It sat since 1987 after it just quit one day. Here is a list of what's been done to it.
-Power supply completely rebuilt (from PSU in the 80 belonging to Toto. So there is a little bit of "Rosanna" in this CS-80)
-Output hi/lo switch rebuilt
-bad circuit trace repaired causing the pitch to be the same across the keybed
-"Funky 3" preset fixed as it did not sound
-IC replaced on voice 3 mix 2 as there was no square wave (bad IG00158 chip)
-Mix 2 PWM slider replaced
-Ring mod envelope repaired (bad IG00159 chip)
-bad trace on keyboard board causing the AT sensors not to work
-lots of 4xxx CMOS chips replaced
All that is left now is that the VCO aftertouch is not working, nor is the AT speed. From where it was this is excellent. Once this is done it will have a full calibration.
Better than it's looked in ages:

Sub OSC noise:

Sub OSC sine:

Toto's contribution:








