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Hi All,
Just not enough time in the day. Anyway, I have gotten a little time in on the set. Rio and I polished the shroud and it came out nicely. We plan to start on the CRT cover this evening.
Got a lick in looking for the nasty hum. I still can't properly adjust the audio alignment due to a busted slug in A10/11. I have bought a parts set and hope to have a replacement soonish, but it will be some weeks before I pick it up. I don't think it is the alignment, you can see the 'scope trace below. It's just a really cheap digital 'scope. Nonetheless, you can see a clear, loud 120Hz signal and a lot of other nastiness. Things I have done and observed:
Volume control varies hum loudness.
Touching the volume pot reduces hum quiet a bit, although it is still there.
Removed the 3BN6 (audio connector) tube and put a 5 ohm resistor across the socket filament. Hum still there.
Connected an extra 100uF cap across the 140V supply. No change.
It's a new 12CA5. Don't have another at the moment. Old one is gassy and dead.
Cried, whined and complained. Didn't help, no change.
I gotta figure this out. While the picture still needs quite a bit of work, the set is still fun to watch. But the hum SUCKS!
Thanks!
Jonathan
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