Found in a 90s Electronic Design, this circuit is used with a 9 V adapter for powering small circuits. The maximum current is given by the 250-mW regulator.
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...