panasonic prism w1f (chassis alpha2)

[duncan idaho]

Hi,

I turn on my TV panasonic prism w1f (chassis alpha2)band get a squeek
sound(sounds like an electric razor sound). but nothing comes on.
The channel number shows on the unit but no picture. I can still
change channels with the remote but there is no picture or sound.

Any help would be grateful!

Thanks !