Extremum control systems and extremum selectors therefor

Claim 1

IN COMBINATION, A FIRST SEMI-CONDUCTOR DEVICE AND A FIRST DIRECT CURRENT SOURCE, SAID FIRST SEMI-CONDUCTOR DEVICE HAVING ELECTRODES, AND SAID FIRST CURRENT SOURCE BEING DIRECTLY CONNECTED BETWEEN CERTAIN OF SAID ELECTRODES SUCH THAT A DIRECT CURRENT EFFECTIVELY THAT OF SAID FIRST CURRENT SOURCE WOULD FLOW BETWEEN A PAIR OF SAID ELECTRODES WERE SAID PAIR OF SAID ELECTRODES CONNECTED TOGETHER BY A CONDUCTIVE LOAD; A SEOCND SEMI-CONDUCTOR DEVICE AND A SECOND DIRECT CURRENT SOURCE, SAID SECOND SEMI-CONDUCTOR DEVICE HAVING ELECTRODES AND SAID SECOND CURRENT SOURCE BEING DIRECTLY CONNECTED BETWEEN CERTAIN OF SAID ELECTRODES OF SAID SECOND SEMI-CONDUCTOR DEVICE SUCH THAT A DIRECT CURRENT EFFECTIVELY THAT OF SAID SECOND CURRENT SOURCE WOULD FLOW BETWEEN A PAIR OF SAID ELECTRODES OF SAID SECOND SEMI-CONDUCTOR DEVICE, WERE THE SAID PAIR OF SAID ELECTRODES OF SAID SECOND SEMI-CONDUCTOR DEVICE CONNECTED TOGETHER BY A CONDUCTIVE LOAD, FIRST MEANS CONDUCTIVELY CONNECTING TOGETHER ONE OF THE FIRST SAID PAIR OF SAID ELECTRODES AND ONE OF THE SAID PAIR OF SAID ELECTRODES OF SAID SECOND SEMI-CONDUCTOR DEVICE, SECOND MEANS CONDUCTIVELY CONNECTING TOGETHER THE OTHER OF SAID FIRST SAID PAIR OF ELECTRODES AND THE OTHER OF SAID PAIR OF SAID ELECTRODES OF SAID SECOND SEMI-CONDUCTOR DEVICE; AND A LOAD RESISTANCE INCLUDED IN ONE OF SAID FIRST AND SECOND MEANS SO AS TO BE TRAVERSED BY CURRENT FLOW, IF ANY, BETWEEN THE ELECTRODES CONNECTED TOGETHER BY ONE OF SAID FIRST AND SECOND MEANS, AND SAID DIRECT CURRENT SOURCES HAVING A POLARITY, WITH RESPECT TO CURRENT FLOW DIRECTION, THAT CURRENT FLOW, IF ANY, THROUGH SAID LOAD RESISTANCE, WILL BE IN THE SAME DIRECTION AT ALL TIMES, IRRESPECTIVE OF WHETHER ONE SAID DIRECT CURRENT SOURCE OR THE OTHER SAID DIRECT CURRENT SOURCE CAUSES CURRENT TO FLOW THROUGH SAID LOAD RESISTANCE.