[Amps] al-1500 parasitic?? or some other problem?

[Vic Rosenthal]

David Robbins wrote:
> 
> At this point nothing is a stupid question, I am definitely confused.

What if the signal is being picked up by one of the other antennas, and some
non-linear device (like pin diodes in a QSK circuit) is generating the signal
and radiating it? (although why a SUB-harmonic?)

I would try disconnecting all antennas except the 21 MHz transmitting antenna
and see what happens.

Also, maybe you said this, but does it happen into a dummy load?

Vic K2VCO