It sounds like you have lost a componant in the (damn memory of mine) area near the main capacitors. For the life of me ii cant remember what it is called. This should be an easy fix for a repairman. I would estimate less than $100.00 including the service call. I could do the repair but I cant explain how to do it.
Unfortunatly I can not recommend that you attempt this repair anyways. It deals with an area of the set that is the biggest reason that they put the high voltage warnings on the cover for. It can be potentially lethal to an untrained person poking around in the area with a solder gun.
As the set is basicly brand new it is well worth the cost to have it repaired. The RCA brand is one of the best on the market and should give you many years of good service.
I realise that I havnt really told you anything you didn't already know but this really is the best solution to your problem.
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