Using a standard multimeter, this circuit from a 73 magazine for radio amateurs provides an output proportional to the inductance under test. The circuit is TTL and must be powered with 5 V.
This circuit can be used with record players to recover media for CDs and others. The circuit can...
This small audio amplifier was found in an American publication in 1975, The integrated circuit used...
Used with old projector films, this circuit found in Signalite documentation from the 1980s,...