Throw away this tv?

Question

I have a 21" Sharp TV that is 3-4 years old or maybe even more.At random times throwout the day, the picture disappears and is replaced by a bright white horizontal line across the screen. If I turn the TV off for a count of 5 or so and turn it back on, the line disappears. Sometimes it comes back after a minute or so and sometimes it doesn't. I have not been able to determine whether this is due to circuit overloads or power surges or what.Is this worth repairing or should I just trash it and get a new one?I have A 26" sharp I don't know the model but the same thing happens to mine.