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Just returning from vacation....needed one after working on this set! I tweaked the controls and it did seem to improve the situation though I still could not get things right. At the same time something else happened and it has me perplexed:
There will be a "rapping" noise that will start to come, apparently from the HV section. Coinciding with this will be ragged white lines on the screen, sort of like retrace, and a darkening of the raster. As the picture darkens (this is probably a red herring) the color will appear, if weakly) then the raster (the HV, too, I am mostly certain) will dissappear. Soon it will come back to normal. Sometimes it keeps up the cycle and sometimes it behaves itself for awhile. The only unusual signs I see are: once there was a spark inside the horiz output tube just as the HV came back; on several occasions as it came back there was an ugly blue spark in the neck of the crt. I can make guesses: change of IF frequency has messed something up in horiz osc. frequency (doesn't seem likely) or a bad flyback(I can't see anything happening in there, but hard to really tell) or an internal short in the crt or one of the HV tubes? Anyone care to guess? I'll bet some of you, who really know what your'e doing, will have the answer!
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Bryan
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