter is is a capacitor, it will
have almost no effect. You also need a choke in series with the power
lead like this:
fuseblock ---------[choke]----+-------->[radio]
|
[capacitor]
|
v
ground
Brian Lloyd 361 Catterline Way
brian-yak AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
Message 10
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|
Subject: | Re: Landing lights & relays |
Tom,
One way to look at this is that if landing/taxi lights (nor wig/wag) are
not required for night flight, so what does it matter if the relay
fails? One landing without the benefit of them? I would just get a
quality relay and let the longevity concern take care of itself - don't
plan to do much night flying anyway.
Do you preflight check all the lights and wig/wag function? (This is
rhetorical. If not, then how do you not know whether a light has burned
out, a more likely event that losing a relay, I think. I would check
light function only if I thought I would have the potential to use them
during a flight. Obviously, if you use wig-wag as a safety feature
during normal flights, one would check proper operation before takeoff.)
Regards,
Doug Windhorn
----- Original Message -----
From: tomcostanza@comcast.net
To: aeroelectric-list@matronics.com
Sent: Sunday, 16 July, 2006 6:53
Subject: AeroElectric-List: Landing lights & relays
What is your opinion of using mechanical relays to implement wig-wag
flashing of landing lights?
I would like to use a rotary switch with the following pattern: off,
wig-wag, landing, taxi (4 positions). Otherwise I would need to use 3
toggle switches and a complicated switch operation. Using transistors
would lower the voltage at the light by about 1.5 volts. To confuse the
issue further, I have wingtip landing and taxi lights (1 landing and 1
taxi on each wing) 4 lights total. Using relays would solve my problems,
but I don't know the longevity of the relay.
What are your thoughts?
Thanks,
Tom Costanza
RV-7A Fuselage
Message 11
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|
Subject: | Re: Landing lights & relays |
--> AeroElectric-List message posted by: Ken <klehman@albedo.net>
Not sure how many lights you have Tom. I have a landing light and a taxi
light in both wingtips. Four lamps total. One toggle switch turns on
both landing lights. Another toggle switch turns on both taxi lights. A
third toggle switch selects whether the two taxi lights stay on steady
or wig wag when the taxi lights are on. No relays, diodes, or
transistors. Common cheap toggle switches and an off the shelf cheap
automotive mechancal flasher (OK I guess there is a relay inside the
flasher ;) Seemed pretty simple to me. For daytime operation all I
ever touch is the taxi light switch.
Ken
tomcostanza@comcast.net wrote:
> What is your opinion of using mechanical relays to implement wig-wag
> flashing of landing lights?
>
> I would like to use a rotary switch with the following pattern: off,
> wig-wag, landing, taxi (4 positions). Otherwise I would need to use 3
> toggle switches and a complicated switch operation. Using transistors
> would lower the voltage at the light by about 1.5 volts. To confuse
> the issue further, I have wingtip landing and taxi lights (1 landing
> and 1 taxi on each wing) 4 lights total. Using relays would solve my
> problems, but I don't know the longevity of the relay.
>
> What are your thoughts?
>
> Thanks,
>
> Tom Costanza
>
> RV-7A Fuselage
>
Message 12
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|
Subject: | Re: Hall effect amp meter telling the truth? |
--> AeroElectric-List message posted by: Ken <klehman@albedo.net>
Hi Duane
The stuff you mentioned doesn't draw much so it might be OK but I do
seem to recall having to tweak the settings to get mine to read
accurately. Best way is a cheap digital meter as I've seen ones that
will read 10 amps for under $10. You almost have to have something like
that in your bag of tools anyway. For a gross check within 10 or 20%
how about connecting up something with a known resistance or current
draw like perhaps a landing light?
Ken.
Duane Wilson wrote:
> --> AeroElectric-List message posted by: Duane Wilson <aaa@pacifier.com>
>
> I have a Hall effect current sensor hooked up to my GRT EIS-4000. I
> have set the parameters in the EIS as stated on the instillation sheet
> for the Hall effect sensor.
>
> When I turn on my 2 GRT Horizon 1 displays, my Val avionics VOR,
> Garmin 300XL, transponder (standby) and panel lights I get a reading
> of about .6 on the EIS.
>
> This seems low to me. How can I verify the current draw. I don't
> have an amp meter.
>
> Duane Wilson
Message 13
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|
Subject: | Re: VM1000 light system failure |
--> AeroElectric-List message posted by: "Harry Manvel" <hmanvel@manvel.com>
I had one that failed and had to send it in to Vision and get the lighting
repaired. It still would light, but real dim. Not sure what caused it but
it's fixed now.
