Tascam 122mk3 Dead Transport

Discussion in 'TASCAM DIY Repairs and Mods' started by Panagiotis, Aug 11, 2022.

  1. Panagiotis

    Panagiotis New Member

    Jul 2022
    recording gear
    Sorry for the duplicate post, I originally put this in the documents thread.

    I'm working on the transport of my 122mk3 that has no control functionality. Initially I had the typical flashing control lights and indeed had a broken "c" gear which I replaced. I also recapped the motor PCB, I have done several of these successfully in the past. The symptoms are no control function, nor does the capstan motor rotate when the tape sensor is activated (or tape inserted). All motors, including the capstan, rotate normally when outside voltage is applied, additionally, if I manually rotate the head stack to the play position, it will correctly return to its lowered position when the power switch is activated but acts as though it's dead otherwise. I've spent hours trying to trace it down but am lost, might this be a logic IC issue and how do I confirm it?