This circuit was found in an American documentation from 1969. It serves to trigger circuits by providing a 7.5 V signal at the output from 500 mV pulses.
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...