Method and apparatus for increasing the readability of amplitude modulated waves

Claim 1

APPARATUS FOR INCREASING THE READABILITY OF AN AMPLITUDE MODULATED SIGNAL HAVING AT LEAST A PAIR OF SIDE BAND SIGNALS AS COMPONENTS THEREOF, SAID APPARATUS COMPRISING: FIRST FILTER MEANS RESPONSIVE TO SAID AMPLITUDE MODULATED SIGNAL AND ADAPTED TO HAVE THE SAME APPLIED THERETO FOR ATTENUATING THE COMPONENTS OF SAID AMPLITUDE MODULATED SIGNAL EXCEPT ONE OF SAID SIDE BAND SIGNALS; SECOND FILTER MEANS RESPONSIVE TO SAID AMPLITUDE MODULATED SIGNAL AND ADAPTED TO HAVE THE SAME APPLIED THERETO FOR ATTENUATING THE COMPONENTS OF SAID AMPLITUDE MODULATED SIGNAL EXCEPT THE OTHER SIDE BAND SIGNAL; MEANS FOR PROVIDING A CARRIER SIGNAL FOR SAID SIDE BAND SIGNALS; FIRST ELECTRICAL MEANS COUPLED WITH SAID FIRST FILTER MEANS AND SAID CARRIER PROVIDING MEANS FOR SUBSTRACTING THE FREQUENCY OF THE LOWER OF SAID ONE SIDE BAND AND CARRIER SIGNALS FROM THE FREQUENCY OF THE HIGHER THEREOF TO PRODUCE A FIRST INTELLIGENCE SIGNAL; SECOND ELECTRICAL MEANS COUPLED WITH SAID SECOND FILTER MEANS AND SAID CARRIER PROVIDING MEANS FOR SUBTRACTING THE FREQUENCY OF THE LOWER OF SAID OTHER SIDE BAND AND CARRIER SIGNALS FROM THE FREQUENCY OF THE HIGHER THEREOF TO PRODUCE A SECOND INTELLIGENCE SIGNAL, SAID CARRIER PROVIDING MEANS COMPRISING AN OSCILLATOR STAGE FOR LOCALLY GENERATING SAID CARRIER SIGNAL AND DISCRIMINATOR MEANS COUPLED WITH SAID STAGE AND RESPONSIVE TO SAID FIRST AND SECOND INTELLIGENCE SIGNALS FOR CONTROLLING THE PHASE OF SAID GENERATED CARRIER SIGNAL TO MAINTAIN SAID FIRST INTELLIGENCE SIGNAL IN PHASE WITH SAID SECOND INTELLIGENCE SIGNAL; TRANSDUCER MEANS COUPLED WITH SAID FIRST ELECTRICAL MEANS AND RESPONSIVE TO SAID FIRST INTELLIGENCE SIGNAL FOR CONVERTING THE LATTER INTO A FIRST SOUND WAVE; AND PHASE REVERSAL MEANS COUPLED WITH SAID SECOND ELECTRICAL MEANS AND RESPONSIVE TO SAID SECOND INTELLIGENCE SIGNAL FOR CONVERTING THE LATTER INTO A SECOND SOUND WAVE SUBSTANTIALLY 180 DEGREES OUT-OF-PHASE WITH SAID FIRST SOUND WAVE.