This circuit can keep a set of lamps on for up to 1 minute, time given by C2 and R2 that can be changed. The load depends on the relay. The circuit is old, from 1988 documentation, but totally viable today.
This circuit was obtained from an American 1980s documentation. The frequency depends on the...
This traditional metronome circuit is powered by voltages from 9 to 12 V and output drives a...
Found in a 1966 documentation, this “coin finder” uses components from the era operating at 2.1...