This circuit was found in the February 1983 issue of Radio Electronics magazine. It is a 4-digit circuit with dedicated integrated circuits, with no power supply indicated.
This power supply with several transistors can supply a current of several amps and a voltage of...
Found in a 1967 EEE, this circuit oscillates at 20 MHz according to the values of the given...
We found this circuit in a 1974 technical documentation. The circuit can be made with BC549...