The figure shows how to generate a sinusoidal signal using a CMOS integrated circuit. The circuit is from a Radio Electronics from November 1976. The frequency depends on the capacitors.
We found this circuit in a 1987 documentation. It is a multi-tester with neon lamp and LEDs...
This two-tone buzzer can be powered by a solar panel. The circuit is from a 1991 documentation. The...
We found this circuit in a Texas Instruments optoelectronics manual. The audio modulator serves for...