Transistor amplifier having protective circuitry

Claim 1

A POWER AMPLIFIER COMPRISING A PAIR OF TRANSISTORS EACH HAVING AN INPUT ELECTRODE, OUTPUT ELECTRODE, AND THIRD ELECTRODE AND BEING COUPLED TOGETHER IN A SINGLEENDED PUSH-PULL CONFIGURATION, MEANS FOR COUPLING AN INPUT VOLTAGE SIGNAL TO THE INPUT ELECTRODES OF SAID TRANSISTORS TO SELECTIVELY PLACE EACH OF SAID TRANSISTORS IN A CONDUCTIVE STATE, OUTPUT TRANSFORMER MEANS INCLUDING A FIRST PRIMARY WINDING COUPLED TO EACH OF SAID OUTPUT ELECTRODES OF SAID TRANSISTOR DEVICES, SAID OUTPUT TRANSFORMER PROVIDING A SIGNAL TO A UTILIZATION DEVICE IN RESPONSE TO SAID INPUT SIGNAL, AND A PROTECTIVE CIRCUIT MEANS PROVIDING A SIGNAL TO EACH INPUT ELECTRODE OF SAID PAIR OF TRANSISTORS TO BLOCK CONDUCTION OF SAID TRANSISTORS WHENEVER THE OUTPUT VOLTAGE PROVIDED BY EACH OF SAID PAIR OF TRANSISTORS REVERSES WHILE SAID INPUT VOLTAGE HAS NOT YET REVERSED INCLUDING SECOND AND THIRD PRIMARY WINDINGS OF SAID TRANSFORMER EACH COUPLING THE INPUT ELECTRODE OF ONE OF SAID TRANSISTORS TO SAID FIRST PRIMARY WINDING FOR APPLYING A SIGNAL TO SAID INPUT ELECTRODE PROPORTIONAL TO SAID SIGNAL PROVIDED TO SAID UTILIZATION DEVICE.