[amsat-bb] AO-51 Mode J Desense Solution

["hasan schiers" <schiers@xxxxxxxxxx>]

As has been mentioned on this list before by Drew, KO4MA, a VERY simple and
effective solution to the Mode J desense problem is the common duplexers
made by Comet and others.

I put a low noise gasfet preamp up on Friday.  (70cm). It was getting killed
by my 2m uplink signal. I took a spare 2/70cm duplexer I had laying around,
put a 50 ohm resistor on the 2m side, attached the antenna side to my 8
element quad and ran the 70cm side to the INPUT of the gasfet preamp.

Every bit of interference is gone! Way to go, Drew. You should see some of
the contraptions I have laying around the basement from AO-8 days....none of
them work nearly as well as the common duplexer/diplexer.

It shouldn't be this simple, but it is.

...hasan, N0AN
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