This 1 kHz filter was found in the March 1997 issue of Electronics Now magazine. The circuit is applicable to any operational amplifier with a dual power source.
The integrated circuit can be replaced by more modern operational amplifiers like the 741. The...
We found this circuit in the August 1970 issue of Radio Elecronics magazine. It uses the CA3018...
The configuration shown in the figure is quite simple and can be used to activate a signaling LED...