Voice-data multiplexing system for transmitting data during pauses in the voice signals

Claim 1

A VOICE-DATA MULTIPLEXING SYSTEM IN WHICH VOICE SIGNALS FROM A VOICE SOURCE AND DATA SIGNALS FROM A DATA SOURCE ARE TIME MULTIPLEXED OVER A COMMON TRANSMISSION CHANNEL, AS A COMPOSITE VOICE DATA SIGNAL, COMPRISING: TRANSMITTER MEANS, INCLUDING A VOICE SOURCE AND A DATA SOURCE; MEANS FOR NORMALLY INHIBITING SAID DATA SOURCE UNTIL IDLE GAPS IN SAID VOICE SIGNALS EXCEED A PREDETERMINED FIRST DURATION; MEANS RESPONSIVE TO THE PRESENCE OF VOICE SIGNALS FOR PRE-EMPTING ANY TRANSMISSION OF DATA FROM SAID DATA SOURCE, SAID MEANS INCLUDING MEANS FOR RESUMING THE TRANSMISSION OF VOICE SIGNALS A PREDETEMINED SECOND DURATION AFTER THE APPEARANCE OF SAID VOICE SIGNALS, WHEREBY EACH VOICE SIGNAL TRANSMITTED OVER THE COMMON TRANSMISSION CHANNEL IS PRECEDED BY A TIME INTERVAL EQUAL TO SAID SECOND DURATION; MEANS INCLUDED IN SAID DATA SOURCE FOR GENERATING AND TRANSMITTING A KEYING SIGNAL TO HERALD SUBSEQUENT DATA TRANSMISSION; RECEIVER MEANS, CONNECTED TO A DATA SINK AND A VOICE SINK, FOR RECEIVING THE COMPOSITE DATA AND VOICE SIGNAL TRANSMITTED OVER SAID COMMON TRANSMISSION CHANNEL, SAID RECEIVER MEANS HAVING TWO STATES, A DATA STATE FOR PASSING RECEIVED DATA SIGNALS TO SAID DATA SINK AND A VOICE STATE FOR PASSING RECEIVED VOICE SIGNALS TO SAID VOICE SINK; A FIRST GAP DETECTOR RESPONSIVE TO GAPS OF SAID PREDETERMINED SECOND DURATION IN SAID COMPOSITE DATAVOICE SIGNAL FOR SWITCHING SAID RECEIVER MEANS TO SAID VOICE STATE; A SECOND GAP DETECTOR RESPONSIVE TO GAPS IN SAID VOICEDATA SIGNALS WHICH EQUAL SAID PREDETERMINED FIRST DURATION, FOR INHIBITING SAID RECEIVER MEANS FROM PASSING ANY SIGNALS TO SAID VOICE SINK; AND MEANS RESPONSIVE TO SAID KEYING SIGNAL HERALDING THE RECEIPT OF DATA SIGNALS FOR SWITCHING SAID RECEIVER TO A DATA STATE, WHEREBY ANY DATA SIGNALS RECEIVED ARE PASSED TO SAID DATA SINK.