H04M 9 - Arrangements for interconnection not involving centralised switching

Patents for H04M 9 - Arrangements for interconnection not involving centralised switching (8,105)
03/1988
03/15/1988	US4731831 Telephone instrument
03/15/1988	US4731821 Single wire telephone intercommunication system
03/15/1988	CA1234235A1 Full duplex speakerphone for radio and landline telephones
03/10/1988	WO1988001821A1 Telephone configuration of the hands-free type for teleconferences
03/09/1988	EP0259218A2 Circuit arrangement for providing isolation between the transmission paths of a hands-free subset
03/08/1988	CA1233925A1 Digital loudspeaking telephone
03/01/1988	CA1233578A1 Data entry and display control circuit
02/1988
02/23/1988	US4727578 Telephone system
02/17/1988	CN87105143A Communication apparatus for building entrance
02/16/1988	US4726062 Duplex hands-free communications circuit
02/16/1988	US4726058 Telephone conversion device
02/16/1988	US4726013 Time division multiplex telecommunications system and method for a key telephone system or the like
02/16/1988	US4726010 Optical communication system in the subscriber loop
02/09/1988	US4724540 Speakerphone with fast idle mode
02/02/1988	US4723277 Loudspeaking telephone set having an anti-Larsen device for instability detection and control
02/02/1988	US4723271 Apparatus for selectively alerting party line subscribers
01/1988
01/28/1988	DE3625349A1 Circuit arrangement for call control in dual-telephone connections
01/27/1988	EP0254591A2 Teleconferencing system
01/26/1988	US4722082 ISDN subscriber terminal control system
01/21/1988	DE3623987A1 Circuit arrangement for the videotex operation in telephone branch exchanges, particularly key-type and executive-secretary systems
01/20/1988	EP0252969A1 Telephone intercom device
01/19/1988	US4720856 Control circuit having a direct current control loop for controlling the gain of an attenuator
01/12/1988	CA1231479A1 Communication system having dynamically assigned station set buttons
01/07/1988	EP0250951A2 Data communication system
12/1987
12/29/1987	CA1230949A1 Signal multiplexing circuit
12/22/1987	US4715063 Speakerphone for radio and landline telephones
12/22/1987	US4715062 Speakerphone control circuit having low gain states and method for controlling gain of speakerphone
12/22/1987	CA1230693A1 Stand-alone keyphone system
12/15/1987	CA1230437A1 Loudspeaking telephone instrument
12/15/1987	CA1230434A1 Key telephone system
12/01/1987	US4710953 Speech control in a telephone station
11/1987
11/24/1987	US4709414 Optical fiber order wire system
11/19/1987	WO1987007110A1 Hospital signaling and communications system
11/19/1987	EP0245709A1 Calling device for a building and persons including a name list
11/10/1987	US4706244 Frequency multiplexed telephone system
11/05/1987	WO1987006740A1 Method and device for transferring signals between modules of an electronic unit
11/04/1987	EP0243380A1 Distributed switching telecommunications system
10/1987
10/27/1987	US4703499 Distributed privacy oriented telephone extension system
10/27/1987	US4703416 Apparatus for locating programs resident on a cartridge of a cartridge programmable communication system
10/21/1987	EP0242030A2 Distributed telephone system
10/20/1987	US4701948 Communication system having separate unidirectional information signalling
10/15/1987	DE3611187A1 Device for switching through busbar lines of electrical assemblies which can be arranged in a row
10/13/1987	US4700382 Voice-switched telephone circuit with center idle state
10/13/1987	US4700379 Aircraft communications apparatus
09/1987
09/24/1987	DE3607682A1 Series telephone system
09/23/1987	EP0238468A2 A communication system
09/22/1987	US4696063 Optical fiber bandwidth limiting method
09/22/1987	US4696032 Voice switched gain system
09/22/1987	US4696030 Patient operator intercom arrangements for magnetic resonance imaging systems
09/16/1987	EP0236878A2 Small private telephone exchange, especially a key telephone exchange
09/16/1987	EP0236432A1 Optical fiber bandwidth limiting method.