Harry Manvel
Defiant N2HM
PTK / Pontiac, MI
----- Original Message -----
Sent: Sunday, July 16, 2006 10:08 AM
> --> AeroElectric-List message posted by: "Ralph E. Capen"
> <recapen@earthlink.net>
>
> Fellow listers,
>
> Anyone out there experience a failure mode with their VM1000 internal
> lighting system? The lights worked up until a few days ago...I'm trying
> to remember if I have done anything to the lighting system that might
> cause the failure mode sooooo........
>
> Here's the troubleshooting that I have already done:
>
> Pin 20 has 13.3 VDC
> Pin 21 has between 4.1 VDC and 10.8 VDC depending on the dimmer setting
> Pin 22 has continuity to ground
>
> These three are 'as designed' in my opinion - so the proper stuff is at
> least getting to the DPU.
> Is there something that I can check on the cable between the DPU and the
> display?
>
> I've sent a note to Vision Microsystems - I'll post their
> response.........
>
> Ralph Capen
>
>
> http://www.matronics.com/Navigator?AeroElectric-List
> http://wiki.matronics.com
>
>
>
Message 14
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|
Subject: | Re: Hall effect amp meter telling the truth? |
Duane,
I was in at our new Harbor Freight store and they had neat little digital
meters on sale for $2.99. Had a 10 amp scale, too. I don't need another
meter, but I almost bought a couple anyway.
Dan
do not archive
In a message dated 7/16/2006 3:29:13 P.M. Eastern Daylight Time,
klehman@albedo.net writes:
--> AeroElectric-List message posted by: Ken <klehman@albedo.net>
Hi Duane
The stuff you mentioned doesn't draw much so it might be OK but I do
seem to recall having to tweak the settings to get mine to read
accurately. Best way is a cheap digital meter as I've seen ones that
will read 10 amps for under $10. You almost have to have something like
that in your bag of tools anyway. For a gross check within 10 or 20%
how about connecting up something with a known resistance or current
draw like perhaps a landing light?
Ken.
Duane Wilson wrote:
> --> AeroElectric-List message posted by: Duane Wilson <aaa@pacifier.com>
>
> I have a Hall effect current sensor hooked up to my GRT EIS-4000. I
> have set the parameters in the EIS as stated on the instillation sheet
> for the Hall effect sensor.
>
> When I turn on my 2 GRT Horizon 1 displays, my Val avionics VOR,
> Garmin 300XL, transponder (standby) and panel lights I get a reading
> of about .6 on the EIS.
>
> This seems low to me. How can I verify the current draw. I don't
> have an amp meter.
>
> Duane Wilson
Message 15
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|
Subject: | Re: Grounding lugs |
My mistake, They are steel not brass...
On 7/16/06, John McMahon <blackoaks@gmail.com> wrote:
>
> Ok, got the transponder info, now...
>
> I am still wondering if I need to change out the 1/4" brass thru firewall
> studs put in by Lancair. I am using #2 welding cable for the batteries. If
> I've done the calculations correctly the diameter of AWG2 is .27", just
> slightly more than 1/4". Would that .02 require going to 5/16" studs?
>
> Thanks to all who jumped in on the transponder part of the question.
> >
> >
> >
> > > > Second question regards the transmission of the transponder
> > > > signal. Does the signal rediate from the shaft and the ball or
> >
> >
>
>
> --
> John McMahon
> Lancair Super ES, N9637M
>
--
John McMahon
Lancair Super ES, N9637M
Message 16
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|
Subject: | Re: Grounding lugs |
Ok, got the transponder info, now...
I am still wondering if I need to change out the 1/4" brass thru firewall
studs put in by Lancair. I am using #2 welding cable for the batteries. If
I've done the calculations correctly the diameter of AWG2 is .27", just
slightly more than 1/4". Would that .02 require going to 5/16" studs?
Thanks to all who jumped in on the transponder part of the question.
>
>
> > > Second question regards the transmission of the transponder
> > > signal. Does the signal rediate from the shaft and the ball or
>
>
--
John McMahon
Lancair Super ES, N9637M
Message 17
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Subject: | Re: Grounding lugs |
In a message dated 7/16/2006 5:18:40 P.M. Eastern Daylight Time,
blackoaks@gmail.com writes:
Ok, got the transponder info, now...
