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I think that prior to designing the predicta, the man responsible for the way the PC board attaches to the chassis came home to find his wife in bed with a TV repair man, and decided to get revenge!
The main board is recapped, and reinstalled - I got parts for the couplates but didn't bother to install yet, and reaistors checked good on a spot check. I decided changing all the reaistors and rebuilding couplates is more work than removing the board a second time, but could be kidding myself here. The RF choke which power to the damper is fed through went open after reassembly (a bit too much attention from q tips I guess), resulting in no high voltage after I got it all back together. Once I got that figured out I found the break, took off a turn of wire and fixed it.
The sound works now and picture looks promising too. I tested the tubes and found four weak ones and one with bad leakage, so ordered them up and put the predicta back on the shelf.
The grainy image is due to the bad tuner tubes I thibk.
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