Switching circuits utilizing opposite conductivity transistors

Claim 1

A BISTABLE CIRCUIT RESPONSIVE TO A SIGNAL SOURCE COMPRISING A PAIR OF TERMINALS ADAPTED TO BE CONNECTED TO A D.C. SOURCE, A PAIR OF OPPOSITE CONDUCTIVITY TYPE, NORMALLY CUT-OFF TRANSISOTRS, THE EMITTER COLLECTOR PATH OF ONE OF SAID TRANSISTORS BEING CONNECTED IN SERIES CIRCUIT BETWEEN SAID TERMINALS, SAID SERIES CIRCUIT FURTHER INCLUDING A DIODE POLED IN THE DIRECTION OF CURRENT FLOW THROUGH THE EMITTER AND COLLECTOR OF SAID FIRST TRANSISTOR, THE EMITTER BASE JUNCTION OF SAID SECOND TRANSISTOR BEING CONNECTED IN A D.C. SHUNT CIRCUIT ACROSS SAID DIODE, SAID JUNCTION AND DIODE BEING CONNECTED TO EACH OTHER TO BE FORWARD BIASED SIMULTANEOUSLY IN RESPONSE TO THE VOLTAGE ACROSS THEM, A D.C. PATH CONNECTING THE COLLECTOR OF SAID SECOND TRANSISTOR TO THE BASE OF SAID FIRST TRANSISTOR FOR COUPLING EMITTER COLLECTOR CURRENT OF THE SECOND TRANSISTOR TO THE BASE OF THE FIRST TRANSISTOR, AND MEANS COUPLING SAID SIGNAL SOURCE TO AN ELECTRODE OF ONE OF SAID TRANSISTORS TO CHANGE THE CONDUCTING STATE OF BOTH SAID TRANSISTORS IN A LIKE MANNER IN RESPONSE TO SAID SOURCE ATTAINING A PREDETERMINED AMPLITUDE, WHEREIN THE KNEES OF THE CHARACTERISTIC CURVES OF SAID DIODE AND JUNCTION ARE AT SUBSTANTIALLY THE SAME VOLTAGE SO THAT SUBSTANTIAL CONDUCTION THROUGH SAID TRANSISTOR IS CONTROLLED BY AND OCCURS SIMULTANEOUSLY WITH SAID DIODE BEING DRIVEN TO THE KNEE OF ITS CHARACTERISTIC CURVE, THE VOLTAGE OF SAID KNEES BEING DIFFERENT FROM ZERO.