I have a Sony KP 51WS500. When I turn the TV on, the picture is beautiful. However, after 1-2 minutes, the picture "smears" and I have red horizontal lines everywhere.
Sounds like the red picture tube is acting up, there is a voltage control in the front of the tv ..you have to remove the front bottom cover of tv.Depending on model some have screws along the back side,others have 2 screws on the front at the bottom, usually hidden by plastic disks covering the tops.There are wires attached to the front so carefully remove.should be enough slack to just set aside. There is a small door held on with several screws. remove that and you will see the voltage control. It is a plastic square with 6 knobs. Get a good look at it each tube has 1 focus and 1 screen control you want the screen. sometimes the block is put in upside down so that the right knob will actually be for red, and not blue. slowly turn the control to the left, this will decrease voltage. if you turn too far the set will shut off. if it does just twist knob back the other way and try turning on again. You want to turn just enough to make the lines go away. If they won't go away the tubes are shot. If they do go away it might be only a temp fix, usually tubes cause the problem it's just a question of how bad they are. Good luck!