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CRT Monitor loses Green

My CRT monitor loses the green from time to time. Then the screen is all pink in the background and I can only see red and blue. Just about the time I'm going to toss it, the green comes back and it has the excellent color it's had for years. I really hate to toss it out. I know a fair amount about electronics and have done some tv repair. This is a 15" computer monitor so it's basically a tv without a tuner. Besides that, it seems that the only way to get a CRT monitor these days is a used one on ebay or a garage sale. I really do not want a LCD monitor, they're too hard to see if they are at a slight angle, and because I edit graphics, the low priced LCD screens are just too low in resolution and I can not afford a high end one.

Any idea what might be causing this? The green may be gone for a few hours or as much as 2 days. Then suddenly it pops right back. The screen is not only ugly right now (no green at the moment), but hard to see because it's brightness is reduced without the green. I'll probably his some garage sales this weekend, but I'd still like to see if i can fix this one. Appreciate any help.

Thanks

James

Reply to
jamesw
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Start by checking the cable for an intermittent contact or wire. It could be something as simple as that.

If you have access to another monitor+cable, use them to confirm that the problem really is with the monitor, and not somewhere else.

Reply to
William Sommerwerck

Bad cable or connector likely.

Reply to
PeterD

Start tapping (bashing) the thing with a hammer (well, I used the plastic handle of a large screwdriver :) See if you can locate where the intermittent connection is.

A while back I had a monitor that dropped a colour like yours and even after opening the thing up and remounting every connector I could see, right through to the CRT socket, I never found the fault.

By the time I retired the monitor the case plastic was quite marked in places from the fairly hard bashing I gave it to get the colours back.

Grant.

--
http://bugs.id.au/
Reply to
Grant

(...)

Suggest gently wiggle the video connector on the back.

--Winston

Reply to
Winston

Is it on a KVM? I had one go bad that-a-way.

Jonesy

Reply to
Allodoxaphobia

"William Sommerwerck" wrote in news:hsjp9j$u2i$ snipped-for-privacy@news.eternal-september.org:

often bad solder joints on the CRT socket PCB or wiring from it to the main board.

--
Jim Yanik
jyanik
at
localnet
dot com
Reply to
Jim Yanik

Or a bad CRT socket.

--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.
Reply to
Michael A. Terrell

Assuming that the problem is within the monitor, and not as others have suggested, an external cable problem, then probably 75% of intermittent gun problems are down to bad joints on the CRT base PCB, where the drive amplifiers are usually located. Often, the drys are on output transistor legs.

Arfa

Reply to
Arfa Daily

I didn't suggest that the cable was the problem, but rather that that was where the OP should begin troubleshooting. Has he?

Reply to
William Sommerwerck

Ah, but you weren't the only one who suggested the possibility of a cable problem William, which is why I said "others" ... :-)

Arfa

Reply to
Arfa Daily

You should, as others have suggested, look for bad connections in the signal path. Put a scope on the CRT so you can look for signal when it goes out.

If it turns out to be the CRT, and you've exhausted all other options, you might try hitting it with a stun gun. I've fixed shorted CRT elements that way. Be careful to get all the electronic stuff VERY FAR AWAY so you don't blow up good semiconductors in the process.

Reply to
mike

Yes, I tried. The cable is part of the monitor so I cant just change it. But I did wiggle it around on the back of the computer plug and the rest of the cable. I tried a different monitor on the puter and tht worked fine. I plugged the bad monitor into another puter and it was still lacking green. So, it's the monitor. I just replaced it with another CRT monitor I found at a garage sale for a buck. The new one is a 15" and the bad one is a 17", so I am going to open it and look for bad connectors and the CRT plug, loose solder joints, etc. It's not worth spending a lot of money or time on it, but I'll see if I can bring it back to full color. The last time the green went out, it stayed out for 11 days straight. That was getting real annoying to use. Luckily over the weekend I found this one at the garage sale.

Thanks

Reply to
jamesw

(...)

Have you spritz'ed the video connector with contact cleaner?

If you can locate a loose connector to mate with the monitor cable, you can run a continuity test. Merely 'buzzing' the 'green' pin to the inside of the monitor won't necessarily tell you the complete story.

--Winston

Reply to
Winston

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