This circuit produces the sound of a motorcycle or an outboard motor. The frequency is adjusted in the pot. For supplies above 9 V the BD136 must be equipped with a small heat sink.
Suggested by an American publication, this circuit has 5 operating conditions indicated in the...
This circuit includes the power supply from the power grid. We found it in Radio Electronics from...
This 10 kHz filter is based on a 741 operational amplifier. The circuit is from Electronics Now...