This circuit of the 70's uses transistors of the time. The circuit can amplify signals from 10 Hz to 100 kHz and modern equivalent components can be used. The circuit is from Ferranti.
We found this circuit in a 1965 General Electric manual. The components are from the period. Time...
This filter is from 1978 documentation. The source must be symmetrical and the gain in the center of...
This filter was found in the May 1989 issue of Radio Electronics magazine. The power supply must...