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 1990s, this simple circuit excites a LASER diode. The...
This circuit was found in an old American documentation. The integrated circuit used is uncommon...
This circuit was obtained from the February 1990 issue of Radio Electronics magazine. The circuit...