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Old 09-08-2011, 12:52 PM
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kx250rider kx250rider is offline
REAL TVs have TUBES!
 
Join Date: Oct 2005
Location: Los Angeles & Dallas
Posts: 3,239
Sadly, if the color temp is changing with variance of the brightness, that's most likely a weak CRT. I think that set still has analog pots for white balance setup. They should all be on the CRT socket board.

A quickie procedure to try to set them:

Turn the color all the way down, and turn to a dead channel (snowy screen; not a black screen).

Use a plastic diddlestick screwdriver to set the red, blue, and green background (bkg or cutoff) pots to about 1/3 of the way up from the left (as you're standing behind the TV). Set the drive pots to middle. Look at the screen, and if it's totally black, turn the G2 pot (lower of the two on the flyback transformer) VERY VERY slightly up, until you see the vaguest hint of light of one color. Which ever color that is, turn the other two background or cutoffs slightly up until you have as close to a dark gray screen as possible. Now, turn the brightness and picture up most of the way, and see if the screen has turned to a non-black & white snow... If it's untrue, adjust only the drive controls to balance the whites, and watch the darker areas in case those change from gray. If they do, you can slightly re-touch the cutoffs accordingly, but it's easy to throw it all off. Don't be afraid to do the procedure a few times. But DON'T UNDER ANY CIRCUMSTANCES, turn the G2 pot on the flyback up any more than the tinyest bit, as that will speed up the ruin of the CRT.

If, after you are confident that you have done your best to the the setup adjustments set, and it still loses white balance from dark to light scenes, you probably need to find another set or another CRT for it.

Charles
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Collecting & restoring TVs in Los Angeles since age 10
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