Sequential Circuits Pro-One -1981    Weight = ? Lbs. Number mfg.= 10,000 MRP=$995


User Manual: Original version
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: VSE
Circuit Overview: below
Scematics/Service Manual: Hylander's
Common Service Issues/Tips: below
Parts Sources: Keys knobs semiconductors misc
Uncommon chips/modules used:8021 cpu, CEM3340 VCO, CEM3320 VCF
Modifications:Tellun's mods including noise variety, env. invert, etc. or, Midi in kit
General Info Links: Vintage Synth Explorer





Circuit Overview:
     Classic 2 VCO analog subtracive synth with a 40 step sequencer and arpeggiator.


Service Tips:
      Aside from obviously tracing signals around curtis chips and standard aged power supply cap issues etc. I haven't heard of any other real weakness.


A lot of discrete parts in these so let me know if you need anything. A company has created a replacement for the cpu at BMH . ALSO if you have key contact issues watch THIS VIDEO on contact restoration for the LATER models with the strange plastic based contact strips. NOTE I haven't tried this myself and Nick only did it on this unit... Kevin Lightner recommends:

"I'd take this strip and soak it in Tarn-X followed by heavy rinsing afterward. If it's silver oxide causing the probs, I've found no better treatment. (mind you, tarn-x accelerates oxidizing if not completely rinsed away.)



Parts:
A lot of discrete parts in these so let me know if you need anything.
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