This is about coax stubs.
Sent this earlier to "Towertalk" then I thought perhaps it was better suited
to contesting.
Reposting, with some edits:
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 (Radio A).
I will add Radio A (transmitter) is using a multiband vertical.
Radio B (receiver) is attached to a multiband horizontal dipole (ZS6BKW) in
case it makes any difference in my question.
I see a signal of roughly S9 or S9+ 20/40 on the receiver (varies per band &
harmonic)
I roughed out the length, attached a T and a 2nd 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
NONE. Like, not even a titch ESP hopeful. (hi)
I presume this is a type 1 stub (shorted 1/4WL type, x velocity factor)
Thinking I had done something wonky, I made another stub from different
coax..same result.
Later I made one up for 20m - same result. No change whatsoever in the
received signal harmonic(s) on the receiver.
Anyone been down this road?
Too close to rig?
Interaction from my T and 2nd antenna switch? Gremlins? Wrong method using
the AA-230 pro maybe? I am close to that 23' mark on the 40m one.
de Mike (SO2R hopeful) VE9AA
Mike, Coreen & Corey
Keswick Ridge, NB
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