This circuit with the NE602 was found in the February 1997 Electronics Now magazine. The NE602 integrated circuit is not very common these days.
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...