TV has sound..no picture Philips DPTV335 was working fine and suddenly picture went out. Still has sound but nothing on screen (volume bars, picture)

This is a projection TV. No picture can have a whole host of causes.
When the TV turns on, you can see background dimly but no picture.
Caused by the picture being muted. Perhaps the video signal is too fast - 1080i on a TV that does not support it might cause this.
Menu works but no image.
Definite picture muting. A bad video cable, no video from the device providing the picture. From the tuner, the signal circuit board needs repair.
No background, no image, no menu
This is a loss of high voltage to the picture tubes. If the picture cannot draw up and down or side to side, this will happen. Definite time for a repairman. Can be pricey if certain parts have blown out.
Most likely is a loss of vertical drive. (up and down drawing of the picture)