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Diagnostics and repair performed by Jareth Lackey of Synthpro Restorations, LLC.
Service included repair of an oscillator that wouldn’t track, a wave shape circuit repair, replacement of two op amps, five interface buttons, oscillator sync switch , one broken key, and the save battery which was recently replaced on a separate trip to Synthpro.
Recently gone through, every function works as they should, and the factory presets were restored due to the battery replacement
The bottom of E4 key is chipped, shown in pictures, and the pulse width modulation slider wiggles loose, also shown in pictures. The slider must be stabilized when using. Despite this, it has a smooth reaction, and is not a wiper or carbon track issue but a broken actuator. It works as it should otherwise.