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OK, latest work has revealed the following:
I thought the horizontal osc was working just fine, but when supplied with a signal with my NTSC gen it refused to lock at the correct frequency. I figured I had some more bad caps, so I made a trip to Chesters. After replacing the rest of the old micas, the problem persisted. I then read out the voltages in the circuit, and every single one was 60 high!
I then had a look at the power supply, where I confirmed that B+ was indeed 60 high (440 vs 385). I'm guessing that selenium rectifiers were grossly ineffecient, because there's no way 5 extra input volts equals an increase that large. Short of always running it on a variac or bucking transformer, I guess I'm looking at dropping it with resistors.
So the question becomes do I get a huge high power wirewound, or insert 2 smaller ones right before the rectifiers?
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Evolution...
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