Found in the June 1987 issue of Radio Electronics magazine, this circuit uses well-known CMOS components. The circuit has a CMOS amplifier stage that drives a small speaker.
Mouser Electronics is now shipping DA14585, a kit for the development of voice remote control...
This circuit consists of a low-pass filter for the frequency of 440 Hz. The filter therefore...
This circuit is from an American documentation from 1976. The FET can be the BF245 or MPF102 and...