Quote:
Originally Posted by mt999999
Thanks everyone for the help... I hope it is only "minor damage" done. I should have thought more into it, this is the first time I've worked with vintage televisions. I've worked a little with AA5's, but no power supplies in those.
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There are power supplies in AA5s but they are much smaller than those in TVs, since in an AA5 radio there are no very high voltages (in the thousands of volts) as there would be on a television CRT (the highest voltage I've ever seen in AA5s is perhaps 250-300 volts maximum for the B+). Another clue that AA5 power supplies are nowhere near as powerful as TV ones is the fact that many small radios have an equally small rectifier tube; most of the time it's a 35W4 in AC-DC sets, but transformer-powered radios use more robust rectifiers such as 5Y3, 6X5, et al. Zenith radios of the '30s were notorious for power supply troubles (often burned out power transformers) caused by heater-cathode shorts in the 6X5 rectifiers. I believe the company eventually issued a service bulletin addressing this problem, advising technicians to replace 6X5s in these radios with tubes having wider spacing between the heater and cathode to minimize the chance of shorts.
BTW, if the smoke you saw in your RCA TV was white and not billowing out of the HV cage, I would agree with others here who have said that the problem may be no more serious than an old and defective (likely shorted or close to it) filter capacitor venting. Replace that one and any other old caps in that set (as a matter of routine in very old sets such as yours) and it should be OK, as long as you didn't leave it on for any extended length of time after you noticed the problem.
Good luck. I think you will be pleased with the results once you get this set working, as these older sets were built much, much more solidly and had much more conservatively rated components than today's sets, many if not most of which are built in such a way as to push the components right up to their limits. It is little wonder many of these TVs fail after only a short time (read a year or less), as the cheaper off-brand ones. If I were going to purchase a new FP TV today, I'd probably go with either an RCA (because I already have an RCA 19" analog set that has given me trouble-free service since it was new 11 years ago, and still works amazingly well today) or a set in Panasonic's Viera line. I would avoid most other sets with brand names I never heard of like the plague, as one often has no way of knowing who actually built them, let alone the reputation (or lack of it) that company has for quality.