If you have the skills and can get your hands on SMD components, you can assemble this small amplifier. We found it in the Radio Electronics Experimenter special edition from 1990.
This circuit was obtained in a General Electric documentation from the 80's, and can be used as a...
This circuit with a dual power supply generates sinusoidal, triangular and rectangular signals. We found...
In addition to tone control, this circuit of the SGS 1982 linear integrated circuit manual has a...