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General Category => Technical Support => Topic started by: eto on 17:09, 04 May 21

Title: CTM644 - red is too dark
Post by: eto on 17:09, 04 May 21
The red color on my CTM644 seems to be much too dark. The dark red is almost black and the bright red is probably what the dark red should be. You can see that in the attached picture.

Green and blue look good (in reality better than visible on the attached picture). White seems to have a slight touch of blue in it (not visible in the picture).

Any idea how this can be fixed? Brightness is already set to maximum. I couldn't find anything about just one color being too dark.
Title: Re: CTM644 - red is too dark
Post by: Bryce on 17:44, 04 May 21
I'd check the contacts on the red pin of the monitor connector / socket for dirt / oxidation first. If they are ok, you can adjust each colour separately inside the monitor.

Bryce.
Title: Re: CTM644 - red is too dark
Post by: eto on 22:01, 04 May 21
there was indeed oxidation but it didn't really change anything. I opened the case and adjusted the red levels. It is now working well. Thanks for the help.

For anybody having the same problem in the future: The resistors are VR80x and located at the edge of the CRT PCB board (end of the tube).