We found this circuit in an American 1980s documentation. The circuit uses a piezoelectric transducer unusual in our day. The transistor is general purpose type.
This 1/2 hertz high selectivity filter was found in the December 1990 issue of Radio Electronics...
The two power steps below are intended for use with the SAA1027 stepper motor control but can be...
This interesting circuit, found in a 1986 publication, includes a powerful audio amplifier. Being...