I have a fairly old 27" sanyo that does the same thing. I haven't really figured out how to fix the problem, but I found a temporary cure I suppose. 1) Make sure you have cable, dvd, vcr, or SOMETHING going into the coaxial in the back. You need to have a good signal going to it. When I have my dvd player on, it has to be on channel 4. If not, the channels are snow. Whenever my tv hits a snow channel, it turns off. I let it sit for a couple of seconds, turn it back on, and flip to channel 4 immediately. That usually fixes it. It just has to be on a channel that has a signal going to it. Sorry I couldn't help any more.
DyingDreams
July 2005