H04M 9 - Arrangements for interconnection not involving centralised switching

Patents for H04M 9 - Arrangements for interconnection not involving centralised switching (8,105)
03/1987
03/03/1987	US4648110 Circuit arrangement for a voice-controlled hands-free telephone facility
02/1987
02/26/1987	WO1987001255A1 Speakerphone for radio and landline telephones
02/26/1987	DE3528973A1 Circuit arrangement for voice-controlled attenuation of two signal paths with transmission devices operating in opposite directions
02/24/1987	US4646347 Ringing signal reformatting circuit
02/24/1987	US4646296 Distributed telephone system
02/24/1987	US4646295 Frequency-division multiplex communications system having grouped transmitters and receivers
02/24/1987	US4646289 Signal multiplexing circuit
02/19/1987	DE3528192A1 Circuit arrangement for an answering machine
02/17/1987	US4644579 Shunt regulator for hands-free telephone
02/12/1987	WO1987000995A1 An intermediate amplifier for use in two-wire connections of a dial telephone network and a method for the gain control of said amplifier
02/11/1987	CN86102081A Speakerphone sensing circuit
02/10/1987	CA1217886A Electro-optic indicating device
02/03/1987	US4641337 Key telephone system with means for operatively connecting another key telephone systems
01/1987
01/29/1987	WO1987000713A1 Asynchronous addressable electronic key telephone system
01/28/1987	CN85104080A Method station and system for the transmission of messages in the form of data packets
01/20/1987	US4638124 Key telephone system with distributed control
01/15/1987	DE3525106A1 Circuit arrangement for a telephone set, in particular an intercom set
01/13/1987	US4637014 Method of inserting and removing isochronous data into a sequence of nonisochronous data characters without slot allocation on a computer network
01/13/1987	US4636586 Speakerphone with adaptive cancellation of room echoes
01/13/1987	US4636585 Telephone installations
12/1986
12/30/1986	US4633043 Apparatus for use with key telephone systems
12/30/1986	EP0205563A1 System for selectively coupling a plurality of data stations into a single communications path.
12/30/1986	CA1216050A1 Call transfer method and circuitry
12/23/1986	US4631367 Multi-line telephone system
12/23/1986	US4631365 Intercom system
12/23/1986	US4631364 Communication system having dynamically assigned station set buttons
12/23/1986	CA1215796A1 Speakerphone linear comparator
12/16/1986	US4629832 Communication system administration method and circuitry
12/16/1986	US4629829 Full duplex speakerphone for radio and landline telephones
12/10/1986	EP0204632A1 Communication system, especially for use in an armoured vehicle
12/09/1986	US4628153 Stand-alone keyphone system
12/09/1986	CA1215187A1 Handsfree circuit for telephone instrument
12/09/1986	CA1215159A1 Programmable cartridge telephone communication system
11/1986
11/19/1986	CN86101885A Speakerphone control circuit having low gain states and method for controlling gain of speakerphone
11/19/1986	CN85109020A Full duplex speakerphone for radio and landline telephones
11/19/1986	CN85103986A Station interface of digital electronic telephone switch system having voice frequency data concentrating processor
11/06/1986	WO1986006570A1 Single line telephone communication system
11/05/1986	CN85108662A Digital loudspeaking telepnone
10/1986
10/29/1986	EP0199627A1 Circuit for the suppression of the Larsen effect in the false call zone for a subscriber telephone set
10/29/1986	CN86102953A Key telephone system
10/14/1986	CA1212737A1 Method for adjusting channel insertion timing
09/1986
09/24/1986	EP0195635A2 Key telephone system
09/23/1986	US4613904 Television monitoring device
09/09/1986	CA1211239A1 Terminal interface connecting terminal unit having central office line interface to key telephone system
09/03/1986	EP0193469A2 Method and device for the control of a hands-free telephone set with alternating operation
09/03/1986	EP0193190A2 Optical-information transmission system in the subscriber region
