More SWR fun

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I've been having radio transmission problems on my Dittel FGS-2T off
and on since I put it in. Some people say I'm over-modulate, some say
I'm under-modulated. I've got a factory boom mike and a factory wiring
harness. I finally got one of those MFJ-259B SWR analyzers to see if
it's an antenna problem. At 123.4 MHz the SWR reads 2.4. It bottoms
out at around 1.7 at 131 MHz.

Question: Should I worry about an SWR of 2.4? If so, how could I
possibly tune a built in antenna? Also, anyone have any experience in
fixing modulation issues in a radio?

Second issue.

I have a couple of magnetic mount ground station antennas. They both
show a SWR of around 2.1 at 123.4 MHz and a minimum SWR of 1.1 in the
low 130's.

Question: Should I go get longer whips for these to better tune them
for the glider freqs?

Note to all of you trying to tune these kinds of antennas - Having
them magnetically mounted to a steel roof makes a huge difference in
the readings.

[Richard[_9_]]

On Jan 10, 6:00*pm, wrote:
> I've been having radio transmission problems on my Dittel FGS-2T off
> and on since I put it in. Some people say I'm over-modulate, some say
> I'm under-modulated. I've got a factory boom mike and a factory wiring
> harness. *I finally got one of those MFJ-259B SWR analyzers to see if
> it's an antenna problem. At 123.4 MHz the SWR reads 2.4. It bottoms
> out at around 1.7 at 131 MHz.
>
> Question: *Should I worry about an SWR of 2.4? If so, how could I
> possibly tune a built in antenna? Also, anyone have any experience in
> fixing modulation issues in a radio?
>
> Second issue.
>
> I have a couple of magnetic mount ground station antennas. *They both
> show a SWR of around 2.1 at 123.4 MHz and a minimum SWR of 1.1 in the
> low 130's.
>
> Question: Should I go get longer whips for these to better tune them
> for the glider freqs?
>
> Note to all of you trying to tune these kinds of antennas - Having
> them magnetically mounted to a steel roof makes a huge difference in
> the readings.

Andy,

I went through as rash of radio probems similar to yours, it was
driving me and my fellow pilots too ?????? Sometimes it was OK,
sometimes garbled, sometimes not at all, sometime overmodulated. I
changed radios, antennas, wiring harnesses,and boom mics, antenna
wiring multiple times. Even used an external antenna.

The only thing I didn't change was the push to talk. I did check it
with an Ohm meter many times for continuity and it was OK.

It was one of the real nice tactile heavy duty PPT couldn't be
anything wrong with it! Out of frustration I finally changed the
PPT for want of something to do and because it was the only thing that
I had not changed. The problems were solved and I was amazed and in
disbelief ? When I opened the PPT up it was green and corroded
inside. Replacing the PPT solved the problem. So just because it is
simple and has continuity don't assume all is OK.

Richard
www.craggyaero.com