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Some updates, but please bear with me, I know next to nothing and am doing my best.
I replaced the diodes with "universal" diodes on the subpower board that tends to be the issue with most sets, but alas, not mine. The TV worked sans-audio for a few hours. The next day, kaput.
However, this time it was no raster or anything. Which I think might be a blessing in disguise because I can at least just follow the voltage, right? Hopefully.
I finally got the chassis mounted in a vertical position so I had access to the backside of the components while everything is connected.
I tested Q4900 which is the auto-shutdown transistor, and it was under at 9.7v. Schematic said if it's over 10v, that will put it in auto-shutdown mode.
So I followed the voltage to T4100, the "VIPUR" transformer (the one before the flyback.) I see the voltage coming in (although both 150v and 130v read as 88.8v when the set is on, then spike to their expected values when I turn off before falling down to zero.) However, on the other side of the transformer is nothing. Zilch. Zippo. And by extension, nothing is getting to the flyback.
I tested continuity on the transformer in-circuit on the "good" side. It has continuity, but resistance. When I test it on the "bad" side, it is OL with continuity.
I think the transformer is bad? What do you guys think? I'm going to desolder it from the board and test it again with the multimeter.
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