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 circuit was found in a Delco 1965 publication. Transistors may be current equivalents according...
This circuit was found in documentation from the 1980s. The circuit uses several components of the...
This circuit provides an accurate measure of the internal resistance of an analog instrument. Just...