It looks like the sensor that detects the end of records on my SL-1700MK2 was damaged by the prior owner. The service manual doesn’t give much detail on this sensor, but I believe it uses a metal “shutter” that moves with the tone arm through an optical sensor. It seems there is a series of parallel slots cut into a piece of metal attached to the “shutter”, and a matching piece on one side of the optical sensor (I guess the receiving side) to generate a series of pulses for the control circuit to calibrate itself to. Problem is the piece with the slots on the sensor has been attached on 2 sides with weak joints, one of which had been broken.
Any opinions on my assumptions of how the sensor is supposed to work, and / or advice on repair?
Thanks as always!