This simple circuit for headphones or small speakers was found in documentation from the 90s. The circuit works with voltages from 5 to 9 V and has good gain.
This circuit uses components of the time. We found it in a 1968 US documentation. The delay is 100 ns...
This circuit compresses the dynamic range (amplitudes) of an audio signal. The circuit is passive and...
This circuit is from an Argentine publication from 1973. It provides a signal to an amplifier from...