Power amplifier employing pulse duration modulation

Claim 1

A POWER AMPLIFIER CIRCUIT COMPRISING: A LOAD; A SOURCE OF UNIDIRECTLY ELECTRICAL ENERGY; A FIRST PAIR OF TRANSISTORS HAVING INPUT AND OUTPUT ELECTRODES, THE OUTPUT ELECTRODES THEREOF BEING CONNECTED IN SERIES WITH THE SOURCE AND THE LOAD AND AN OPPOSITE SIDES OF THE LOAD TO DEFINE A FIRST ENERGY PATH THROUGH THE LOAD WHEN CONDUCTIVE; A SECONE PAIR OF TRANSISTORS HAVING INPUT AND OUTPUT ELECTRODES, THE OUTPUT ELECTRODES THEREOF BEING CONNECTED IN SERIES WITH THE SOURCE AND THE LOAD AND A OPPOSITE SIDES OF THE LOAD TO DEFINE, WHEN CONDUCTIVE, A SECOND ENERGY PATH THROUGH THE LOAD OPPOSITE IN DIRECTION TO THE FIRST PATH; MEANS NORMALLY MAINTAINING SELECTED ONES OF THE FIRST AND SECOND TRANSISTOR PAIRS WHICH ARE ON OPPOSITE SIDES OF THE LOAD IN A CONDUCTIVE STATE THEREBY TO SHORT OUT THE LOAD; MEANS NORMALLY MAINTAINING THE REMAINING TRANSISTORS IN A NONCONDUCTIVE STATE; FIRST CONTROL MEANS CONNECTED TO THE INPUT ELECTRODE OF ONE TRANSISTOR IN EACH PAIR WHICH TRANSISTORS ARE OPPOSITE NORMAL CONDUCTIVITY, THE CONTROL MEANS BEING RESPONSIVE TO SIGNALS OF A FIRST CHARACTER TO REVERSE THE CONDUCTIVITY OF THE TRANSISTORS CONNECTED THEREWITH TO COMPLETE SAID FIRST ENERGY PATH; SECOND CONTROL MEANS CONNECTED TO THE INPUT ELECTRODES OF THE OTHER TRANSISTOR IN EACH PAIR OF RESPONSIVE TO SIGNALS OF A SECOND CHARACTER TO REVERSE THE CONDUCTIVITY OF THE TRANSSISTORS THEREBY TO COMPLETE THE SECOND ENERGY PATH; AND MEANS FOR ALTERNATELY PROVIDING SIGNALS OF SAID FIRST AND SECOND CHARACTER TO THE FIRST AND SECOND CONTROL MEANS RESPECTIVELY, FOR DURATIONS WHICH ARE RELATED TO A PRESELECTED VARIABLE.