I have a question about my Sony SL-2000 Betamax VCR; that's the little
1982 portable that is the mate to the TT-2000. It's not clear to me
where the best place to ask this might be, so I'm going to start by
just asking here. Just in case, does anyone know if there is a Beta
VCR newsgroup?

My SL-2000 works just fine except in Rewind. While rewinding, the tape
gets loose and flops around until the RH reel slows down and then the
tape goes briefly tight speeding up the reel. This repeats over and
over again. It didn't do this when the deck was new, and I'm sure this
isn't good for the tapes.

Fast forward works just fine.

My impression is that there should be some very mild back tension on
the RH reel when rewinding, but I can't figure out how this should
happen.

I have the service manual, but no VCR servicing experience. I've had
the tape deck all apart and even disassembled the motor. There are no
tension bands in the design, nor are there any friction pads or
washers. My guess is that the braking must be done electrically, but I
don't understand the drive circuitry well enough to know which parts
would affect this.

The motor control is all done by a microprocessor, and the manual is
not clear on what the states of the different lines should be during
rewind. (I'm not clear on this; it's been years since I last looked at
it....)

I fixed a couple of cold solder joints in the matching camera a few
years ago, but those were all for leads which were obviously added by
hand after the machine soldered boards were produced. There's nothing
in this area of the board that looks like that might be the cause of
this problem.

I'd really like to fix this, but I need some advice to get me started
in the right direction.

Thanks for any advice you might have to offer.

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Jim Adney
Madison, WI 53711 USA
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