This circuit was found in a 1967 US publication. In it we have the implementation of a ring counter using only relays. Relay free contacts can trigger indicator lamps or LEDs.
Found in American documentation from the 90's, this circuit activates a 12 V sensitive relay. The...
This circuit, suggested by Motorola, provides a voltage of 15 V under a current of up to 2 A. The...
Among other applications, the 1960 Sylvania transistor manual indicates this timer for chess...