On Sun, 23 Feb 2025 11:29:46 -0800
"Craig W8CS via groups.io" <craig_severson@...> wrote:
The noise varied with the digital readout numbers
You could have lead with that. :) That was the next cap I would have pointed you to. It does not fail often but they are getting old. Nice catch.
Here is a quick video ( ) showing this.
Next problem to resolve is that the passband control is all screwed up again. Neither the PBT control nor the PS pots vary the 5.645 MHz signal. I'm inclined to think that it should follow the path of the most recent soldering excursion...(i.e. what did you $%^&* with most recently?)
Follow the control voltages from the fixed passband pots to the PBT/Ref board. All of the switching magic happens in U1001.
--
73
-Jim
NU0C
Jim Shorney