At 11:07 PM 10/8/96 GMT, you wrote:
>I would like to pick the brain of the experts - I would like to make up
>some coaxial stubs for field day next year to keep the 40 meter station out
>of the 20 meter station and the 20 phone station out of the 20 meter CW
>station etc.
You can use a 1/4 wave shorted 40M stub on the 40M station to keep 40M RF
out of 20 meters. Use two of the seperated by 1/4 wave of coax for 20M and
you will dramatically increase the rejection. I use this arrangement on all
bands at my station.
I make mine by cutting them a little long. Then I put a PL259 on one end.
Hook it up to a T-connector on the output of a dummy load. The other side
of the T-connector goes to my MFJ analyzer. I leave the other end open and
tune the analyzer for 2X the frequency I'm going to null for. You will be
more accurate if you use the 2X frequency and leave the stub open. You
should cut it for minimum SWR at the 2X frequency.
Stubs wont help you in your 20M CW and 20M SSB problem.
73
Bill
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