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When they designed this set, they must have been trying to set some sort of record for the number of electrolytics in a TV. They didn't skimp. When I first tackled this set I shotgunned the caps. (I need to start doing just a few at a time-less chance of mistakes). Afterward the set did power up with a raster and audio but then some components started letting out their smoke, notably C5 (an electrolytic with positive to ground, which I wired negative ground like a dope!), C4A (if my notes are right), maybe related to the C5 issue, and R42. As if that isn't enough, something started glowing inside of L30, an IF can in the audio circuit! Okay, one thing at a time...
After some work nothing is smoking. My first issue is, no HV. I really wish I could get my head around electronics theory. Here is what I have going on at the 6CD6 horizonal output:
pin 3 should be 20v but is 2.2
pin 5 should be -26 but is -5.6
pin 8 should be 135 but is 50.
All of the B+ voltages in the set are way high, while the negative low voltage supplies are too low.
I have subbed all tubes in the horiz/hv circuit with NOS, some more than once. The 6CD6 has never shown signs of redplating. There is nothing at the flyback. I have not taken resistance readings. I have a B+K analyst and have tried it to some extent but I'm not sure if it is fully working. I also have a small Sencore sweep circuit troubleshooter which provides a source for horiz osc frequency. It didn't wake anything up. I used that to check the cathode current, which was quite low. I connected an outboard crt subbox in place of the 16GP4 but no luck there, either. So, guys, give me some ideas before I put this back on the shelf for another few years!
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Bryan
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