This unit shipped in and per the customers description, had a dead keyboard and lots of slider issues. The sliders in here are rare, and the worst one was a dual slider type that could not be found anywhere. All sliders were found to be gummed up with old grease, dust, hair, and other debris. The unit had to be deep cleaned, and all sliders opened, cleaned, and lubricated.
The keyboard was giving a large negative CV out, so off the audible scale. The customer said it worked until he tried to clean the contacts due to a few bad keys. What he had done was to over aggressively clean it such that a lot of the CV contacts were dis-formed and resting on the gate bus-bar. These were straightened out, but the majority of keys were then intermittent and badly triggering. Closer investigation revealed that the contact wire that is welded onto the key spring was either missing, or broken at one end such that a consistent on and off point for the trigger and gate could not be achieved. Contact sites were rare and expensive, so it was a case of using the good trigger contacts from some of the contact assemblies to make complete good ones, then salvaging assemblies from my spares RS-09 (fewer keys) to fully populate the 101. This was a LOT of work, but the keyboard is fully functional now and the owner is delighted.
One other note here is that if someone uses the wrong tool on a ferrite oscillator coil slug as a previous repairer did on this one it will crack and not be adjustable in the future.