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Discussion Starter #1 (Edited)
Hello,
I am looking for a CRT technician (or calibration expert who familiar with them) to help me with a puzzle related to CRT monitor (not a TV) calibration with adjusted G2 voltage.
Who can I contact for help or is there any better places to ask such things? I would really appreciate that! Sadly nobody is working on them anymore in my area.
I think those questions are easy for anyone who have experience with them and the main problem here is I don't have much experience with their repair.
It's been two weeks already since I'm renting the calibration device and I still have no clue how to fight that little pesky issue. And it seems that nobody is working on them anymore here either...or at least wont be bothered to help me.
 

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G2 is not meant as an adjunct brightness control. It sets the lower voltage floor at which the CRT just barely begins to illuminate with zero signal being input. It is usually adjusted (in the case of my Mitsubishi 3-gun RPTV) with either an oscilloscope or digital voltmeter connected to certain test points. You may want to PM "Mr Bob" for his thoughts. He is a technician and calibrator who has done a lot of work on CRTs.

I personally wouldn't try to drive that CRT beyond the 50-70 nits you're getting. The phosphors in the tube are likely extremely worn and probably will not last much longer being pushed hard.
 

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Discussion Starter #3
G2 is not meant as an adjunct brightness control. It sets the lower voltage floor at which the CRT just barely begins to illuminate with zero signal being input. It is usually adjusted (in the case of my Mitsubishi 3-gun RPTV) with either an oscilloscope or digital voltmeter connected to certain test points. You may want to PM "Mr Bob" for his thoughts. He is a technician and calibrator who has done a lot of work on CRTs.

I personally wouldn't try to drive that CRT beyond the 50-70 nits you're getting. The phosphors in the tube are likely extremely worn and probably will not last much longer being pushed hard.
Thanks, will try that. Problem is, he is away for at least 7 months already so I'm not sure if he's coming back anytime soon :).
Maybe I'm bad at searching but I can't find anything related to that problem which is weird to me, because it was a pretty common thing to do back in the days to 'fix the brightness/dim picture' on most CRT's...
 

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Unfortunately, just because it was common, doesn't mean it was the right thing to do...
 

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Discussion Starter #5
Exactly why I'm trying to solve this puzzle with help from people who have more experience in this area.
 

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Back in the day, test equipment manufacturers like Sencore made gear that could "rejuvenate" CRTs, restoring some of the luminance lost over time to phosphor wear without pushing the set's drive circuitry to the max. If there are still repair shops that can fix CRTs in your area (they appear to be still fairly common in some areas), they might be able to do such a service for you.
 

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Discussion Starter #7
Maybe somebody who visits this thread know a place or two where I can try to ask such questions? Or a contact of some specialists who worked on CRT and willing to help...I am renting this device and Mr. Bob was away for a few months at least- I am not sure if he will notice my message in the near future.
 

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Discussion Starter #9
Maybe there is a better place to ask such thing somewhere else?

Honestly I am surprised that after 2 weeks I am still stuck in the same place with the same questions...
 

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What exactly is your question? I am missing it in your posts. I can't answer it, but maybe someone can if it's clearly stated.
 
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