This filter has the components calculated for the frequency of 1 kHz but can be changed. The input resistor can be 100k and the source symmetrical. Any operational amplifier can be used.
This circuit emits a signal in the AM range, whose modulation frequency depends on the intensity of the...
This special effect doorbell circuit was found in the January 1984 issue of Radio Electronics...
This 1997 documentation circuit was originally created for use with Camcorder type video cameras....