Bass control (CB8722E)

Found in a 1993 Electronics Hobbyst Handbook, this passive circuit can be used with common preamplifiers and amplifiers.

4-channel mixer (CB8756E)
Found in a 90s Elektor, this mixer makes use of integrated circuits of the time. The supply must be...
Adjustable Current Limiter LM317 (CB15314E)
The maximum current of this circuit is 1.5 A. The circuit has the formulas next to the diagram to...
Pulse Width Discriminator (CB5159E)
This circuit was found in an American 1980s documentation. Equivalent operational amplifiers can be...