This circuit is from a 1966 publication. The frequency depends on the capacitors and on R1 which can have values between 47k and 2.2 M typically. The supply voltage can be between 200 and 300 V.
The circuit in the figure uses two operational amplifiers: an LM101A and an LM102. Diodes admit...
This well-known configuration of the guitar effects pedal was obtained in an English magazine from...
When powering this circuit by activating S1, the lamp turns on smoothly in a time determined by...