The SLP101 has a linear motor tracking sled, so the lubrication of the guide rails is critical.
Takes a very specific grease/oil(Panasonic molytone) to make it work properly. Probably the
cause of the problem. With the unit unpowered, picking up the front of the unit 2-3" should
make the laser slide smoothly from front to back, and vice versa picking up the back end.
Otherwise, needs lube.

--
Stephen Sank, Owner & Ribbon Mic Restorer
Talking Dog Transducer Company
http://stephensank.com
5517 Carmelita Drive N.E.
Albuquerque, New Mexico [87111]
505-332-0336
Auth. Nakamichi & McIntosh servicer
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"Mark D. Zacharias" wrote in message ...
It's not the servo IC. Maybe a lubrication issue, many old Technics models,
including I THINK yours, used direct-drive spindle motors.
The sled drive wormscrews got bad lube and bad belts as well. Of course the
optic should be cleaned.

Mark Z.

"majortom" wrote in message
oups.com...
Don't have any past experience with yours, but could be caused by the
Servo Output IC. Chase the cables that lead from the drive to the main
board, I'm sure the Servo IC will stick out like a sore thumb from
there. Also check in that vicinity for signs of resistors that may have
changed color, most likely not obvious with the naked eye, best to
check them for tolerance. They should be resistors in the circuit
between the IC and the motor itself.