This circuit is from an ancient American documentation. The integrated circuit is 741 and the power supply must be symmetrical. The passing band is centered at 1 kHz.
We found this circuit in a 1968 Electronics World. The transistors are from the era and...
There are several manufacturers of the integrated circuit used and it also admits equivalents. The circuit...
This circuit is from 1971 American documentation. Transistors are still common except for 2N2060...