I have red coming though when there shouldn't be anyone on the screen. For instance, If I am at a no-input screen I can see some red on the screen.
It is a 1994 Hitachi 50" rear projection TV. I am attempting to fix it up to give it to a family who can't afford to replace their crappy 20" tv, but they are giving me a place to stay over the summer.
any help would be great!
Check the screen (G-2) settings for all three crts, you should be able to obtain a fairly good white balance without retrace lines or other colours showing thru onto a black (no signal) screen. Also, if you haven't cleaned the face of the lens in a while it would be a good idea to open the back up and have a go at that process also. cheers!
Here is a link he emailed me:
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There are typically separate red/green/blue level and drive adjustments in a TV set; get a good grayscale test pattern (I assume you can hook up a DVD and load a test disk) and adjust levels until the black band is without tint, then adjust the level controls until the white band is also neutral (white) in color.
These adjustments are on/near the video amplifier board, and always well labeled (like, with red/green/blue colored knobs). The SCREEN control also may be beneficial, it's likely to drift with time. I'm not sure if you have a one-CRT or three-CRT or LCD or DLP type projector, though...
Projection TVs also will benefit from dusting of the optics.
There are typically separate red/green/blue level and drive adjustments in a TV set; get a good grayscale test pattern (I assume you can hook up a DVD and load a test disk) and adjust levels until the darkest band is without tint, then adjust the drive controls until the white band is also neutral (white) in color. These adjustments are on/near the video amplifier board, and always well labeled (like, with red/green/blue colored knobs). The SCREEN control also may be beneficial, it's likely to drift with time.
Projection TVs also will benefit from dusting of the optics.
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