We found this circuit in the May 1972 issue of Radio Electronics magazine. Its purpose is to teach logic using integrated circuits of the TTL family. The 5 V power supply is included.
This circuit triggers the LED when the monitored battery voltage drops below 9 V for 12 V...
We found this circuit in a Radio Electronics from January 1967. The SCR is already the C106, which...
This power source with silicon diodes at a time when valves were still used was found in Radio...