On Mon,9/7/2015 3:36 PM, Mike Smith VE9AA wrote:
I've seen the K2TR stubs, K1TTT page and have recently bought the FB book by
W2VJN
Today, for a change, I had a little spare time so built 2 stubs, but lets
just concentrate on one.
It was supposed to be for the 40m transmitter.
I roughed out the length, attached a T and my antenna switch (a la VA2UP
method) (which I'll only use for stubs, trimmed it with my AA-230pro
and when it's inline (parallel to my primary antenna switch) I see no
difference at all on 20m or 15m on my 2nd receiver when the stub is in or
out of line
The link below is to a piece I wrote on exactly this topic for the most
recent NCJ (National Contest Journal).
k9yc.com/LocatingStubs.pdf
It is in response to an earlier piece by W2VJN, in which I found some
important errors. After batting it around with the "brain trust" (N6BV,
N0AX, AE6TY, AC6LA, and George), I wrote the piece. Most of George's
book is excellent, and I've found those parts quite useful.
I suggest that you study it until you understand all of the fundamental
concepts. Depending on your technical background, you may also need to
crack the ARRL Antenna Book on the topic of Transmission Lines. :) You
might also find k9yc.com/Coax-Stubs.pdf helpful.
73, Jim K9YC
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