Electrical amplifier with input circuit direct-current-limiting means

Claim 1

AN INTEGRATED CIRCUIT AMPLIFIER COMPRISING, IN COMBINATION, A WAFER, A PLURALITY OF TRANSISTORS INCLUDING FIRST AND SECOND SIMILAR TRANSISTORS INTEGRAL WITH SAID WAFER, A PAIR OF INPUT TERMINALS INTERGRAL WITH SAID WAFER, BIAS TERMINAL MEANS INTEGRAL WITH SAID WAFER FOR RECEIVING DIRECT CURRENT BIAS SIGNALS, MEANS FOR CONNECTING SAID BIAS TERMINAL MEANS TO SAID TRANSISTORS, AND MEANS FOR CONNECTING EACH OF SAID INPUT TERMINALS TO THE BASE TERMINAL OF A RESPECTIVE ONE OF SAID FIRST AND SECOND TRANSISTORS, AND MEANS FOR INTERCONNECTING THE COLLECTOR AND EMITTER ELECTRODES OF SAID FIRST AND SECOND TRANSISTORS FOR ESTABLISHING AND MAINTAINING THE DIRECT CURRENT POTENTIAL OF ONE OF SAID INPUT TERMINALS AT SUBSTANTIALLY THE SAME LEVEL AS THE DIRECT CURRENT POTENTIAL OF THE OTHER OF SAID INPUT TERMINALS, AND, CONNECTED TO SAID INPUT TERMINALS, A MICROPHONE WHICH WOULD BE RENDERED SUBSTANTIALLY INOPERATIVE BY THE FULL FLOW OF DIRECT CURRENT THROUGH IT.