Quote:
Originally Posted by CaryLee
. . . . However, that image of the picture is with the brightness and contrast almost all the way up. Towards the middle of adjustment, it would fade to black. And I will say that the photograph does make the picture appear slightly brighter than it is in real life. But I did take that photo this afternoon, with daylight in the room.
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You just casually mentioned what probably is the best clue yet on your brightness issue.
If the image blooms (it suddenly gets bigger as it dims out) before it goes out, look something restricting the HV current to the picture tube. This is the normal symptom of sudden high voltage drop. The most usual suspects are the 1X2 tubes. And no, you cannot test one 1X2 by switching it with the other one as they work together to form a voltage doubler. *
If he image does not bloom, and the image stays close to the same size, look for the problem in either the video output, DC restorer, brightness control or picture tube circuit or the CRT itself. (The latter is not too likely.)
* If you had a scope, you could confirm that the waveforms and signal level going into the grid of the horizontal output are correct. You really need a known accurate HV meter before you go messing with the HV adjustments.