Have a panasonic TC-L42U12 no power or sound or picture .I think it is a fuse . Not sure where to buy or what number on the fuse .tv is in Ehrenberg AZ . Not a lot of stores out there .please help

You can get fuses just about anywhere. The fuses on the power board are not specialized. However, chances are if the fuse has gone, it will go again. Usually something takes the fuse out. So it's possible you have a bad power board.

Do you have a red standby light? Does it blink? If so, how many times does it blink? Does it only start blinking after you push the power button? Or does it blink right after plugging it in?

Nothing no blinking light nothing!!

Did you check the fuse for continuity, or power in and out?
Sometimes the writing is Extremely small. Look very close with a magnifier.
DigiKey should have it:
http://www.digikey.com/?curr=USD
Knowing the length and diameter will help.

Yep, as Strat mentioned, it'll be printed on the fuse itself. Also check it for continuity with a meter. If you don't have continuity, then the fuse is bad.

We can't tell you exactly what size the fuse is without at the very least knowing which fuse it is. There are about 3 standard fuses on the power board of that model (if I recall correctly).

Thanks I'll just order all three that way I have them with me .when I go to az... thanks