When the 24 V battery voltage drops below 18 V, this circuit cuts off its discharge. The circuit is from 1968 documentation. It can be adapted to operate with other voltages.
This efficient filter against EMI has several coils, being L1 and L2 formed by 100 turns of wire...
This optical sensor circuit for a robot was found in the March 1986 issue of Radio Electronics magazine....
This circuit can provide both positive and negative voltage outputs from 2 to 12 V with current up to...