In the figure we have a third fast adder that we found in an 80's Electronic Engineering. The circuit can be implemented based on any logic family.
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...