This is the CMOS version of the Electro-Harmonix Hot Tubes from the late seventies. I used the Aion FX schematic, which has some minor differences to the original. Smaller Drive pot, as it's difficult to source pots over 1meg, and some improved power protection and filtering.
ELECTRO-HARMONIX HOT TUBES - VERO LAYOUT
Have you ever experienced any trouble leaving unused pins on CMOS chips floating? I’ve had it happen with CD4013’s - it would lock up after about 30 seconds. The solution was grounding unused pins. It may be unique to that specific chip, but when researching, I found info it’s good practice to pull unused pins either low or high.
ReplyDeleteI was just following the schematic - the inputs of the unused inputs are tied to power on this one.
Delete