I am making some assumtions here. You state that you only hear the AWOS
when a transmission occurs on the CTAF freq. I would think this means that
the receiver is NOT receiving the AWOS signal all the time or it would
trigger
the system constantly. If you listen to the receiver output while at the
airport
does it contain the AWOS audio or just the CTAF audio? My inclination is
that the AWOS sig is being picked up by the interface circuitry between
your receiver and the 88.1 transmitter. If this is the case then more
bypassing
and rf filtering is needed on the interface. Then again I could be barking
up the
wrong tree here, only some suggestions, hope it helps.

Cheers

"Bob Chilcoat" wrote in message
...
Sorry for the crossposting, but I'm looking for more expertise than I
have. I usually hang out in the aviation groups, but am an engineer by
training. I have a radio problem:

I have just completed a special rig for our local airport, but it has a
problem. I took a rather old but serviceable Sony digital air band
receiver (Air 8), boxed it up in a waterproof enclosure and piped the
audio out to an FM microwatt transmitter. The idea of this is that
visitors to our airport who like to sit in the parking lot and watch the
airplanes can listen on their car radios on FM 88.1 to the radio traffic
on our Common Traffic Advisory Frequency (CTAF), which at our airport is
123.00 MHz (AM). Unfortunately, while this setup worked perfectly at home
well away from the airport, we have an Automatic Weather Observation
Station (AWOS) transmitting continuously on 120.60 MHz only 50-60 feet
from the place I need to site the receiver. Even though this is only a 5
Watt transmitter, it overloads the front end of the receiver. As soon as
anyone keys on 123.00 and the automatic squelch is triggered, all you hear
is the AWOS recording.

I've tried quick fix by attenuating the input signal by trimming
(shortening) the antenna, but this doesn't really help. This was supposed
to be a quick and dirty (gratis) job for the airport, and I've already
spent more time and money on it than I wanted to. Any suggestions as to
how I might fix this problem? Cheaply? Obviously a better receiver would
work (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 can't get it any farther away for several reasons. Anyone
have a 120 MHz preselector they can give me? Any really steep (and cheap)
120.6 notch filter designs?

Thanks for any help you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)