Suggested by a 90s EDN, this circuit supports almost any LED as a source and a phototransistor as a detector. The circuit operates with a PLL 567 at a frequency of around 40 kHz.
To obtain triangular signals, we have the circuit in the figure that uses two amplifiers. One of...
This circuit was found in an old Electronic Design. It makes use of sidacs and operational not very...
This circuit was found in an American publication from 1969. Transistors are from the time and can be...