[CQ-Contest] Coax Stubs for SO2R

[Mike Smith VE9AA]

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