Bass control (CB8722E)

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

Amplifier Speaker (CB26145E)
This circuit can be used as an amplifier for musical instruments or even with your cell phone. The...
Digitally controlled attenuator (CB9029E)
This circuit, which can act as a shield, was found in a 1970s American documentation. The...
Timer CA3140 and 555 (CB14932E)
This timer produces a continuous sound at the end of the timer set in potentiometer RV1. The...