Megohm bridge having a plurality of standard resistors, and calibrated in a ladder-type operation utilizing the smallest resistor (precision) as absolute standard

Claim 1

IN A BRIDGE-TYPE RESISTANCE MEASURING INSTRUMENT COMPRISING A FOUR-LEG BRIDGE HAVING A FIRST AND SECOND ENERGIZING TERMINALS, SAID BRIDGE FURTHER COMPRISING A STANDARD LEG AND AN UNKNOWN LEG CONNECTED IN SERIES ACROSS SAID TERMINALS AS A FIRST BRANCH AND A RATIO LEG AND A BALANCING LEG CONNECTED IN SERIES ACORSS SAID TERMINALS AND PROVIDING A SECOND BRANCH, A PLURALITY OF STANDARD RESISTORS TO BE CONNECTED INTO SAID BRIDGE TO PROVIDE AN EXACT RESISTANCE MAGNITUDE INCLUDING AT LEAST ONE NONPRECISION STANDARD RESISTOR WHICH DIFFERS FROM ITS STANDARD MAGNITUDE SO AS TO REQUIRE CALIBRATION, A PLURALITY OF RATIO RESISTANCE MEANS TO BE CONNECTED INTO SAID RATIO LEG TO PROVIDE RESISTANCE THEREIN, THERE BEING A RATIO RESISTANCE MEANS RESPECTIVE TO EACH NON-PRECISION STANDARD RESISTOR WHICH IS TO BE CONNECTED INTO THE RATIO LEG WHEN THE RESPECTIVE NON-PRECISION STANDARD RESISTOR IS CONNECTED INTO THE STANDARD LEG, SAID PLURALITY OF RATIO RESISTANCE MEANS BEING APPROXIMATELY OF THE SAME MAGNITUDE WHICH MAGNITUDE IS THE RESISTANCE TO BE INSERTED INTO THE RESISTANCE LEG WHEN A PRECISION STANDARD RESISTOR IS CONNECTED INTO THE STANDARD LEG AND EACH RATIO RESISTANCE MEANS RESPECTIVE TO A NONPRECISION STANDARD RESISTOR BEING ADJUSTABLE TO COMPENSATE FOR THE DIFFERENCE OF ITS RESPECTIVE STANDARD RESISTOR FROM THE PRECISE MAGNITUDE THEREFOR, CONNECTING MEANS FOR INDIVIDUALLY AND SELECTIVELY CONNECTING EACH STANDARD RESISTOR INTO THE STANDARD LEG OF SAID BRIDGE AND FOR CONNECTING THE RESPECTIVE RATIO RESISTNACE MEANS INTO THE RATIO LET OF THE BRIDGE, A READ-OUT BALANCING RESISTANCE CONNECTED INTO THE BALANCING LEG OF SAID BRIDGE, AND MEANS FOR CONNECTING A RESISTANCE TO BE MEASURED INTO THE UNKNOWN LEG OF SAID BRIDEG.