I have a 10 year old Sony Handycam Video 8mm - Model #CCD-TR91 that has
served us well. The unit is on it's 4th battery, but still works, kind
of... I suspect the trouble is with tape alignment/tracking since some
previously recorded events and sometimes new events as well do not display
properly. Usually I lose half the picture with tracking lines and at times
it also is in Black and White only.

I do not see any electronic tracking adjustments similar to similar vintage
VHS VCRs. Can anyone provide a reference to a service manual or a tracking
adjustment procedure? At this point I am inclined to replace the unit with
another since price has come down so much over the years, but before I did,
I wanted to take a shot at aligning it myself.

Thanks in advance for your help.

Bob