Glad to help, if I can...
I have the schematic for that set, but not at hand. The paper tag on the inside of the cabinet shows the main transistor locations, but as you point out, it's best to look over the schematic so you have a good idea what you're looking at in the set.
The circuit breaker will make a "click" that you can feel when you press it if is tripped open, but if it wasn't tripped, it will just smoothly press in and spring out again with no click.
If it's tripped, it's almost definitely due to a fault in the set, so to reset it may or may not cause further problems if the fault isn't found first. Honestly I might try it once, but if for instance the tripler is shorted, it could take out the horizontal output on the second zap, etc.
The horizontal output is a large T03 case transistor located near the back of the chassis near the flyback (from behind the TV, toward the corner close to you on the right). The regulator is on the upright aluminum plate just to the left of the flyback. I'd at least pull out the horizontal output and measure it on the diode scale of a DMM (or on the 10K scale if no diode scale), and be sure it doesn't have a short from collector (case) to either emitter or base. No direction should read less than 1.5K, if I recall. I think there is a damper diode built into that transistor, so it will read funny as compared to a regular NPN or PNP, but no shorts.
I'll see if I can dig up the schematic and post a photo, if I get a chance asap, but today/tonight are out due to Valentine's Day plans
Charles
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Originally Posted by StratLou
That is very cool to know. Was unaware that it was at the tail end of a bygone era. Made in the USA is making a comeback. Look at the Apple Macs soon to be assembled in the US, for ex.
I have tried activating and deactivating that switch (if you mean the one below the on/off switch on the front of the set) several times with no change/effect whatsover.
I am anxious to start the testing but definitely feel I need to study a schematic first to know where all the parts are on the chassis and to know which is which! Thanks for the step by step. There is a circuit breaker on the back of the chassis just below a transformer. How can I tell if it's been tripped? Do I even want to know that at this point? If it was tripped, wouldn't the sound be dead as well?
Can you tell this novice where and what parts exactly on the diagram you're referring to? Thanks.
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Quote:
Originally Posted by ed857
Also, be on the lookout for those early white Zenith safety capacitors.
I think in that unit, 4 or 5 are used in parallel. Zenith PN 22-5001, .0018mf @ 1.6KV.
One or two would open(replace all of them) and run havoc in the Horiz. out and HV stages. Later, Zenith used one cap.(800-860) instead of paralleling .
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Excellent advice, and I noticed at least one or two orange 22-5001s showing in the photo, HOPEFULLY indicating that they were all updated in the 1980s repair. That was a must-do, and Zenith dealers did it free (and also replaced the CRT free if it had been busted by the safety caps opening and sending he HV into orbit). I've seldom if ever seen only a few of them changed, but it's 100% wise to double-check. There should be NO white ceramic tubular caps on the little board beside the flyback, and I think there are two or three safety caps below the chassis near the flyback, which are to be replaced as a set with the ones above.