I checked the voltages at the 4051 key input pins
(13-15, 1, 2, and 5), and they do not look reasonable. Whilst healthy
keys on other 4051's rest at 6V and approach 13-14V as you apply aftertouch, the bad
keys are resting at 9.23V and jump to 15.49V as soon as they are hit,
without even applying the aftertouch. The voltages on some of them
slowly drop back toward 9.23 until you hit them again and they jump back
to 15.49V. Odd.
Message
Re: CS-80 tech question: initial velocity problem on TSB board
2018-01-07 by jonathan4051@...