This filter was found in an old publication from 1977. The circuit must use a simple two-voltage source and the components can be changed for operation at other frequencies.
The circuit we present was found in an English magazine from 1973. The complementary pair of power...
This circuit that equipped many transistor radios from the 50's was found in an American...
The circuit shown can be used on an infrared audio link. This circuit is from a Popular...