Bob,
Since your antenna seems to be working fine for transmitting, it should
be good for receiving too. The easiest way to check the receive
function in your radio (indirectly) would be to connect your antenna to
a known-good handheld radio in flight, and compare the reception with
your other radio.
When you say "reception disappears," it suggests that the radio goes
silent, which would be a function of the squelch. I assume you have
turned it down (or off), and the real problem is that you still can't
make out the transmission. If the signal is masked by a hissing or
rushing sound, the receiver may lack sensitivity, since the antenna
seems to be okay. If the noise is some kind of buzzing, clicking or
whining sound, you have interference from something else in the
airplane, so try turning other things off one by one, including the
alternator, if possible. If the signal is strong enough, but it is
distorted or garbled, it could either be a receiver problem or a strong
interfering signal.
Dave DeFord, A135
Bob.Harrison wrote:
> Hi! Guys.
> Time for a bit of "traffic" incoming to me for a change ?!
> I have a sparkling new ICOM IC-AC200 radio communication set new head sets
> and new Sigtronic SPA 400TSO Intercom. My aerial is the usual copper tape
> one up the rear of the fin close out c/w toroids as required,
> and it has been trimmed using a VSWR meter by a professional .
> I can transmit "fives" from just about anywhere but reception disappears
> at about 5 miles 1000ft. Same problem travelling to the ground station as
> away from it. Parked in the garage at home it picks up "Airwaves" messages
> from Flight level 35 and even Volmet.!
> We have tried flying with the GPS off, we've not yet switched the
> transponder on, but not tried with the strobe off.
> The co-axial runs down Starboard side with the trim power wires.
> Anyone got any ideas why the transmission is so pathetic.?
> Any contribution gratefully received!
> Regards
> Bob Harrison G-PTAG
>
>
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