This 1/2 hertz high selectivity filter was found in the December 1990 issue of Radio Electronics magazine. The source must be symmetrical. The capacitors can be changed for other frequencies.
This tuning-free circuit was found in an old operating amplifier manual. The setting can serve as...
This oscillator uses a ceramic resonator to determine the frequency. This kind of element is found...
This circuit is like the previous one except that it can be triggered electronically. The circuit is...