I am still wondering if I need to change out the 1/4" brass thru firewall
studs put in by Lancair. I am using #2 welding cable for the batteries. If
I've done the calculations correctly the diameter of AWG2 is .27", just
slightly more than 1/4". Would that .02 require going to 5/16" studs?
Thanks to all who jumped in on the transponder part of the question.
John,
No, It doesn't make any difference. Even steel is OK. In fact brass is not
a very good conductor, believe it or not. It is much closer to steel than
to copper. There is not that much resistance in the short length we are
talking about. The main thing is a clean connection that won't corrode, and that
is mechanically strong enough that it is reliable.
Dan Hopper
RV-7A
Message 18
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|
Subject: | Re: Grounding lugs |
--> AeroElectric-List message posted by: Brian Lloyd <brian-yak@lloyd.com>
On Jul 16, 2006, at 5:10 PM, John McMahon wrote:
> Ok, got the transponder info, now...
>
> I am still wondering if I need to change out the 1/4" brass thru
> firewall studs put in by Lancair. I am using #2 welding cable for
> the batteries. If I've done the calculations correctly the
> diameter of AWG2 is .27", just slightly more than 1/4". Would
> that .02 require going to 5/16" studs?
No. The existing 1/4" stud will work just fine. There is likely more
loss in the connection itself than in the resistance of the stud.
Brian Lloyd 361 Catterline Way
brian-yak AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
Message 19
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|
Subject: | Re: VM1000 light system failure |
--> AeroElectric-List message posted by: "Ralph E. Capen" <recapen@earthlink.net>
Was it the display that failed or the DPU?
Thanks,
Ralph
----- Original Message -----
Sent: Sunday, July 16, 2006 3:39 PM
> --> AeroElectric-List message posted by: "Harry Manvel"
> <hmanvel@manvel.com>
>
> I had one that failed and had to send it in to Vision and get the lighting
> repaired. It still would light, but real dim. Not sure what caused it but
> it's fixed now.
> Harry Manvel
> Defiant N2HM
> PTK / Pontiac, MI
>
> ----- Original Message -----
> Sent: Sunday, July 16, 2006 10:08 AM
>
>
>> --> AeroElectric-List message posted by: "Ralph E. Capen"
>> <recapen@earthlink.net>
>>
>> Fellow listers,
>>
>> Anyone out there experience a failure mode with their VM1000 internal
>> lighting system? The lights worked up until a few days ago...I'm trying
>> to remember if I have done anything to the lighting system that might
>> cause the failure mode sooooo........
>>
>> Here's the troubleshooting that I have already done:
>>
>> Pin 20 has 13.3 VDC
>> Pin 21 has between 4.1 VDC and 10.8 VDC depending on the dimmer setting
>> Pin 22 has continuity to ground
>>
>> These three are 'as designed' in my opinion - so the proper stuff is at
>> least getting to the DPU.
>> Is there something that I can check on the cable between the DPU and the
>> display?
>>
>> I've sent a note to Vision Microsystems - I'll post their
>> response.........
>>
>> Ralph Capen
>>
>>
>>
>> http://www.matronics.com/Navigator?AeroElectric-List
>> http://wiki.matronics.com
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
> http://www.matronics.com/Navigator?AeroElectric-List
> http://wiki.matronics.com
>
>
>
Message 20
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Subject: | Re: Landing lights & relays |
Doug,
That's reasonable as long as the relay doesn't go South every couple months.I don't
spend all my time replacing relays. The other concern was RFI.I also don't
want to listen to the lights flashing or have them interferewith navigation.
Thanks for the reply. If you have any further thoughts, I would be very interested.
Regards,Tom Costanza
Tom,
One way to look at this is that if landing/taxi lights (nor wig/wag) are
not required for night flight, so what does it matter if the relay
fails? One landing without the benefit of them? I would just get a
quality relay and let the longevity concern take care of itself - don't
plan to do much night flying anyway.
Do you preflight check all the lights and wig/wag function? (This is
rhetorical. If not, then how do you not know whether a light has burned
out, a more likely event that losing a relay, I think. I would check
light function only if I thought I would have the potential to use them
during a flight. Obviously, if you use wig-wag as a safety feature
during normal flights, one would check proper operation before takeoff.)
Regards,
Doug Windhorn
----- Original Message -----
From: tomcostanza@comcast.net
To: aeroelectric-list@matronics.com
Sent: Sunday, 16 July, 2006 6:53
Subject: Landing lights & relays
What is your opinion of using mechanical relays to implement wig-wag
flashing of landing lights?
