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CRT repair?
Posted by: agent_js03 on 2018-02-08 10:31:10
Hi all,

I am having issues with my  best CRT monitor. Basically it started with random refreshes/zaps, it would happen sporadically while I am using it. But then I started having an issue where there would just be no picture. The light would turn green but the screen would remain black. I know that the tube is still good because of how sometimes I still get a picture. I thought it might be the video card, but I plugged the computer into a different monitor and it worked fine. I am wondering how hard it would be to fix something like this. It sounds like maybe a bad relay or something; or if it is blown caps then that is easy to fix. Anyone had experience with this  before? I had it  happen to an old CRT and I put that one in recycling. I just got this monitor a couple of years back and never had problems with it until I started using it again a few weeks ago. It is a really nice monitor and I would hate to junk it.

Posted by: Gorgonops on 2018-02-08 11:35:17
It could be bad capacitors, but the smart money is probably on the insulation in the flyback transformer breaking down. If you can find a model number on the existing flyback you might be able to find a new one on eBay, going rate seems to be between $20 and $40.

Posted by: Scott Baret on 2018-02-09 20:59:51
Tubes are rarely the culprit. As stated above, flyback transformer and caps are the two things to check (in that order). If you have an identical monitor or can source one, swap the boards from it to rule things out. 

Posted by: techknight on 2018-02-10 09:13:37
Sounds like solder joints on the flyback. Seen it many many times back when these things were in common service. 

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