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Well, I'm pissed. Finally got around to ordering the HOT, power supply IC, and the fusible resistor. I resoldered everything in the horizontal circuit, installed the parts, and turned it on. I have good sound; but, no HV. I have not checked anything else because I'm so irritated at the moment, I might break something. I remember another similar Sony that had no HV. I used an o'scope to trace the horizontal drive signal up to the base of the HOT. The HOT checked fine; but, I changed it anyway and got HV back. On another 27" Sony similar to this, the sound would come up for about 5 seconds, then the set would shut down and the blinking light indicated horiz. circuit shutdown. That one had a bad flyback. I hope mine turns out to be something stupid.
Have also been working on a 2002 27" Panasonic TV/DVD/VCR combo for the Salvation Army (yeah, I let them talk me into it). It has about a 3" picture in the middle of the screen. Looks liky typical bad caps in the vertical circuit. This TV has a stand up board soldered to the main chassis that contains the vertical circuit. You would have thought that they would have made the board PLUG-IN for easier service; but, HELL NO! I checked all the caps and found a 100uf that checked 80uf and a 220 uf that checked 208 uf. I also replaced a 1 uf and a 2.2 uf that looked like they had been hot, even though they checked fine. All of the other caps checked right on. Changed all the caps, resoldered the vertical IC for good measure, soldered the vertical module back in, sat the main board back in it's holder and plugged everything up, turned it on and STILL the same symptom. I think I'll replace the LA7837 vertical IC and if that doesn't do it; I'm done!
I don't know why it happens this way; but, it's always the nice, big, later model TV's that I could get semi decent money for that turn out to be dogs. Let me bring home some POS '82 19" Emerson knob tuner set with cigarette burns all over the case that I would have to pay someone to haul off and I'll have it fixed in 5 minutes. And, I'm not saying all knob tuner TV's are a POS; but, I think you get my meaning.
I'll get back on the Sony sometime; but, I've got to cool down first. If anyone has any information that might be useful, I'd appreciate it.
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