Re: FDM-DUO overload issues
Many thanks for all the suggestions everyone. I will do some more detailed analysis on this to see if there is some other reason for the issues I'm experiencing. I did have a weird issue with my linear a while back, so I'll try taking that out of line when I get the breakthrough issue again. I just found a Sherwood report on the FDM-DUO and he measured the dynamic range at 70dB. He also mentioned 'high pitched stopband leakage' which is exactly what I get on 40M CW.
"Even more strange is the leakage in the stopband. No phase noise measurement could be
made in a 500-Hz bandwidth when tuned 2.5 kHz offset from the test signal due to filter
leakage. Additionally, one can clearly hear high-pitched leakage out to 9.5 kHz with the
500-Hz CW bandwidth when injecting an S9+40 dB signal (-33 dBm)."