Quote:
Originally Posted by pac.attack76
I've had it running about 20 minutes and now it tries to shut off. I try to get a video real quick.
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If the set is trying to shut off after 20 minutes, there is definitely a problem somewhere, either in the LV (B+) power supply or the 2nd anode supply to the CRT; I would suspect the latter. Most color TVs of the late '70s on had an HV shutdown system in place to protect the CRT in case of abnormal increases in 2nd anode (ultor) voltage, which can and often will cause x-rays to be generated by the HV regulator tube as well as the CRT. (Remember the color TV x-ray scare of the 1970s?) I'll never forget a picture I saw in, IIRC, Popular Science magazine of the '70s which showed a man who had pressed his stomach right up against the screen of an operating color TV. The caption below the picture read, "This is the spot for a chest x-ray!"
Some of these protection systems shut down the HV immediately, resulting in a black screen, while others caused the TV to display an unwatchable picture. Either symptom demanded that the TV be shut off immediately and not used again until the problem is remedied.
BTW, these problems cannot happen with flat-screen HDTVs; even though there is high voltage on the panel, it is nowhere near the kilovolt range.