We found this circuit in a 1977 factory documentation. The operational amplifiers can be 741 and the symmetrical power supply. Capacitors can be changed for operation at other frequencies.
This circuit has an interesting application. If a device with the selector switch in the 110 V...
This simple radio circuit was obtained in a Japanese publication in 1967. The circuit uses...
This circuit was found in a Popular Electronics from the 90's. The components used are common and...