This current switch was found in a Radio Electronics from November 1957. It triggers the current determined by the electromechanical sensor, a polarized relay of the time.
This circuit is intended for charging 12 V Nicad batteries, which corresponds to 10 common...
This type of circuit, found in American documentation from the 1980s, triggers producing output...
This relay without lock uses a general-purpose transistor. The relay is according to the supply....