This 300 Hz to 3.4 kHz filter was found in the May 1989 Radio Electronics magazine. The circuit requires a symmetrical power supply.
We found this circuit in an 80's Electronic Design. It makes use of couplers of the time that can...
Found in a 1965 Electronic Design the purpose of this circuit is to control the gain of a stage by...
Employing the XR2206 IC, this circuit was found in the May 1977 issue of Radio Electronics...