Been away all day Ken- just back. If that? CW signal is producing multiple sigs ?on the spec an then it should be easy enuff to check if they are harmonically related to the fundamental. I see you are using 3MHZ RBW so incidental FM etc on the sweeper output shouldn’t be causing any confusion. If you have multiple sigs, see if they reduce significantly with higher freq ?ones reducing the most when you drop the input to the spec an. They may not, but worth it to check. ?If they do reduce then its just? an overdriven spec an mixer causing much of the issue. ??If they are NOT harmonically related to the ?CW sig ex the sweeper then ?you probably need to dig further into the 8350/plugin. Do you get much the same result with the CW sig set much higher, say to around 600 MHz?

?Not sure all ?this addresses your original issue where the signals on the spec an were all a more or less constant 120 MHz or so apart up to 1.8 GHz- but sort this one first. ?

?DaveB, NZ

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