On Mon, 19 Sep 2005 18:07:25 -0400, "Bob Chilcoat"
wrote:


I've tried quick fix by attenuating the input signal by trimming
(shortening) the antenna, but this doesn't really help. This was supposed

Bad thing to do and likely didn't reduce the signal as much as you'd
like. Try an attenuator, enough to kill the offending signal. Once
that is known the next step may be easier.

IF the attenuation needed is under 10DB and leving it in is acceptable
your done. Usually local signals are plenty strong enough.

If you need more than 10DB. Try a suckout stub tuned to the awos
at 120.6 as others have suggested. That should be enough as your
listening on 123.

(my Yaesu aviation handheld works perfectly at the same location), but I
have no other (free) receivers handy. I can move the receiver another 50
feet down the fence, which is my next option, but what if this doesn't work?

I'd try that first, distance will always help the problem. Allowing
for a plastic case on the RX distance is more liklely helpful than
filtering. The problem is the case of the RX is plastic and there is
no shielding so any filter will be compromized by back door entry.
A metalic water proof box with filtered ins and outs for RX and fm TX
will be needed then.

It's possible to make a filter with a steep enough curve for that by
using a bandpass section for 123 and a notch section at 120.6 using
sections of UT141 (.141" copper jacket coax).

Allison
KB1GMX