Automatic gain control circuit using plural time constant means

Claim 1

IN A CIRCUIT FOR PRODUCING AN AUTOMATIC GAIN CONTROL VOLTAGE, A SOURCE OF INTERMITTENT SIGNALS CONVEYING INFORMATION, A FIRST STORAGE ELEMENT, MEANS FOR CHARGING SAID FIRST STORAGE ELEMENT TO A DIRECT-CURRENT VOLTAGE INDICATIVE OF THE LEVEL OF SAID SIGNAL, A CONDITIONAL DISCHARGE PATH FOR SAID FIRST STORAGE ELEMENT, A SECOND STORAGE ELEMENT HAVING A PERMANENT DISCHARGE PATH, MEANS FOR CHARGING SAID SECOND STORAGE ELEMENT TO A VOLTAGE INDICATIVE OF THE LEVEL OF SAID SIGNAL AND LARGER THAN THE VOLTAGE TO WHICH SAID FIRST ELEMENT IS CHARGED, MEANS ACTUATED BY THE SUM OF THE VOLTAGE ACROSS SAID SECOND STORAGE ELEMENT AND SAID SIGNAL VOLTAGE DURING PERIODS WHEN SAID SUM VOLTAGE ASSUMES A PREDETERMINED VALUE RELATIVE TO THE POTENTIAL ACROSS SAID FIRST STORAGE ELEMENT FOR COMPLETING SAID CONDITIONAL DISCHARGE PATH, AND AN AUTOMATIC GAIN CONTROL OUTPUT CIRCUIT CONNECTED ACROSS SAID FIRST STORAGE ELEMENT.