09/15/1987	CA1226981A1 Two way telephone communication system
09/11/1987	WO1987005456A1 Device for improving the side-tone attenuation or loop amplification in interphone systems
09/10/1987	DE3706540A1 Device for improving the return loss or loop gain in intercom devices
09/09/1987	EP0235883A1 Telephone intercom device
09/09/1987	EP0235765A1 Device for improving the side-tone attenuation or the loop amplification in duplex telephone intercommunication devices
09/09/1987	EP0235529A2 Circuit arrangement for hands-free devices and devices with a receiving amplifier at telephone sets
09/01/1987	US4691348 Two way telephone communication system
09/01/1987	US4691345 Multifunction two line telephone system
08/1987
08/26/1987	EP0233518A2 Circuit for the exchange of binary signals, especially for PCM signals
08/26/1987	EP0233216A1 Speakerphone for radio and landline telephones
08/26/1987	CN87100701A Switching arrangement for communication of digital signals, in particular pcm signals
08/25/1987	US4689814 External device interface for an electronic telephone
08/25/1987	US4689506 Control circuit for use with electronic attenuators and method for providing a control signal proportional to absolute temperature
08/19/1987	EP0232315A1 Asynchronous addressable electronic key telephone system
08/12/1987	EP0231809A2 Method for integration of one or more supplementary-function modules in telephone exchanges and also access circuit for realisation of the method
08/05/1987	EP0231015A1 Coherent photonic telecommunication device
08/04/1987	US4685123 Communication system having voice and data capability
07/1987
07/21/1987	US4682353 Key telephone system
07/21/1987	US4682325 System for selectively coupling a plurality of stations into a single communications path
07/16/1987	WO1987004312A1 Telephone intercom device
07/16/1987	DE3600864A1 Circuit arrangement with means for setting the correct polarity of a telephone connection line
07/08/1987	CN86106808A Telephone set equipped for amplified listening and with an anti-larsen device
07/07/1987	US4679228 Speakerphone sensing circuit
07/07/1987	US4679191 Variable bandwidth switching system
07/01/1987	EP0227327A2 Communication systems and terminals therefor
06/1987
06/30/1987	US4677661 Microprocessor controlled telephone unit
06/25/1987	DE3544999A1 Circuit arrangement for videotex operation in telephone PBX systems, in particular intercom and executive-secretary systems
06/16/1987	EP0225714A1 Communications network
06/09/1987	US4672606 Method, station and system for the transmission of messages in the form of data packets
06/02/1987	US4670903 Echo canceller for attenuating acoustic echo signals on a frequency divisional manner
05/1987
05/26/1987	US4669108 Wireless hands-free conference telephone system
05/13/1987	EP0221090A1 Single line telephone communication system
05/12/1987	US4665545 Communication system having multi-mode line selection buttons
05/12/1987	US4665515 Digital telephone system
05/05/1987	CA1221482A1 Telephone instruments
04/1987
04/28/1987	EP0127656A4 A telephone switching arrangement.
04/28/1987	EP0126768A4 A memory cartridge for connection to a telephone switching arrangement.
04/21/1987	US4660219 Extension ringing arrangement key telephone system
04/14/1987	US4658425 Microphone actuation control system suitable for teleconference systems
03/1987
03/31/1987	US4654870 Telephone key systems and key stations therefor
03/24/1987	US4653090 Terminal for use with a communication system
03/18/1987	EP0214810A2 Radio telephone system control apparatus
03/18/1987	EP0214472A2 Control circuit for use with electronic attenuators and method for providing a control signal proportional to absolute temperature
03/17/1987	US4650932 Key telephone system
03/17/1987	CA1219325A1 Electronic key telephone system
03/12/1987	WO1987001541A1 Distributed switching telecommunications system
03/12/1987	WO1987001539A1 Optical fiber bandwidth limiting method
03/11/1987	EP0213679A1 Telephone set with a receiving amplifier provided with an anti-Larsen arrangement
03/10/1987	CA1219092A1 Time-division-multiplex loop telecommunication system comprising a first and a second transmission line

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