We found this circuit in the Encyclopedia of Electronic Circuits Volume 5 from 1995. It uses a 3-terminal transducer from the time. The circuit is triggered by light.
This low-pass filter with 741 op and symmetrical source was found in the August 1993 issue of...
The duty cycle of a Schmitt Oscillator can be programmed by R1 and R2 in this circuit. The...
This circuit is used to test capacitors with a working voltage above 150 V, detecting shorts or...