This low speed circuit was obtained in a 1966 Microelectronic Design. The circuit has a 10 MHz passband. The power supply must be symmetrical.
This circuit is from an American 1964 documentation. Transistors of the time are used, but modern...
This protection circuit for battery chargers was found in an old Elektor. The relay is according to...
Found in an Electronics Now from the 90s, this circuit is used to control the supply of...