09/02/1986	CA1210879A1 Telecommunications system
08/1986
08/27/1986	EP0192107A2 Call-handling or information position for a telephone exchange, especially a multiple operator's position exchange
08/26/1986	US4608686 Two wire voice and data subscriber loop
08/26/1986	US4608462 Telephone instrument circuit
08/26/1986	CA1210541A1 Conferencing system adaptive signal conditioner
08/19/1986	US4607144 Apparatus for enhancing the use of electromechanical key telephone systems
08/19/1986	CA1210174A1 Handsfree communication apparatus and method
08/12/1986	US4605825 Function key assignments in a key telephone system
08/12/1986	US4605823 Phone conference system
07/1986
07/30/1986	EP0188676A2 Method for the multiple use of direct call keys at terminals, especially at operation positions in telephone exchanges, especially multiple operator's position exchanges
07/29/1986	CA1208823A1 Communication system
07/22/1986	US4602132 Key telephone system
07/22/1986	US4602128 Automatic redialing arrangement for multi-line telephone station sets
07/17/1986	WO1986004195A1 System for selectively coupling a plurality of data stations into a single communications path
07/16/1986	EP0187696A2 Full duplex conferencing system
07/15/1986	US4601064 Communication system
07/15/1986	US4600815 Automatic gain control for echo cancellers and similar adaptive systems
07/15/1986	CA1207928A1 Speakerphone control circuit
07/03/1986	WO1986003912A1 Full duplex speakerphone for radio and landline telephones
07/02/1986	CA1207030A Communication set and method
07/01/1986	US4598397 Microtelephone controller
06/1986
06/24/1986	US4597077 Integrated voice/data/control switching system
06/24/1986	CA1206653A1 Phone conference system
06/17/1986	US4595800 Key telephone system
06/17/1986	CA1206283A1 Subscriber telephone system
06/11/1986	EP0137806A4 Speakerphone control circuit.
06/05/1986	WO1986003359A1 Automatic redialing arrangement for multi-line telephone station sets
05/1986
05/28/1986	EP0182707A1 Digital telephone and data transmission system
05/27/1986	US4591670 Echo canceller and echo suppressor for frequency divisional attenuation of acoustic echoes
05/20/1986	US4590331 Hostage negotiation telephone system
05/13/1986	US4588986 Method of digitizing audio signals
05/13/1986	US4588865 Music on hold for key systems
05/13/1986	US4588864 Small key telephone system
05/13/1986	US4588861 Telephone intercom system
05/13/1986	US4588859 Two channel audio communication system
05/13/1986	CA1204489A1 Voice switching arrangement for telephone conferencing
05/06/1986	US4587651 Distributed variable bandwidth switch for voice, data, and image communications
05/06/1986	CA1204238A1 Digital echo canceller for cancelling an echo signal in a frequency divisional manner
04/1986
04/29/1986	US4585908 Data entry and display control circuit
04/15/1986	US4583221 Synchronization system for key telephone system
04/15/1986	US4583214 Key telephone transmission system
04/09/1986	EP0177465A2 Method and apparatus for operating on companded PCM voice data
04/02/1986	EP0176291A2 Key telephone system with distributed control
04/01/1986	US4580013 Handsfree communication apparatus and method
03/1986
03/26/1986	EP0174947A1 Communication system having dynamically assigned station set buttons
03/25/1986	US4578540 Telecommunications systems
03/11/1986	US4575843 Time-division-multiplexing loop telecommunication system having a first and second transmission line
03/05/1986	EP0173364A1 Method, station and system for the transmission of messages in the form of data packets
02/1986
02/25/1986	US4572928 Key telephone system
02/18/1986	US4571461 Conference telephone apparatus
02/18/1986	CA1200928A1 Broad band network system
02/11/1986	US4570035 Programmable key telephone system
02/04/1986	US4569046 Method of, and a terminal for, transmitting bytes to a bus
01/1986
01/29/1986	EP0169791A2 Music on hold for key systems and pabx systems

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