I would like to use a rotary switch with the following pattern: off,
wig-wag, landing, taxi (4 positions). Otherwise I would need to use 3
toggle switches and a complicated switch operation. Using transistors
would lower the voltage at the light by about 1.5 volts. To confuse the
issue further, I have wingtip landing and taxi lights (1 landing and 1
taxi on each wing) 4 lights total. Using relays would solve my problems,
but I don't know the longevity of the relay.
What are your thoughts?
Thanks,
Tom Costanza
RV-7A Fuselage
<html><body>
<DIV><B><PRE>Doug,</PRE><PRE>That's reasonable as long as the relay doesn't go
South every couple months.<BR>I don't spend all my time replacing relays. The
other concern was RFI.<BR>I also don't want to listen to the lights flashing
or have them interfere<BR>with navigation.</PRE><PRE>Thanks for the reply. If
you have any further thoughts, I would be very interested.</PRE><PRE>Regards,<BR>Tom
Costanza</PRE><PRE> </PRE><PRE>Tom,
One way to look at this is that if landing/taxi lights (nor wig/wag) are
not required for night flight, so what does it matter if the relay
fails? One landing without the benefit of them? I would just get a
quality relay and let the longevity concern take care of itself - don't
plan to do much night flying anyway.
Do you preflight check all the lights and wig/wag function? (This is
rhetorical. If not, then how do you not know whether a light has burned
out, a more likely event that losing a relay, I think. I would check
light function only if I thought I would have the potential to use them
during a flight. Obviously, if you use wig-wag as a safety feature
during normal flights, one would check proper operation before takeoff.)
Regards,
Doug Windhorn
----- Original Message -----
From: <A href="mailto:tomcostanza@comcast.net?subject=Re:%20Landing%20lights%20&%20relays&replyto=004001c6a8f6$6e628790$6602a8c0@desktop">tomcostanza@comcast.net</A>
To: <A href="mailto:aeroelectric-list@matronics.com?subject=Re:%20Landing%20lights%20&%20relays&replyto=004001c6a8f6$6e628790$6602a8c0@desktop">aeroelectric-list@matronics.com</A>
Sent: Sunday, 16 July, 2006 6:53
Subject: Landing lights & relays
What is your opinion of using mechanical relays to implement wig-wag
flashing of landing lights?
I would like to use a rotary switch with the following pattern: off,
wig-wag, landing, taxi (4 positions). Otherwise I would need to use 3
toggle switches and a complicated switch operation. Using transistors
would lower the voltage at the light by about 1.5 volts. To confuse the
issue further, I have wingtip landing and taxi lights (1 landing and 1
taxi on each wing) 4 lights total. Using relays would solve my problems,
but I don't know the longevity of the relay.
What are your thoughts?
Thanks,
Tom Costanza
RV-7A Fuselage
</PRE><PRE></PRE></B>
<P><!-- body="end" --></P></DIV></body></html>
Message 21
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--> AeroElectric-List message posted by: "Alex Balic" <alex157@pwhome.com>
Anyone have any experience/ comments/ problems with the Blue Sea BatteryLink
ACR unit? www.bluesea.com Seems to be a good device to allow linking
up/charging of 2 batteries. But I am having trouble figuring out how it
could be included into the schematic utilizing the separate battery
contactors- I am thinking it might simply replace the cross feed contactor?
Anyone using one?
Message 22
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Subject: | Re: Landing lights & relays |
Hi Ken,
That's the configuration I'll have. I started with that approach, but wanted to
keep the switch count to a minimum. I guess you pay your money and take your
choice. I ordered some spare bulbs and think I'll do an experiment and see
what happens.
Thanks for the reply.
Regards,
Tom Costanza
Not sure how many lights you have Tom. I have a landing light and a taxi
light in both wingtips. Four lamps total. One toggle switch turns on
both landing lights. Another toggle switch turns on both taxi lights. A
third toggle switch selects whether the two taxi lights stay on steady
or wig wag when the taxi lights are on. No relays, diodes, or
transistors. Common cheap toggle switches and an off the shelf cheap
automotive mechancal flasher (OK I guess there is a relay inside the
flasher ;) Seemed pretty simple to me. For daytime operation all I
ever touch is the taxi light switch.
Ken
tomcostanza@comcast.net wrote:
> What is your opinion of using mechanical relays to implement wig-wag
> flashing of landing lights?
