Rolands last VCO based keyboard synth. MKS-80 is fairly similar I hear. Typical architecture for real analog with cpu monitoring knob movements and updating a patch buffer via a comparator reading current knob and DAC output of memory with an incrementing or decrementing of the value until the comparator changes output state signifying a passing of the equality point. I will study the circuit when I get time.
Roland still stocks many parts for older instruments! You can always order them through your local Service Center and see what happens! Otherwise I have some parts also so don't hesitate to ask.
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