After doing due diligence inspection of the Quad 33 boards and spraying contact cleaner everywhere, saw the broken "U" shape hook at the end of the balance control slider. I may have tried to move the slider too hard as it was pretty stiff, breaking that fragile piece of old plastic in the process.
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| From the internet, as there is no pix of the slider in the service manual |
Tried to purchase a replacement but could not locate any spares for sale anywhere.
Then I had an idea - why not use a strong string of sorts eg fishing line, badminton racket string, or alike - tie a knotted loop around the protruding metal piece (maybe adjust so closer to edge of the slider) and tie another knotted loop around the remaining plastic piece eg resulting in a figure-8 shape.
That did the job - see the pix(s) below.
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| 1st knotted loop, around the protruding metal piece |
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| 2nd knotted loop around the remaining plastic piece |
Will perform a proper replacement ... someday😏
Note: Spraying contact cleaner into the balance potentiometer did restore smooth operation
