Transistor power amplifiers

Claim 1

A TRANSISTOR POWER AMPLIFIER COMPRISING A PUSH-PULL POWER OUTPUT STAGE INCLUDING A GROUND TERMINAL AND AN OUTPUT TERMINAL HAVING A RELATIVELY LOW OUTPUT IMPEDANCE, A STAGE PRECEDING SAID OUTPUT STAGE AND INCLUDING AT LEAST TWO TRANSISTORS EACH HAVING A BASE, ONE OF SAID TRANSISTORS HAVING AN EMITTER AND THE OTHER OF SAID TRANSISTORS HAVING A COLLECTOR, SAID TRANSISTOR BEING CONNECTED IN SERIES WITH THE EMITTER OF SAID ONE TRANSISTOR CONNECTED TO THE COLLECTOR OF THE OTHER TRANSISTOR AND HAVING A TOTAL VOLTAGE THEREACROSS VARYING COEXTENSIVELY WITH SAID OUTPUT TERMINAL, MEANS FOR CONNECTING A SIGNAL SOURCE TO ONE OF SAID BASES, MEANS TRANSMITTING THE OUTPUT SIGNAL OF SAID PRECEDING STAGE TO SAID OUTPUT STAGE TO DRIVE THE LATTER, AND CIRCUIT MEANS CONNECTING SAID OUTPUT TERMINAL TO THE OTHER BASE TO DRIVE THE LATTER SO AS TO PROVIDE APPROXIMATELY EQUAL VOLTAGE SWINGS OF SAID TRANSISTORS IN RESPONSE TO A SIGNAL SOURCE APPLIED TO SAID ONE BASE.