Your problem is the typical convergence problem that happens on almost if not every rear and front , tube type projection TV set. You may only have bad connections on the two convergence IC's or they could be intermittant. These IC's are black in color with white writing on them. They satnd up and are mounted on a large metal plate called a heat sink. They will have the letters STK on them and will have numbers following them. If you are going to replace the IC's, make sure you do not get the inexpensive replacement IC's and also dont forget to use new heatsink compound on the back of the new IC's before installing them, as if you do, not follow these instructions, you will be in the same boat without a paddle in you know what creek in a few months down the road. If you know how to solder and unsolder on small printed circuit boards then you should have no problems in repairing this beast. If you have had no past TV repair experience, play it safe and call in a pro to assist you in this repair. if this is bad connections, the longer you wait to have it repaired, the more of a chance that this WILL cause the chips to overheat and fail, that is if they have not already. Also while you are in there, you should take out the DM board and replace 4 capacitors with newer types that can take the heat a bit better as soon enough you will have the dreaded green light fault. I have instructions for that . Good Luck and let us know how you make out with this repair.
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