I have been chasing an intermittent failure (or a series of failures) in a1998 Panasonic TV. It is Model CT-27G13W, Chassis #AEDP303.
At first it was loss of raster while maintaining normal audio. I did a little probing and a magnifying lens search and found a couple of poor, probably cracked joints, on a pair of heat sinked transistors. I resoldered those and the set worked for about a week.
Then it failed again. This time it lost vertical sweep and audio. It did show a single horizontal line that that had enough variation in intensity to show that video was working. After some more probing (I still have a couple of old alignment tools) everything is restored again.
Now the big BUT. But tapping the printed circuit board produces a quick flicker on the picture that says something else is not quite right.
I haven't been doing much with TV since discrete components and tubes went away so I cannot identify what parts of the board perform what functions. I can find the obvious like flyback, HOT and tuner.
If some kind soul could scan the board layout and post it to one of the sites like Flickr it would be a great help. I am not sure if a schematic will be of great help in this case, but I wouldn't turn it down. If you prefer to email the scans I will post my real userid so that it can be read by humans but not by a system that is just harvesting addresses for their spam.