This circuit can use almost any operating system and has a high input impedance. The power supply must be symmetrical. The circuit was obtained in documentation from the 1980s.
This circuit, from ancient French documentation, produces a rectangular pulse from input pulses...
This control is from the Motorola Circuit Applications for the Triac of 1971. The Triacs can be...
This circuit is from 1964 documentation but can be easily implemented based on current components....