>
> I would like to use a rotary switch with the following pattern: off,
> wig-wag, landing, taxi (4 positions). Otherwise I would need to use 3
> toggle switches and a complicated switch operation. Using transistors
> would lower the voltage at the light by about 1.5 volts. To confuse
> the issue further, I have wingtip landing and taxi lights (1 landing
> and 1 taxi on each wing) 4 lights total. Using relays would solve my
> problems, but I don't know the longevity of the relay.
>
> What are your thoughts?
>
> Thanks,
>
> Tom Costanza
>
> RV-7A Fuselage
>
<html><body>
<DIV>Hi Ken,</DIV>
<DIV> </DIV>
<DIV>That's the configuration I'll have. I started with that approach, but
wanted to keep the switch count to a minimum. I guess you pay your money
and take your choice. I ordered some spare bulbs and think I'll do an
experiment and see what happens.</DIV>
<DIV> </DIV>
<DIV>Thanks for the reply.</DIV>
<DIV> </DIV>
<DIV>Regards,</DIV>
<DIV>Tom Costanza</DIV>
<DIV> </DIV>
<DIV>Not sure how many lights you have Tom. I have a landing light and a taxi <BR>light in both wingtips. Four lamps total. One toggle switch turns on <BR>both landing lights. Another toggle switch turns on both taxi lights. A <BR>third toggle switch selects whether the two taxi lights stay on steady <BR>or wig wag when the taxi lights are on. No relays, diodes, or <BR>transistors. Common cheap toggle switches and an off the shelf cheap <BR>automotive mechancal flasher (OK I guess there is a relay inside the <BR>flasher ;) Seemed pretty simple to me. For daytime operation all I <BR>ever touch is the taxi light switch.<BR>Ken<BR><BR><A href="mailto:tomcostanza@comcast.net?subject=Re:%20Landing%20lights%20&%20relays&replyto=44BA83C9.9080404@albedo.net">tomcostanza@comcast.net</A> wrote:<BR><BR>> What is your opinion of using mechanical relays to implement wig-wag <BR>> flashing of landing lights?<BR>><BR>> I would like to use a rotary switch with
the f
ollowing pattern: off, <BR>> wig-wag, landing, taxi (4 positions). Otherwise
I would need to use 3 <BR>> toggle switches and a complicated switch operation.
Using transistors <BR>> would lower the voltage at the light by about
1.5 volts. To confuse <BR>> the issue further, I have wingtip landing and
taxi lights (1 landing <BR>> and 1 taxi on each wing) 4 lights total. Using
relays would solve my <BR>> problems, but I don't know the longevity of the
relay.<BR>><BR>> What are your thoughts?<BR>><BR>> Thanks,<BR>><BR>>
Tom Costanza<BR>><BR>> RV-7A Fuselage<BR>><BR><PRE></PRE>
<P><!-- body="end" --></P></DIV></body></html>
Message 23
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Subject: | Re: BatteryLink ACR |
--> AeroElectric-List message posted by: Brian Lloyd <brian-yak@lloyd.com>
On Jul 16, 2006, at 6:44 PM, Alex Balic wrote:
> --> AeroElectric-List message posted by: "Alex Balic"
> <alex157@pwhome.com>
>
> Anyone have any experience/ comments/ problems with the Blue Sea
> BatteryLink
> ACR unit? www.bluesea.com Seems to be a good device to allow linking
> up/charging of 2 batteries. But I am having trouble figuring out
> how it
> could be included into the schematic utilizing the separate battery
> contactors- I am thinking it might simply replace the cross feed
> contactor?
> Anyone using one?
I have installed them in boats for other people. Basically it
replaces your cross-feed contactor and parallels your batteries when
the bus voltage is above 13.5V indicating that the alternator is on-
line. Once the voltage drops to about 13V it drops out and separates
the batteries.
On a boat it is supposed to allow the charging of the engine-starting
battery and the house battery at the same time but isolating the
engine-starting battery once you are running on battery power to
prevent house loads from running the start battery down and
preventing you from starting your engine.
I prefer the AmplePower battery isolator eliminator. It is a DC/DC
converter that is designed to charge the start battery from the house
bank using a three-phase temperature-compensated charging regimen. It
keeps the start battery on a proper float charge to ensure it is
fully charged. The only problem is that it is limited to 5A draw but
that is not a limitation when just charging the start battery.
Of course, this is for a boat electrical system where it is normal to
run from battery power.
