Question about Sharp 20F540 20" TV

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TV problem My TV seems to have three large circles (red, blue and green) on all channels. This means that whilst you can see the picture the colours are distorted into three rings

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Assuming you have a standard TV with a CRT and not a projection set up. Those three circles you describe could mean the CRT has been magnetized. There is usually a "deguassing circuit" that operates only during the first few seconds the set is turned on. If this cicuit is not operating and the set is relocated (in relation to the earth's magnetic field) it could cause residual magnetism in the metal elements of the CRT that could cause the electron beams to be "pulled slightly" away from landing where they should. The picture information itself will be there but the colors can't be right. We used to have large coils called deguassing coils in our tool box to demagnetize and nuetralize this magnetic effect - but then they invented these wonderful built in circuits. If could also be a major problem with the CRT itself. The shadow mask inside it could be warped out of alignment - solution for that is a new CRT. TVGUY

Posted on Jul 26, 2006

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Any chance for a screenshot? The three colors are the three scanning electron guns firing on the screen instead of painting a picture, and yes, this is major repair. Not sure if it will be worth the repair cost, but you could get an estimate if you like the picture the set produces, when functional. Good luck!

Posted on Jun 21, 2006


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