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.
The circuit next to a French publication from the 1980s serves as a reference for fluctuating...
This switched-mode circuit was found in the April 1976 issue of Radio Electronics magazine. The...
This circuit "memorizes" the input voltage that is stored in the capacitor and is presented at the...