Found in a 1967 Ferranti documentation, this circuit uses a LDR from that time as a sensor. Transistors can be replaced with modern equivalents.
This traditional metronome configuration uses unusual transistors in the original version, but it...
This circuit is from an old operational amplifiers manual. However, the setting applies to modern...
Suggested by Fairchild in a 1980s publication, this multiplier uses operational amplifiers from that...