This circuit was obtained in a documentation from the 70s. The operational amplifiers used are uncommon today. Modern equivalent types can be tried out.
Found in a 90s nHands On Electronics, this circuit triggers a relay that shuts off the load when...
This project was found in a 1982 publication, using only two transistors. Signal injectors are...
Designed by Philips in 1968 to control the washer water level this circuit uses components from the era....