This is a Sony KV24WX1U (BE3D chassis?) tv, which goes off and displays two
flashs of the red standby led, when the teletext button on the remote is
pressed. For a split second the screen shows text but it looks dropped with
a black band across the top. Also, I see the tv goes off the same way when
the format button is pressed. Please, to suggest what area of the circuit
to check as I am not familiar with this up to date stuff. I have access to
the be3d chassis diagram.
Thanks to you.

David