for the tuning knob, try this.
Get a hunk of line cord from the junk box. take the coating off and
pull out one single strand of copper wire.
insert the copper wire into the screw hole, then the set screw. The
copper will give the threads on the set screw something to latch onto.
If the hole is really bugger up, you may need two strands.
as for the audio bug,
Scope the center wiper on the volume control. I bet the selectivity
switch may just need a good cleaning. A scope will tell if you have
audio at the selectivity control by looking at that center wiper on
the volume control.
if you don't then work your way back towards T2 on the #80356 board.
It's possible with extra large signals, you have some bugs in the d2-
d5 diodes used in the receiver product detector
BTW... miserable board to get out of the radio!
SunLight Energy Systems
The Heathkit Shop
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