User Manual: Clark's OB-X page
Reset Proceedures: N/A
Operating System code: N/A
Patches or knob settings: Clark's page
Circuit Overview: below
Scematics/Service Manual: fdiskc archive or retrosynth
Common Service Issues/Tips: TC's OBX
Parts Sources: Keys knobs semiconductors misc
Uncommon chips/modules used: CA3086, CEM3310 EG's, CA3080 OTA
General Info Links: VSE
Analog subtractive synths with typical memory scheme but some higher quality conversion of data going on for smoother transitions in the control realm than most. Maybe all of the time. A mod should be done to prevent 4051 mux issues etc. Check out the great resource by Analog Diehard
Just a lot of op amps that can go bad in these of course and OTA's. I've never worked on one though.
Aside from some of the Curtis chips and maybe CPU I stock everything all the time electronically. I've gotten the chips when needed from other techs or off ebay. Knobs may be difficult to find exact replacement. The switches are available from firstname.lastname@example.org I hear.
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