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.
Texas Instruments' low power operational amplifiers OPAx196 can be found on Mouser Electronics....
This circuit operates with input voltages from 50 to 140 V providing an output of 12 V under...
This circuit mimics the sound of a siren when we turn the axis of the small DC motor. The...