This is a common problem with just about all crt projection tv's. Usually it's because of the amount of heat the convergence IC's make. There are two IC's that control the horizontal and vertical convergence. If you know how to solder, it's a relatively easy/inexpensive fix. Most repair shops will either order the two chips and a few extra parts and just replace them, or they will order the whole board (which usually costs way too much). You can probably find the two IC's for ~$25 total. Look into it if you have a projection crt television.

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