Can anybody help me figure out what's wrong with my TV before I take it to a shop? I have a 1998 color Magnavox, and in the last six months, horizontal white lines have started to fill the whole screen on all the channels, and the menu mode. The picture itself is really bright also. I wonder if it's the white lines doing it. If I knew that the problem was, at least I wouldnt have to pay someone to TELL me first,but just fix the problem. Thanks!

Its a resistor on the tube base gone high, common as mud.

If you adjust the screen pot it will fix it for the moment as it will hide the origional fault. Adjusting things is seldom correct, its just like a coat of paint to hide rotten wood, if that does it for you, so be it.

Screen voltage has gone up to high. Suggest tweeking master screen pot counter clockwise. Check solder connects around flyback. Good luck.