This circuit applies to any common operational, the time constant for the given values being 22 ms. The circuit must be powered by a symmetrical source.
This circuit was originally intended for reading movie soundtracks. The circuit is from 1967 and...
This circuit was obtained in an old magazine from the 1970s. The circuit can still be assembled with...
This circuit recognizes a tone determined by the tuned input circuit (R3 / R4 / C2). The circuit...