Hello, I'm TV Tech1 and I'll be working with you to identify and help you resolve your problem.
Half the picture resets itself? Do you mean that you watch TV and maybe the left and right halves of the picture show you the difference between a certain feature being turned off, and on the other side it shows it turned on? Then it stops for a period showing you a normal picture, then it repeats the split screen comparison?
If so, that TV set may still be in Store Demonstration mode and it needs to be set to HOME mode.
Is that what you're seeing on your TV set?
Or are you seeing a normal picture on one side, but half of it is looking like it's got a frozen picture and maybe some squares of picture on it like this --
That's a bad signal from an Aerial, and the picture can't lock in. It causes the picture to freeze, sometimes loses sound and you get either SOME squares in the picture, or like this one, it's so bad the whole picture is a bunch of squares.
If you have a digital camera, you can add pictures to your post by clicking on the paperclip button just above your response box.