How to fix Panasonic NV-FJ626 grey band of death?
 

My Panasonic NV-FJ626 PAL VCR suddenly started to show on playback this grey, grainy band at the bottom of the video image. Hifi audio has also failed, as well as good quality mono audio.

Attachment 17711

This one is the image produced during pause. The vertical image is tilted downward by the exact margin of the grey band.
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Is this a common malfunction of Panasonic models?

Is there a way to fix this issue by means of repairing?

Kind of looks like a tracking issue that could be addressed by adjusting the tape guides with a screwdriver. Typically, you don't want to mess with the guides unless you are ok with chancing that the alignment won't be correct again, but if it's doing that with all tapes, then it is probably worth trying. There's also the chance that doing a bunch of adjusting can make the guides loosen up over time and make it easier to go out of alignment again in the future.

It's caused by the magnet ring on the head drum that is used for the vcr sensor positioning cracking. It is a known fault in panasonics of this vintage, same thing happened on my NV-FJ621 (which I may have borked by possibly accidentally stripping the threads locking nut before knowing the proper fix, thankfully it's not a rare model or anything, would be worse it it was a svhs vcr). It's fixable, see this video:
https://www.youtube.com/watch?v=pR9MNJbE9vQ