This blinker for LEDs up to 500 mA was found in General Electric documentation from 1970. Transistors can be replaced with current equivalent types.
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...