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I thought about interference, and tried turning off the workbench computer, and the fluorescent lights, no change. Just tonight I decided to clean the bench, so I put the chassis back into it's cabinet temporarily, and connected it up to the original Super Beam-O-Scope antenna. The radio is now located away from other running electronics, and it still has this whine. Seems to only happen on strong signals. I'm thinking there's something wrong with the AVC circuit here, since the AVC also doesn't work very well.
There is also a pretty constant background crackle. It's affeted by the volume control and is always present. This set is too early to have "silver mica disease", correct? All octal tubes, early 40's I think. It uses the large style IF cans with the brass adjustment screws.
-Ian
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