RCA picture problem -- amateur desparate for help

[cliffale]

I am a garbage man and one day on our route, a customer had given me a 37 inch RCA. He told me it had a problem but I was welcome to it if I wanted to have it repaired. The problem is this: when I plugged it in and connected it to cable, the picture and everything is perfect but after a while (the time is always different, from a few minutes to an hour) the picture goes black. I can still cycle through the channels and access the menu and hear the sound perfectly, also see the chennel numbers displayed on the screen but no other visual except a slightly lighter black screen for a split second every time a channel is changed. after another while, the picture comes back in -- a crisp beautiful picture with no jumping or snow or anything and on it goes. The model number is F35665 and it says on the front Entertainment Series, Guide Plus, Picture-in-Picture. I don't know anything about televisions but have worked inside various electronics and computers and I am not afraid to try unless I'm advised that it's just too difficult for the common person. Does anyone have any advice on what I can do or try that may fix this problem? I would be DEEPLY indebted.

Thanks,

Cliff
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