Brian Lloyd 361 Catterline Way
brian-yak AT lloyd DOT com Folsom, CA 95630
+1.916.367.2131 (voice) +1.270.912.0788 (fax)
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
Message 24
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|
Subject: | Re: Help needed: continued strobe noise & weak radio |
I'll take a look at them next time I get out there and I think the mike and headphone
jacks are fitted correctly. If they weren't, wouldn't I have a problem
all the time? In fact, would they work at all? For example, even when using
the radio's internal VOX intercom system wouldn't I get a bad signal and wouldn't
there be a lot of noise from other components whey they are turned on? The
VOX works very well (except that when the strobes are on, yes, you hear them
loud and clear as well). I haven't noticed any other electrical component causing
a problem that's audible and the radio itself hasn't seemed to bother any
other electrical system.
Today I temporarily installed my ELTs antenna on my radio and it didn't help or
seem to hurt from what I could tell on the ground experimenting.
-------------- Original message --------------
> --> AeroElectric-List message posted by: Brian Lloyd
>
>
> On Jul 15, 2006, at 9:54 PM, lucky wrote:
>
> > --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky)
> >
> > I have two "comm" issues that I haven't been able to debug to
> > completion yet. I'm using an Xcom 760 radio with their pre-made
> > harness.
> >
> > 1) I still hear my strobes in my headset even when they are
> > grounded with the radio ground and even when I put power noise
> > filters on. However, the Radio Shack noise filters reference on
> > Bob's web site were reported to me to be no longer carried by
> > them. So I used the only ones I could find locally which were sold
> > by Pep Boys and the capacitor was 4700 uF instead of 2200 uF like
> > Radio Shack apparently was.
>
> Make sure your mic and headphone jacks are insulated from the
> airframe. Use fiber insulating washers between the jack and the panel.
>
> The 4700 uF cap is fine as it will have about twice the filtering of
> a 2200 uF cap. OTOH, if all your filter is is a capacitor, it will
> have almost no effect. You also need a choke in series with the power
> lead like this:
>
> fuseblock ---------[choke]----+-------->[radio]
> [capacitor]
> v
> ground
>
> Brian Lloyd 361 Catterline Way
> brian-yak AT lloyd DOT com Folsom, CA 95630
> +1.916.367.2131 (voice) +1.270.912.0788 (fax)
>
> I fly because it releases my mind from the tyranny of petty things . . .
> Antoine de Saint-Exupry
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
<html><body>
<DIV>I'll take a look at them next time I get out there and I think the mike
and headphone jacks are fitted correctly. If they weren't, wouldn't
I have a problem all the time? In fact, would they work at all? For
example, even when using the radio's internal VOX intercom system wouldn't
I get a bad signal and wouldn't there be a lot of noise from other components
whey they are turned on? The VOX works very well (except that when the
strobes are on, yes, you hear them loud and clear as well). I haven't noticed
any other electrical component causing a problem that's audible and the
radio itself hasn't seemed to bother any other electrical system.</DIV>
<DIV> </DIV>
<DIV>Today I temporarily installed my ELTs antenna on my radio and it didn't help
or seem to hurt from what I could tell on the ground experimenting.</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px
solid">-------------- Original message -------------- <BR>From: Brian Lloyd
<brian-yak@lloyd.com> <BR><BR>> --> AeroElectric-List message posted
by: Brian Lloyd <BRIAN-YAK@LLOYD.COM><BR>> <BR>> <BR>> On Jul 15,
2006, at 9:54 PM, lucky wrote: <BR>> <BR>> > --> AeroElectric-List
message posted by: luckymacy@comcast.net (lucky) <BR>> > <BR>> >
I have two "comm" issues that I haven't been able to debug to <BR>> > completion
yet. I'm using an Xcom 760 radio with their pre-made <BR>> > harness.
<BR>> > <BR>> > 1) I still hear my strobes in my headset even
when they are <BR>> > grounded with the radio ground and even when I
put power noise <BR>> > filters on. However, the Radio Shack noise filters
reference on <BR>> > Bob's web site were reported to me to be no longer
carried by <BR>> > them. So I used the only
ones I
could find locally which were sold <BR>> > by Pep Boys and the capacitor
was 4700 uF instead of 2200 uF like <BR>> > Radio Shack apparently was.
<BR>> <BR>> Make sure your mic and headphone jacks are insulated from the
<BR>> airframe. Use fiber insulating washers between the jack and the panel.
