PANASONIC AG-1970P SVHS VCR with internal TBC 
              WEIRD VIDEO PROBLEM IN ALL MODES  *  04-27-2K

     All modes mean E to E, tape playback, and recordings made from the
tuner or video input. Look for a bad IC3303, a little "module" in a tin box
about the size of two sugar cubes. It's a comb filter on the sub luminance
chroma board, and when it fails, the symptoms are unlike anything I've seen
before, except perhaps a time base corrector gone crazy. The symptoms range
(as it heats up) from a loss of color, to "lines" in the video similar to
bad off-air "skip" interference, to zig-zag tearing of the image, to an
indescribable mess on the screen. No switch or control on the VCR will
change the distortion, by the way.
     It's kind of a pain (what isn't these days) to get to that module.  
Remove the top cover. Remove top PC board (7 screws, 4 top and 3 in back).
Lift up slightly and fold top board over to access sub boards. I find it
easiest to set the VCR on end and prop up the top board for better access.
Unplug one connector, then unplug the sub-luma/chroma PC board, the one just
behind the rear connector panel. It's easier said than done! The sockets are
TIGHT! I made a tool to do the job by forming a thin flat piece of metal
about 6" long and 1/2" wide with a right angle bend on one end to slip under
the board... damn little room in there. When you pull the tool to one side,
it lifts the board (the connector nearest will pop loose), but careful you
don't dig into the mutherboard traces underneath (been there, did that,
cussed the intermittant). Try to put the tool over the wire jumpers on the
bottom board and pry against those as you wiggle the board back and forth
slightly. You may have to use enough force to cut one of those jumpers, so
examine it after you pull the board out.
     Change IC3303... part number is VCR0320 in early versions. Replacement
(and part in later versions) is VCR0369. It is my opinion that the little
SMD electrolytics are what goes bad inside that "module", but I've never
wanted to change them... I always change the module. One last thing... to
make sure that -is- the part that's failing, try hitting it with circuit
coolant while it's running in any mode. The video will go nuts. That module
becomes very temperature sensitive when it fails. As tightly packed as that
VCR is, I'm amazed it lasts as long as it does. Too damn hot in there,
especially for those @#$%^&* SMD electrolytics.

Ray Carlsen
CARLSEN ELECTRONICS... a leader in trailing-edge technology.