Stereo multiplex receiver with automatic stereo or monaural detection and indicating means

Claim 1

A SYSTEM FOR PRODUCING A AND B AUDIO FREQUENCY SIGNALS FROM A COMPOSITE SIGNAL CONSTITUTED BY AN (A+B) SIGNAL, A PILOT SIGNAL, AND THE SIDEBAND FREQUENCIES OF A SUPERSONIC CARRIER OF A FREQUENCY HARMONICALLY RELATED TO SAID PILOT SIGNAL AND SUPPRESSED CARRIER AMPLITUDE MODULATED BY AN (A-B) SIGNAL, COMPRISING; MEANS FOR AMPLIFYING SAID PILOT SIGNAL AND ALTERING ITS FREQUENCY TO CORRESPOND TO THE SAID SUPERSONIC CARRIER FREQUENCY, MEANS FOR APPLYING THE PRODUCED SUPERSONIC CARRIER, THE (A+B) AND THE (A-B) SIDEBAND FREQUENCIES SIGNALS TO THE COMMON JUNCTION OF TWO UNILATERALLY CONDUCTING DEVICES CONNECTED IN SERIES SENSE, A PAIR OF SERIALLY-CONNECTED LOAD CIRCUITS CONNECTED ACROSS THE NON-COMMON TERMINALS OF SAID UNILATERALLY CONDUCTING DEVICES, MEANS CONNECTING THE COMMON JUNCTION OF THE LOAD CIRCUITS TO A SOURCE OF REFERENCE POTENTIAL, SWITCH MEANS SHUNTING SAID UNILATERALLY CONDUCTING DEVICES, AND MEANS RESPONSIVE TO THE PILOT SIGNAL FOR OPENING THE SWITCH WHEN THE PILOT SIGNAL ATTAINS A PREDETERMINED MINIMUM VALUE TO PRODUCE THE A SIGNAL ACROSS ONE OF THE LOAD CIRCUITS AND THE B SIGNAL ACROSS THE OTHER AND FOR CLOSING SAID SWITCH TO SHORT-CIRCUIT THE NONCOMMON TERMINALS OF THE SERIES AIDING UNILATERALLY CONDUCTING DEVICES WHEN THE PILOT SIGNAL FALLS BELOW A PREDETERMINED VALUE TO CONNECT BOTH CIRCUITS IN PARALLEL TO PRODUCE THE SAME SIGNAL IN EACH HALF.

Claim 2

A SYSTEM FOR PRODUCING A AND B AUDIO FREQUENCY SIGNALS FROM A COMPOSITE SIGNAL CONSTITUTED BY AN (A+B) SIGNAL, A PILOT SIGNAL, AND THE SIDEBAND FREQUENCIES OF A SUPERSONIC CARRIER OF A FREQUENCY HARMONICALLY RELATED TO SAID PILOT SIGNAL AND SUPPRESSED CARRIER AMPLITUDE MODULATED BY AN (A-B) SIGNAL, COMPRISING; MEANS FOR AMPLIFYING SAID PILOT SIGNAL AND ALTERING ITS FREQUENCY TO CORRESPOND TO THE SAID SUPERSONIC CARRIER FREQUENCY, MEANS FOR APPLYING THE PRODUCED SUPERSONIC CARRIER, THE (A+B) AND THE (A-B) SIDEBAND FREQUENCIES SIGNALS TO THE COMMON JUNCTION OF TWO UNILATERALLY CONDUCTING DEVICES CONNECTED IN SERIES SENSE, A PAIR OF SERIALLY-CONNECTED LOAD CIRCUITS CONNECTED ACROSS THE NON-COMMON TERMINALS OF SAID UNILATERALLY CONDUCTING DEVICES, MEANS CONNECTING THE COMMON JUNCTION OF THE LOAD CIRCUITS TO A SOURCE OF REFERENCE POTENTIAL, SWITCH MEANS SHUNTING SAID UNILATERALLY CONDUCTING DEVICES, AND MEANS RESPONSIVE TO THE PILOT SIGNAL FOR OPENING THE SWITCH WHEN THE PILOT SIGNAL ATTAINS A PREDETERMINED MINIMUM VALUE TO PRODUCE THE A SIGNAL ACROSS ONE OF THE LOAD CIRCUITS AND THE B SIGNAL ACROSS THE OTHER AND FOR CLOSING SAID SWITCH TO SHORT-CIRCUIT THE NONCOMMON TERMINALS OF THE SERIES AIDING UNILATERALLY CONDUCTING DEVICES WHEN THE PILOT SIGNAL FALLS BELOW A PREDETERMINED VALUE TO CONNECT BOTH CIRCUITS IN PARALLEL TO PRODUCE THE SAME SIGNAL IN EACH HALF.