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Quick update. Still going through the chassis replacing all of the 1500pf caps in the IF and testing/replacing resistors one by one. What an impossible mess to get at these maddening things. The video IF is a crowded spiderweb full of coils, resistors, petrified insulated wiring I'm hesitant to move and the grounding caps, mostly at the bottom of it all. Fortunately, the ETF had beaucoup service data on this chassis that included a wiring diagram that has been extremely helpful.
The picture has gotten worse but I expected that. The horizontal is going to need to be realigned after all of this is complete. At this point, I don't expect to find a smoking gun where I make a replacement and bang...everything works. The video is now rolling horizontally like a sideways vertical hold issue. Looking at the service data, that's probably due to the phase control slug in T-108 needing adjustment but there are multiple tuning parameters in the horizontal circuit that need to work in concert so attempting to adjust slugs and drives right now to find the magical tuning point where everything is stable is pointless.
Someone has done extensive work on this TV throughout its lifetime and some of the component overcrowding is due to that but most of the IF is original. I don't know how any tech diagnosed and serviced this back in the day. For me, at least, it's a big challenge.
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