I have a computer (CRT) screen in my possession that has a lightly effected area caused by a magnet. Degauss does not help. A co-worker told me once that he used another magnet to fix the problem. I don't want to do anymore damage to the screen. Any suggestions?
Call your local computer repair shop and ask them if you can borrow their degaussing coil. Search Google for instructions on how to use it.
Or just take the monitor in and let them fix it. It's a 30-second procedure, and if they want to charge you more than $10 keep looking for another repair shop.
Since you didn't post the make/model/type of crt screen, I will guess it has a Trinitron crt in it. In which case a strong magnet may have permanently damaged the aperature grill or messed up the internal magnets that do the baseline convergence and geometry correction.
Since it is a monitor and not a tv set, the actual jigs and time required to correct the problem if a basic degauss did not fix it will not be cheap. Should run around $45-50 to do it right.
Are you sure the crt had not been dropped and the aperature grill or shadow mask warped in one corner?
Did you try degaussing the screen with a hand held type degausser? There is a chance that the shadow mask in the tube has been damaged.
I am assuming that nobody messed with the convergence and purity ring magnets on the rear (neck) of the CRT.
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JANA _____
I believe that it happened during the transport of the monitor from my stepfather's house to my apartment. He just got a new Ford F-150 that has a built in subwoofer under the rear driver's side seat. During transport, he placed the monitor screen down on the seat. After about a
45min trip, I think the subwoofer may have lightly induced the screen. It is only visible on an all white screen such as a MS Word document.The degauss method I used was the degauss button on the monitor itself.
A manual degauss may work then. The caveat here is that a monitor or tv screen generally should never be shipped in a face down position. If a bump had been hit very hard in the truck it still could have (unlikely but possible) jarred the shadow mask or more likely the aperature grille hard enough to slightly warp it, espcially while it was being pulled by a strong magnetic field.
A manual deguass sometimes can be performed with a magnetic tape eraser that plugs in to the ac line. More likely it will need to be performed with the manual big round hand wand. If it is a trinitron crt with aperature grille, whoever does the degauss needs to be aware that too strong of a degausser can damage the tube. In other words they need to start far away with a solid red image on screen and come closer to the tube just past the point where the color purity problem is resolved, then back away to finish the deguass. Never, ever start a degauss on a trinitron tube with the degausser right next to the crt.
An external degauss coil should fix you up, or maybe repeated attempts with the internal one, but let it cool for a couple minutes between tries. The built in ones aren't very powerful.
run an AC mag over the screen in circular motions and with draw it from the center. its most likely that the magnet on the large speaker was near it.
-- Real Programmers Do things like this. http://webpages.charter.net/jamie_5
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