Signal level control apparatus

Claim 1

SIGNAL LEVEL CONTROL APPARATUS COMPRISING, IN COMBINATION: A SOURCE OF AN INPUT SIGNAL INCLUDING PERIODICALLY RECURRENT REFERENCE LEVEL PORTIONS; AN INPUT TERMINAL; CIRCUIT MEANS CONNECTING SAID INPUT SIGNAL TO SAID INPUT TERMINAL; AN OUTPUT TERMINAL; A COUPLING CIRCUIT COUPLING SAID INPUT TERMINAL TO SAID OUTPUT TERMINAL, SAID COUPLING CIRCUIT INCLUDING A SERIES COUPLING CAPACITOR; DRIVE PULSE GENERATOR MEANS PRODUCING PULSERS OCCURRING DURING SAID RECURRENT SIGNAL PORTIONS; CONTROL PULSE GENERATOR MEANS RESPONSIVE TO A CONTROL SIGNAL AND TO DRIVE PULSES TO DEVELOP FIRST AND SECOND CONTROL PULSES OF LIKE POLARITY, THE AMPLITUDES OF SAID FIRST AND SECOND CONTROL PULSERS VARYING OPPOSITELY WHEN THE AMPLITUDE OF SAID CONTROL SIGNAL DURING SAID DRIVE PULSES HAS A VALUE DIFFERING FROM A PREDETERMINED VALUE; MEANS FOR APPLYING SAID INPUT SIGNAL TO SAID CONTROL PULSE GENERATOR; MEANS FOR APPLYING SAID DRIVE PULSES TO SAID CONTROL PULSE GENERATOR; A STORAGE CAPACITOR HAVING FIRST AND SECOND TERMINALS; A POINT OF CONSTANT POTENTIAL; A DIRECT CONNECTION FROM SAID SECOND TERMINAL OF SAID STORAGE CAPACITOR TO SAID POINT OF CONSTANT POTENTIAL; A DIRECT CURRENT SOURCE HAVING FIRST AND SECOND POLES; FIRST PULSE CONTROLLED CURRENT VARYING MEANS CONNECTED TO CONTROL THE FLOW OF CURRENT FROM SAID SOURCE TO SAID FIRST TERMINAL OF SAID STORAGE CAPACITOR; SECOND PULSE CONTROLLED CURRENT VARYING MEANS CONNECTED TO CONTROL THE FLOW OF CURRENT FROM SAID FIRST TERMINAL OF SAID STORAGE CAPACITOR TO SAID SECOND POLE OF SAID CURRENT SOURCE; MEANS FOR APPLYING SAID FIRST AND SECOND CONTROL PULSES TO CONTROL SAID FIRST AND SECOND CURRENT VARYING MEANS RESPECTIVELY; AND CIRCUIT MEANS FOR APPLYING THE POTENTIAL APPEARING AT SAID FIRST TERMIAL OF SAID STORAGE CAPACITOR TO CONTROL THE POTENTIAL OF A POINT IN SAID COUPLING CIRCUIT SUBSEQUENT TO SAID COUPLING CAPACITOR.