User Manual: Yamaha
Reset Proceedures: N/A
Operating System code:
MIDI or other control protocol:
Software related Links: N/A
Patches or knob settings:
Circuit Overview: below
Common Service Issues/Tips: below
Parts Sources: Keys knobs semiconductors misc
Uncommon chips/modules used: YM62100 Key assigner, YM62400 single channel assigner, YM62200 tone generator, YM70200 and YM70300 Organ Generators, 2x YM70400 polysynth generator, IG00157 preset memory chips(?!), IG00159 EG, IG00156 VCF, IG02601 and IG00151 VCA, IG00150 LFO, MN3009 BBD's, IG03290 BBD driver, YM626 delay vibrato gen.
General Info Links: Vintage Synth Explorer
SK series synths I believe are divide down oscillators with some analog circuitry and some digital stuff going on. Anyone have a better description? Hope to get one of these soon.
While Yamaha normally does not keep parts around more than 5 years or so, I have scrap sk20
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