Moog Opus-3 -1980    Weight=20 Lbs. Number mfg.= MRP=$1995-$965(from ad poster)

User Manual: VSE
Reset Proceedures: N/A
Operating System code: N/A
MIDI or other control protocol: N/A
Software related Links: N/A
Patches or knob settings:
Circuit Overview: below
Scematics/Service Manual: fdiskc archive or synthfool or Manual Manor
Common Service Issues/Tips: below
Parts Sources: Keys knobs semiconductors misc
Uncommon chips/modules used: M083 TOS, TDA1008 Dividers, CA3080 OTA
General Info Links: Vintage Synth Explorer

Circuit Overview:
     Three filter sections from a divide down network. Moog filter in the brass/organ mix and a simple filter for Organ and String with resonance. Pan and volume for each section. And of course string and organ can be mixed into a chorus with a rate switch! Groovy performance bonus.

Service Tips:
     Not aware of a particular weakness on these other than dirty sliders. Actually many of mine got broken by a nit wit shipper who absolutely defrauded me as she agree to ship it my way..then did it hers :-). Once these sliders break there is no off the shelf replacement but I've seen 'chipsforbrains' on ebay sell sets of them..after I went to the pain to repair most of mine and replace one with a near enough retro. These sliders can be pulled apart, cleaned, regreased with conductive grease and various shaft repairs made at times or parts swapped out with other units to create one good one out of two with different problem parts. (EG. one has a broken shaft, the other a worn out resistive coating.) Using soldering surgery techniques sliders with bad connection right a the resistive material interface can occasionally be fixed using springy wire and hemostats!

Have most of the parts here for them electronically.
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