Pictures don't just get bigger. The only way for that to happen is as Phil said, something happens to the HV, but that only applies to sets with separate HV and horiz. sweep. Your set DOES not have it I can be almost 100% sure. Panasonic simply did not do that any more. Maybe in a Sony or Mits. So no fingerpoken ! (or it's digital equivalent) Plus, Panasonic sevice menus are unfriendly and unforgiving.

What is very likely is that you are watching it through a set top or cable box. Most of the modern cable boxes at least have aspect settings to accomodate newer sets with 16:9 aspect ratios. This is where the problem usually is. With a set top or dable box, go all the wasy thorugh the menus to find things like "aspect", "zoom" and the like.

In case you are not using a set top or cable box, or even if you are, go through the user menu on the TV as well to find similar settings because quite a few of the more modern 4:3 sets also have then, to fill the screen on 16:9 material.

For it to require adjustment in the service menu, two parameters in EPROM would have to increase. Two out of maybe 100.

Ain't happenin.