This third-order Butterworth filter was found in American documentation from the 1980s. Formulas for component calculations are attached to the diagram.
This circuit was found in a 1970 IEEE publication. The circuit functions as a voltage controlled...
Found in a 1968 American documentation, this circuit uses an operational amplifier that is...
This circuit was found in an old documentation from 1968. The voltage gain is 70 and the...