These circuits were found in the February 1995 issue of Electronics Now magazine. The circuits have normal response in (a), boost in (b), cut in (c), and plate response in (d).
This guitar pedal was found in a 2004 documentation. The signal is transmitted to an FM receiver...
This circuit was found in the February 1993 Radio Electronics magazine. The frequency depends on...
This circuit was obtained from an American 80's documentation. The operational ones can be...