Transistor testing apparatus for measuring the beta, leakage and cutoff current parameters

Claim 1

APPARATUS FOR MEASURING THE CUTOFF CURRENT FOR A PARTICULAR COLLECTOR VOLTAGE OF A TRANSISTOR, IN SITU, SAID TRANSISTOR INCLUDING EMITTER, COLLECTOR AND BASE TERMINALS, A DEENERGIZED SOURCE OF OPERATING POTENTIALS INCLUDING OUTPUT TERMINALS AND COUPLING MEANS FOR COUPLING THE OUTPUT TERMINALS OF SAID SOURCE OF OPERATING POTENTIALS TO THE TERMINALS OF SAID TRANSISTOR, SAID APPARATUS COMPRISING A REFERENCE POTENTIALS MEANS, MEANS FOR CONNECTING THE OUTPUT TERMINALS OF SAID SOURCE OF OPERATING POTENTIALS TO SAID REFERENCE POTENTIAL MEANS, MEANS FOR APPLYING A DIRECTCURRENT VOLTAGE EQUAL TO THE PARTICULAR COLLECTOR VOLTAGE WITH RESPECT TO SAID REFERENCE POTENTIAL MEANS DIRECTLY TO SAID COLLECTOR, IMPEDANCE MEANS FOR CONNECTING SAID BASE, EMITTER AND COLLECTOR TERMINALS RESPECTIVELY TO SAID REFERENCE POTENTIAL MEANS, MEANS FOR GENERATING A DIRECT-CURRENT ERROR SIGNAL PROPORTIONAL TO THE DIFFERENCE IN THE DIRECT-CURRENT VOLTAGE OF SAID BASE AND SAID REFERENCE POTENTIAL MEANS VOLTAGE, A DIRECT-CURRENT AMMETER HAVING FIRST AND SECOND TERMINALS, MEANS FOR CONNECTING SAID FIRST TERMINAL TO SAID ERROR SIGNAL GENERATING MEANS AND SAID SECOND TERMINAL TO SAID BASE WHEREBY THE DIRECT CURRENT MEASURED BY SAID DIRECT-CURRENT AMMETER INDICATES THE CUTOFF CURRENT.