Hi Emma, I suspect the line output transformer or associated circuitry has failed, its not a job for the amateur to attempt.
I would suggest that it would cost more to have a TV engineer come out to fix it than it would to buy a new tv, there are lots of deals out there on CRT sets as people are buying TFT .... talk to your tv retailer, I bet you can get a good deal.
Pete
May 2007
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