[CQ-Contest] SO2R interference help update

[Dan]

TNX to all who responded. I have a sense of direction and will begin diagnosing.

So far I have transmitted on 40 into a dummy load connected with a short cable with Radio 1 (K3) and listened on 20 with the 1000MP on the tribander. Turning the rotator seems to indicate the harmonic is coming from the shack. Now I will be checking all cable and connectors, unplugging all wall warts and eliminating any antenna switches in the path of the tribander. Probing with my Tecsun SW on the harmonic has not revealed any true peaks on any piece of gear so far but I’m just starting.

If I have a revelation and/or some success I’ll repost with my results.

As an aside I’m making a flow chart to show all antennas and switching for future reference. Amazing how much “stuff” gets added over the years!

73 Dan W8CAR