NEC FS-6391. Greetings group. When first turned on the picture fills the screen, but as the set warms up, the picture can shrink to a couple of cm in the middle of the screen if it gets warm enough.
The nearest schematic I have is for a 6390 but I should the a 6391 schematic soon.
Supply voltages seem o.k. and appear to stay the same as the set warms. Capacitors should improve when they warm up, but I replaced a few anyway.
Using a hairdrier, the most sensitive area seems to be near IC201 (M52778SP A).
I have tried freeze spray, but nothing I freeze seems to change the size of the pic. If the set cools on its own, the picture returns to normal.
Russell Griffiths.