Question about Sony KV-21CT1 21" TV

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Problem in Screen display

For the last couple of days, I have been observing different coloured circular patches on different positions of the screen of my SONY make TV. Two of them are observed as violet, one as green & the other as red while the background is white. Kindly provide information about probable causes for such problems & the remedy. With regards, J Roy

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Re: Problem in Screen display

Hi, J ! You didn't say how old you set is, but to me it sounds like you may have a warped shadow mask in you picture tube. A shadow mask could be compared to a piece of screen wire. It's function is to make the electron "beams" from the three electron guns strike the proper phosphor dot to produce the proper color- red-green-or blue. If this is the case the picture tube would requie replacement. Stargazer

Posted on Jan 13, 2007

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