We have an older Phillips Magnavox tv. The tv will turn on & we will see the picture for a short time but then the screen turns grey. We still have sound, just no picture. Also, the green power light on the front of the tv begins blinking. Any ideas on what is going on with our tv/

Hello, the grey screen could be due to a missing 220Volt source which feeds the color (RBG cathodes)inside the CRT(picture tube). When this happens the beam current inside the CRT goes high in a matter of second, thus triggering the beam current protection circuit(blinking green light)shutting down the TV. Repairing the secondary voltage source is necessary to get the TV working normal, a good technician should be able to repair it for between 80 to 100 dollars parts included, except a picture tube, which could be also the cause of the problem(K-A shorts).