Seen this brightness drifting issue mentioned against the preset SuperBright modes on the 2070SB but don't think the 2060U has those. Maybe your monitor app messed with the default temperature setup - maybe try a factory reset. Suppose it could be an internal power issue - more white (screen) / more power draw?

http://www.mitsubishielectric.com.au/2351.htm

Service Manual - http://ftp.qrz.ru/pub/hamradio/schemes/monito … nd-pro-2060.pdf

I know this from very cheap as well as from aging monitors.

Damn, this sucks. It's such a great monitor I'll definitely need to hunt down someone with cathode ray experience like an old TV repair guy here in downstate NY.

Thanks for linking the service manual should definitely make it easier.

derSammler wrote on 2020-06-10, 10:09:

I know this from very cheap as well as from aging monitors.

According to your experience, could it just be a power delivery (possibly capacitor related ?) issue or is it necessarily the tube itself degrading ?

I can't speak to derSammler's experience but my CGA Tandy CM-11 is obviously much much older and probably has a lot more run time on it and is brighter than the Mitsubishi. Granted VGA monitor is more complex and so more can go wrong? Still. I never did just get rid of my CRTs back in the day I was a late adopter of LCD. My high res NEC monitor - don't remember the model but it was black - died before my 1998 Dell CRT. In retrospect I wish I kept both of them and tried to get them repaired. I won't make the same mistake with any of the ones I currently have. I will find someone who can tune up, refurbish, or whatever is needed.

Low-res FMV/cutscenes just look SO much better on them. I wish they'd stop trying to push higher resolutions (I don't even want to HEAR 8K) and give us a new display tech that has true multisync like CRTs did.

infiniteclouds wrote on 2020-06-13, 03:20:

I can't speak to derSammler's experience but my CGA Tandy CM-11 is obviously much much older and probably has a lot more run time on it and is brighter than the Mitsubishi. Granted VGA monitor is more complex and so more can go wrong? Still. I never did just get rid of my CRTs back in the day I was a late adopter of LCD. My high res NEC monitor - don't remember the model but it was black - died before my 1998 Dell CRT. In retrospect I wish I kept both of them and tried to get them repaired. I won't make the same mistake with any of the ones I currently have. I will find someone who can tune up, refurbish, or whatever is needed.

Low-res FMV/cutscenes just look SO much better on them. I wish they'd stop trying to push higher resolutions (I don't even want to HEAR 8K) and give us a new display tech that has true multisync like CRTs did.

I wonder if someday a combination of ultra high resolutions and ultra high refresh rates will allow for quasi-integer scaling of low res content along with a simulated line scanning/drawing effect (along with simulated phosphor persistence) that would more closely mimic a CRT . I am not talking about simulated scanlines or pixel shader effects that blur/soften/simulate mis-convergence/simulate screen curvature, but an actually simulated raster scan .

EDIT: Yes I am aware that it would require refreshing the screen at the rate of the actual pixel clock of the simulated resolution (no need for blanking, at least), though it might be sufficient to refresh each simulated line n times per frame duration where n is the number of pixels per line in the simulated resolution, essentially simulating one electron gun per line and offsetting each "active" pixel by one on each following line . So for 320x200 @70Hz , instead of a 4.48 MHz refresh rate, we could make do with a 22.4KHz refresh rate, which is still huge . Hey, I can dream .

Does the geometry also change with this ? I.e image expands with the brightness decrease ? There's a good chance it is caused by HV drop, and it can inidcate weak flyback transformer as I doubt it was like it when new...
Replacing few capacitors on the main power rails can also help a little bit probably not cure the issue.

There are no geometry issues but there are two very, very fine lines that divide the screen into perfect thirds... they are hardly noticeable unless the screen is a single color. I wonder if there's just something going wrong with the monitor? The brightness-on-the-fly issues went away for now, at least.

infiniteclouds wrote on 2020-06-15, 03:21:

There are no geometry issues but there are two very, very fine lines that divide the screen into perfect thirds... they are hardly noticeable unless the screen is a single color. I wonder if there's just something going wrong with the monitor? The brightness-on-the-fly issues went away for now, at least.

The fine horizontal lines are normal on an aperture grille monitor (Diamondtron or Trinitron) .

EDIT : See https://en.wikipedia.org/wiki/Aperture_grille

I don't remember them on my NEC from the early 2003s -- but maybe I just forgot? It's weird that there are only 2 of them. It's great monitor but I'm glad I have a 17" Philips 107E4 that is a shadow mask, as well. DOS games -- particular their cutscenes like the intros to Tomb Raider don't look great on this monitor. Though they look a whole lot better than on an LCD, that's for sure