As found on Crate GLX65 combo of 2004, miniature pots with clear plastic shaft and illuminator bulb inside the pot. Independent source that is. For future reference, as in for mechanically broken switch, all the pots are fine. Only 4 years of normal use and yet again flimsey push/push switches are falling apart. Will replace those with robust conventional toggle switches, enough room after bending the pins, and only SPST use although they are DPDT switches.
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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