Slow progress in tracking down the noise problem. My glass is 1/2 full so, if I find where the problem is not, then that's progress.
I took out the microphone pre amp completely and the noise remained
Readjusted the carrier along with tx amp and final amp, noise remained
Confirmed good grounds among the various boards
Placed an electrolytic cap at various points and the noise remained
Used tin foil to make a temporary shield for the DDS and Nano boards, noise remained
Use of a battery did not help
So the next step is to solder in caps on all the power points on the various boards and anywhere else one can think of.
As well spent sometime today designing a new circuit board for the pre amp, which includes the AGC circuit. Thanks to Ken VE3ABN, who put together the design for the circuit(s) and got it working.
Looks like I'm going to be cutting it fine getting this rig up and running for Field Day.
73, Peter
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