“This unit was MODIFIED to accept an external control voltage through the extra input jack and extra footswitch added to the unit. I have not tested the external Voltage Control function but have verified the voltage controlled filter/envelope follower works. I don’t have the electronics knowledge to troubleshoot or completely test this unit. This is being sold “as-is”.
This is the same circuit as the MAESTRO FSH-1 FILTER PEDAL. Oberheim licensed Maestro to build their similar unit. ” Click here to visit listing on eBay