This commercial receiver from the year 1958 uses two AA cells as Power supply. The circuit is intend to receive MW station and the transistors are germanium types not easy to find today.
This circuit is from the SGS manual of linear integrated circuits of 1982. The circuit is based on the...
Found in a Popular Electronics from the 90s, this circuit is suitable for communication between rider...
Indicated as a joke or challenge this circuit shows how it is possible to control two lamps using...