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As I've seen others remark before, this Admiral 7 inch set is a much nicer design than some of the others. It has a power transformer and a really nice turret tuner.
This set came to life pretty quickly. Noting a loud AC hum on first power up, I ESR'ed the electrolytic caps and found all five were open. Replacing those and all six of the HV caps (HV filters and deflection coupling) got me an out-of-focus raster. Checking the four 2.2 M resistors in the focus voltage dividers revealed they were all in the 5-10 M range. Replacing those got things in focus.
All of the regular paper caps are still in place, but it has a decent picture, albeit with poor vertical linearity. Sound is OK, but a lot of hum (not sure why off hand, since power supply filter caps have been replaced).
Taking a look at the vertical circuitry, I see lots of 10 M resistors which will soon be checked and replaced as necessary. Then I'll go after the paper caps, working my way from the vertical section outward.
The 7JP4 seems to be reasonably decent. It's a National Union 7JP4, which I'm guessing is this set's second CRT, not the original.
So far, so good.
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