CRT Monitor with weird random colors

Looks like the degausser is not functioning. Typical rainbow pattern.

Was this monitor dropped?

-- ========================== Jeff Stielau Shoreline Electronics Repair

I've tried to degauss it by placing it face to face with another monitor and repeatedly degaussing the other one (I've read that should degauss both monitors), and haven't noticed any difference. A drop was also my first suspicion, but my sister (it's her monitor) claims it just started up like this one morning. I've got no way to verify the truth on that, so I can't say for sure.

I doubt that would work,,,who knows! LOL

-- ========================== Jeff Stielau Shoreline Electronics Repair

Any suggenstions on how to find out wether the degaussing is functioning properly then? I can't see the OSD menu, so I can't make the monitor degauss itself...

Does it display a picture that is normal except for the colors?

If not, degauss is NOT the problem.

--- sam | Sci.Electronics.Repair FAQ:

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Nope, the screen keeps displaying an image similar to the one I posted a link to. There is nothing even resembling the image that should be on-screen. The color patterns change slightly when connected to a pc set to display different images, but essentially all you get is a rainbow (not nearly as bright as the one in the picture BTW, I increased the contrast of the photo so it would be better visible).

Any input as to what the problem may be then?

OK, it has nothing to do with degauss. If the only problem were incorrect or lack of degauss, the display would have wrong colors that varied across the screen, but there would still be a recognizable picture.

Can you take a photo of the entire screen?

Do the user adjustments do anything?

From the photo you provided, I can't even tell if it's got a raster or just some random blotches of color.

--- sam | Sci.Electronics.Repair FAQ:

Important: Anything sent to the email address in the message header above is ignored unless my full name AND either lasers or electronics is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs.

Here are some better pictures. I marked the corners of what should be the viewing part of the screen with red crosses. The patterns are only clearly visible in a dark room, so it's not that easy to make a clear picture of them.

Jindrich

Hard to say, but for want of a better explanation it looks like the CRT's vacuum could have been lost. If so, the monitor is scrap. Has the monitor been dropped or roughly handled? It's a long shot but I've seen a similar thing once before.

Dave

I forgot to reply about the user controls: they are all controlled by an OSD menu on this monitor, and I can't see it. I pressed the 'menu' button for 10 seconds, which should have reset the monitor to factory defaults according to the manual. I think that's all I can do for now about the user adjustments.

Sounds like a deflection circuit failure is causing the beam to hit the inside of the tube somewhere rather than the screen.

No matter, the monitor is broken and will need to be fixed before the user adjustments are of any use.

"Sam Goldwasser" bravely wrote to "All" (19 Jan 06 11:44:08) --- on the heady topic of "Re: CRT Monitor with weird random colors"

SG> From: Sam Goldwasser SG> Xref: core-easynews sci.electr > Nope, the screen keeps displaying an image similar to the one I posted > a link to. There is nothing even resembling the image that should be > on-screen.

SG> OK, it has nothing to do with degauss. If the only problem were SG> incorrect or lack of degauss, the display would have wrong colors that SG> varied across the screen, but there would still be a recognizable SG> picture. SG> Can you take a photo of the entire screen?

SG> Do the user adjustments do anything?

SG> From the photo you provided, I can't even tell if it's got a raster or SG> just some random blotches of color.

It could be an open or a short either inside the CRT or in the FBK/Focus/Divider. A nearly impossible thing is that the yoke might have slipped off or a rubber wedge fell off tilting it.

A*s*i*m*o*v

... You mean 15" sparks are SUPPOSED to come out of this thing?!?

Kinda looks like the rainbow pattern ya get when you loose vertical deflection on the some of the Philips TV's.

The beam scatters along the edge of the CRT and creates a similar pattern like yours.

-- ========================== Jeff Stielau Shoreline Electronics Repair