Hello and thank you for the question.
There are several problems that could cause this. A failing CRT, a bad Vertical IC, or a failure in the power supply. All of these problems are common with your set, and would require component replacement in order for the TV to function normally again.
Average cost for this type of repair will between $300-$600 depending on which circuit has the failure on the set. Given that a new LED TV
would cost you only around $700 for the same sized TV, I would think long and hard before deciding whether or not to repair this set. Unfortunately, there are no resets or series of buttons you can press that will solve this problem and the set will require component replacement to operate normally again.
If you'd like to have the set repaired, you can use the link below to locate a tech in your area:
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