Circuit for varying the drive of an amplifier in accordance with power output demand

Claim 1

ELECTRONIC APPARATUS COMPRISING , A DRIVING AMPLIFIER HAVING INPUT AND OUTPUT CIRCUITS; MEANS APPLYING AN A.C. INPUT SIGNAL OF PREDETERNINED LEVEL TO THE DRIVING AMPLIFIER INPUT CIRCUIT; A D.C. SUPPLY POTENTIAL APPLIED TO THE DRIVING AMPLIFIER; A POWER AMPLIFIER HAVING AN INPUT CIRCUIT CONNECTED TO THE OUTPUT CIRCUIT OF THE DRIVING AMPLIFIER AND AN OUTPUT CIRCUIT; AN OUTPUT TRANSFROMER HAVING A PRIMARY WINDING CONNECTED IN THE POWER AMPLIFIER OUTPUT CIRCUIT, A FIRST SECONDARY WINDING CONNECTED TO THE APPARATUS OUTPUT TERMINALS AND A SECOND SECONDARY WINDING; A CURRENT TRANSFORMER HAVING A PRIMARY WINDING CONNECTED IN SERIES WITH THE SAID FIRST SECONDARY WINDING OF THE OUTPUT TRANSFORMER, A FIRST SECONDARY WINDING AND A SECOND SECONDARY WINDING; A FIRST RECTIFIER NETWORK CONNECTED ACROSS THE SAID FIRST SECOND WINDING OF THE CURRENT TRANSFORMER; CIRCUIT ELEMENTS FOR ADDING THE D.C. OUTPUT VOLTAGE OF THE FIRST RECTIFIER NETWORK TO THE SAID D.C. SUPPLY POTENTIAL; A SECOND RECTIFIER NETWORK; CIRCUIT ELEMENTS APPLYING TO THE SECOND RECTIFIER NETWORK THE COMBINED VOLTAGES DEVELOPED IN THE SECOND SECONDARY WINDINGS OF THE OUTPUT AND CURRENT TRANSFORMERS; AND MEANS REDUCING THE LEVEL OF THE SAID A.C. INPUT SIGNAL WHEN THE D.C. OUTPUT VOLTAGE OF THE SECOND RECTIFIER NETWORK EXCEEDS A PREDETERMINED VALUE.