<BR>> <BR>> The 4700 uF cap is fine as it will have about twice the
filtering of <BR>> a 2200 uF cap. OTOH, if all your filter is is a capacitor,
it will <BR>> have almost no effect. You also need a choke in series with
the power <BR>> lead like this: <BR>> <BR>> fuseblock ---------[choke]----+-------->[radio]
<BR>> | <BR>> [capacitor] <BR>> | <BR>>
v <BR>> ground <BR>> <BR>> Brian Lloyd 361 Catterline Way <BR>>
brian-yak AT lloyd DOT com Folsom, CA 95630 <BR>> +1.916.367.2131 (voice)
+1.270.912.0788 (fax) <BR>> <BR>> I fly because it releases my mind from
the tyranny of petty things . . . <BR>> Antoine
de Sa
http:
Message 25
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Subject: | Re: Help needed: continued strobe noise & weak radio |
Lucky,
Did you check to see if the antenna ground is grounded to the skin?
Dan
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Subject: | braided bonding straps |
I know I can order these to a pre-set length, but I've removed probably 2.5'
of braid shield from some RG-58 and wondering what all I can do with it. I
know I can use attach a connector and use it as a circuit ground,
but I'm wondering if it will also work for some of these static charge
installations: aileron to wing, flap to wing, elevator to HS; and some of
the heftier installations: engine to firewall stud, battery negative post to
airframe, etc.
Rob Wright
RV-10
Message 27
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Subject: | Re: microphone noise |
--> AeroElectric-List message posted by: Ken <klehman@albedo.net>
Thank you Charlie and Barry for your thoughts.
It seems that it is cockpit noise that the mic is picking up.
Interestingly I have a flighttech intercom which uses a hot mic and
processes the mic audio to remove the cockpit noise from the intercom.
That works well and there is no noise in the intercom. However when
transmitting, the mic signal (and noise) goes directly to the radio and
is transmitted regardless of whether the intercom is on or off..
Speaking loudly helps for the time being ;)
Ken
Charlie England wrote:
> --> AeroElectric-List message posted by: Charlie England
> <ceengland@bellsouth.net>
>
> Ken wrote:
>
>> --> AeroElectric-List message posted by: Ken <klehman@albedo.net>
>>
>> Good day.
>>
>> I've tried a couple of headsets but I have a lot of static whenever I
>> key the transmit button with the headset microphone plugged in. I can
>> hear it on my headset and it is being transmitted. No static if I key
>> it with the mic unplugged. So it would seem that the mic is picking
>> up cockpit noise. However clasping my hand over the boom mic or
>> changing its orientation does not change the static which seems to
>> suggest it is not cockpit noise. Any suggestions?
>>
>> This is an Icomm A-200 radio and an intercom but bypassing the
>> intercom with its "pilot/all" switch doesn't change anything. The
>> headset jacks are mounted in a plastic box. Separate shielded wires
>> are used for the mic and the earphones with the shields carrying the
>> grounds.
>>
>> thanks
>> Ken
>
>
> If you have a noisy cockpit, covering the mic with your hand probably
> won't make much difference.
>
> Is it electronic static or cockpit noise?
>
> Does it change in pitch with engine rpm? (ignition or alternator)
> Is it quiet it you key the mic with the master & all accessories on
> but without the engine running? (cockpit noise)
>
> If it's there with the engine & all other accessories off, you might
> have radio problems.
>
> If it's there but quieter & no pitch change with the engine idling,
> it's probably cockpit noise.
Message 28
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Subject: | Re: microphone noise |
--> AeroElectric-List message posted by: Charlie England <ceengland@bellsouth.net>
Ken wrote:
> --> AeroElectric-List message posted by: Ken <klehman@albedo.net>
>
> Thank you Charlie and Barry for your thoughts.
>
> It seems that it is cockpit noise that the mic is picking up.
> Interestingly I have a flighttech intercom which uses a hot mic and
> processes the mic audio to remove the cockpit noise from the intercom.
> That works well and there is no noise in the intercom. However when
> transmitting, the mic signal (and noise) goes directly to the radio
> and is transmitted regardless of whether the intercom is on or off..
> Speaking loudly helps for the time being ;)
>
> Ken
<snipped>
Check with the headset maker on whether the mic has a gain control
(usually a screwdriver-adjust miniature potentiometer in the mic
itself). Also ask the comm radio mfgr the same question; there may be a
mic amplifier gain control in the radio (also a screwdriver adjustment)
as well.
