Yamaha CS-70M -1981    Weight = ? Lbs. Number mfg.= ? MRP=$2999

User Manual: Yamaha
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 Manual Manor
Common Service Issues/Tips: below
Parts Sources: Keys knobs semiconductors misc
Uncommon chips/modules used: Z-80 CPU2 ea.M51620P/IG00150 lfo chip, Many M51621L/IG00151 VCA's, 12 ea. IG00153 VCO, 12 ea. IG00156 VCF, 12 ea. IG00158 WSC, IG00159 EG/VCA, YM63300 bbd clock, MN3009 BBD, IG03290 bbd drive mod, IG2600 or 2590 VCA, TA7317P
General Info Links: Vintage Synth Explorer

Circuit Overview:
     A more complex 6 voice dual vco/voice subtractive analog synth similar in many ways to other CS series. But improved in the memory department having storage for 30 patches. And a handy dandy card reader!

Service Tips:
     I've never worked on one. But it shares same chips for vco and vcf as other CS series.

I had a most peculiar manifestation shown in a video I did on CS5. The cutoff control would just cease to impact a highly filtered sound at the Ab second from top and below or like that. It would change a note during warmup. Turned out the VCF chip was the issue!

I believe I should have any electronic part or keys for these save exact transformer, etc. Ask if you have need.
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