Zenith tv picture jumps after 20-30 min.

this was adjusted by the fine tune on the selector It is the picture not being held in place by being out of tune Same as if the picture goes sideways On the real old units there were 2 knobs to make these adjustments.

What is the exact model number to your Zenith TV?

It could be that the picture tubes have gone down on emission, there is a prcedure that can be tried to bring up the overall brightness but it is just possible that you will loose some picture quality. If it's a 1994 projo tv i am thinking of the three crt system, a gray scale alignment would probably correct the dark condition in your picture, again depending on how far gone is the emission in your picture tubes, if your projo tv is the dlp system, the bad news is that you could be needing some light engine repair. The color adjustment is possible with the availability of a service manual or in the case of the dlp system, light engine repairs or replacement are available from some on line stores.

If this TV is a 25"...then this is an older set. Is the picture dim and the colors dim, will the tint not correct the color scheme? Zenith picture tubes, as a rule, for this model go bad...sorry but this is true!

Check your video cable or any possible switches you may have hit on the remote. Make sure its on the correct setting for the tv.

Your sweep module has gone out. Probably be lucky if can find part for this set.

Bad Light engine cost was 1900.00 sure it is cheaper now.call UED 1-800-648-6657 for replacement cost.

Since this is a CRT based set, there could be a number of problems. What exactly do you mean when you say that the picture fades? Do you loose contrast and the picture gets lighter? or does the picture darken toward black?

Parts are still available, so this can be fixed. If youfeel you want to attempt this yourself, please supply additional info and we'll walk down the diagnosis path.

Dan

Not likely. They probably just need to be cleaned and re-alligned. Rates vary, but our shop charges $20 to do that.

picture is milky white is due to crt.if it is old set. or check video section