You can achieve better *system* signal to noise ratio by lowering the
mic gain & keeping it as close to your lips as possible. Lowering the
gain lowers the noise volume & keeping the mic close raises the signal
volume. Result: better system signal to noise ratio.
Message 29
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Subject: | Re: Help needed: continued strobe noise & weak radio |
--> AeroElectric-List message posted by: "europa flugzeug fabrik" <n3eu@comcast.net>
This sounds like two separate problems. I wouldnt discount the fact that the strobe
noise heard in audio is coming from the 14V power supply to the comm.
The hint is in more noise heard when you xmit, but youre listening to sidetone,
not regular receive audio. That circuit (potentially part of what modulates
the RF signal when you talk) may be fed by a power-supply circuit within the XCOM
which is inadequately filtered. Nor is the power supply for receive all that
great either, as described.
So, add what XCOM forgot. A external filter needs an inductor (choke), in addition
to a capacitor, as explained by Brian. If the Pep Boys item has a choke,
it may not be adequate. A big capacitor alone cannot filter high-frequency or
sharp-spike noise too well, nor will value matter that much. I fixed a noisy
(via alternator) audio panel with a choke from a bunch of wound toroid cores
from a surplus electronic junk store. I used the one which worked best, probably
one with a lot of turns. Added a cap of arbitrary value (the one in the audio
panel wasnt very big), and all was well. Its possible a toroid donut is
superior to a big transformer-like choke, which I think Radio Shacks version was
like.
Antennas are reciprocal, and you dont say how well you receive. If you can receive
within spec, you can xmit. At around 3500 AGL, with reasonably flat terrain
in between, you should hear airliners gettin vectored down low at a big airport
about 100 miles away. Even 75 is passable, so then the problem is not in
coax or antenna. Leaving the XCOM as culprit on weak xmit.
RG-400 is 50-ohm, and will work fine. Though not superior enough (except longevity
in service) for fixing VHF problems.
Fred F.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=47745#47745
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Subject: | Main bus wire feed |
I was reviewing the Z diagrams in Bob's book and am curious about the
circuit protection coming into the cockpit from the battery contactor. There
is an ANL fuse shown between the alternator and the batt contactor, but
there is no fuse on the (typically) 6 or 8 ga wire coming from the batt
contactor into the cockpit. What is the reason to not protect such a large
wire as it goes through the firewall? I'm sure Bob has thought this through,
I just don't know the reasoning behind it and am hoping someone here might
know. Thanks. Steve
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Subject: | Re: Help needed: continued strobe noise & weak radio |
--> AeroElectric-List message posted by: "europa flugzeug fabrik" <n3eu@comcast.net>
FLYaDIVE(at)aol.com wrote:
> CRIMPS! You do not want a crimped coax.
>
> NO self-respecting RF Man will accept a CRIMPED coax.
>
Why do you say that? You mean a soldered, and hex-nut BNC connector fashioned
by a homebuilder wil be better? On avg, don't think so.
Fred F.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=47747#47747
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Subject: | Re: Help needed: continued strobe noise & weak radio |
--> AeroElectric-List message posted by: "europa flugzeug fabrik" <n3eu@comcast.net>
luckymacy(at)comcast.net wrote:
> BTW, after I originally bought and installed the Xcom radio, they revised their
drawing and FAQ section to REQUIRE owners install a 22,000 uF cap betwee the
xcom and it's power source near the radio.
If Microair said that's a fix, they're admitting to bad design of the XCOM box.
At high freq, diminishing returns, that big, I propose. Simpler ways to fix.
Fred F.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=47748#47748
Message 33
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Subject: | Re: Help needed: continued strobe noise & weak |
radio
--> AeroElectric-List message posted by: "B Tomm" <fvalarm@rapidnet.net>
Lucky,
It would be interesting to power the strobes from a separate battery with no
shared ground to isolate the path of noise source.
Bevan
-----Original Message-----
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of europa
flugzeug fabrik
Sent: Sunday, July 16, 2006 9:00 PM
radio
--> AeroElectric-List message posted by: "europa flugzeug fabrik"
--> <n3eu@comcast.net>
luckymacy(at)comcast.net wrote:
> BTW, after I originally bought and installed the Xcom radio, they revised
their drawing and FAQ section to REQUIRE owners install a 22,000 uF cap
betwee the xcom and it's power source near the radio.
If Microair said that's a fix, they're admitting to bad design of the XCOM
box. At high freq, diminishing returns, that big, I propose. Simpler ways
to fix.
Fred F.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=47748#47748
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