H04M 3 - Automatic or semi-automatic exchanges

Patents for H04M 3 - Automatic or semi-automatic exchanges (99,881)
12/1987
12/16/1987	CN86103894A Crossbar semi-automatic telephone subscriber exchanger
12/15/1987	CA1230434A1 Key telephone system
12/15/1987	CA1230401A1 Digital peripheral switchboard for interconnecting subscribers
12/09/1987	EP0248319A1 Circuit for protecting an electronic subscriber line interface circuit
12/08/1987	US4712233 Monolithic telephone subscriber line interface circuit
12/08/1987	US4712231 Teleconference system
12/08/1987	US4712230 Monitoring and recording apparatus for connection to a telephone line
12/08/1987	CA1230162A1 Data transmission system
12/02/1987	EP0247963A2 Method for the supervision of the function of telecommunication exchanges, especially industrial telephone exchanges with party lines
12/02/1987	EP0247118A1 Interface circuit.
12/02/1987	CN87101838A Operating method of multiprocessor central control unit in high-efficiency fail-safe for exchange system
12/01/1987	US4710952 Distributed control type electronic switching system
12/01/1987	US4710951 Facsimile system
12/01/1987	US4710949 Telephone line fault locating device
12/01/1987	US4710929 Modem use monitor
12/01/1987	US4710917 Video conferencing network
12/01/1987	CA1229938A1 Teleconference system
11/1987
11/25/1987	CN87204098U Crossbar automatic instruction telephone system
11/24/1987	US4709386 Subscriber line monitoring circuit
11/24/1987	US4709296 Protection arrangement for a telephone subscriber line interface circuit
11/24/1987	US4709154 Opto-electrical signal converter with stabilization
11/19/1987	WO1987007104A1 Apparatus in a telecommunication system for supplying power to a telephone set
11/19/1987	EP0245899A1 Device for testing the line equipment of a switching exchange
11/19/1987	DE3616488A1 Subscriber circuit for a domestic telephone system
11/17/1987	US4707851 For a telephone line
11/17/1987	US4707848 Test set communication/interface system
11/17/1987	US4707831 Packet switching system
11/17/1987	US4707826 Circuit and packet data transmission system
11/17/1987	CA1229385A1 Method and apparatus for subscription broadcast
11/12/1987	DE3615183A1 Method for manual or automatic connection of an ancillary device to digital telephone stations
11/11/1987	EP0245178A1 Surveillance method to anticipate the triggering of an alarm
11/11/1987	EP0245028A2 Automated operator assistance calls with voice processing
11/11/1987	EP0245025A2 Response system of a terminal to an incoming call
11/11/1987	EP0151117B1 Method and apparatus for providing a plurality of special services
11/11/1987	EP0150183B1 Method and apparatus for providing call tracing service
11/10/1987	US4706278 Interface circuit for transmitting keycodes to a CENTREX
11/10/1987	US4706277 Interface circuit for transmitting command codes to an attendant console
11/10/1987	US4706272 Paging communication system
11/10/1987	US4706270 Equipment for sending digitally pre-stored voice announcements to the subscribers connected to a telephone network
11/07/1987	CN86201330U Automatic dialing device of telephone
11/05/1987	DE3703683C1 Method for suppressing acoustic feedback in video conference systems and circuit arrangement for carrying out the method
11/04/1987	EP0244037A1 System for transmitting and/or switching signals
11/03/1987	US4704724 Routing of network traffic
11/03/1987	CA1228946A1 Announcement system
10/1987
10/28/1987	EP0242770A2 Method for realizing different processes in a digital telecommunication terminal adapted to speech and data transmission
10/28/1987	EP0242571A2 Circuit arrangement for the connection of junction lines of a digital time division multiplex telephone network
10/28/1987	EP0242563A2 Protection circuit for the overvoltage protection of a subscriber circuit
10/28/1987	EP0242562A2 Protection circuit for the overvoltage protection of a subscriber circuit
10/27/1987	US4703499 Distributed privacy oriented telephone extension system
10/27/1987	US4703497 Four pair cable test set
10/27/1987	US4703477 Packet information field data format
10/27/1987	CA1228660A1 High capacity spatial connecting network for digital signals
10/27/1987	CA1228659A1 Method for customer definable telephone capability
10/27/1987	CA1228642A1 Electrical systems comprising temperature sensitive devices
10/22/1987	WO1987006421A1 Telephone exchange with calling telephone identification
10/20/1987	US4701950 Telephone answering system with line detector
10/20/1987	US4701699 Telephone station testing apparatus
10/14/1987	EP0241381A1 Compression method of an information set
10/14/1987	EP0241152A2 Automatic telecommunication switching system
10/13/1987	US4700380 Solid state remote actuable switch
10/13/1987	CA1228185A1 Subscriber's line closing circuit
10/13/1987	CA1228184A1 Centerpoint automatic meter reading system
10/13/1987	CA1228146A1 Multimode data communication system
10/08/1987	DE3628022A1 Testing of echo blocks in TDM telecommunication system - using decentralised process-controller assembling test bit patterns and check output relation to pattern
10/08/1987	DE3609979A1 Device for monitoring telephone terminals for faults, in particular short circuit
10/07/1987	EP0240211A2 Switching network
10/07/1987	EP0239809A2 Audio frequency signal identification apparatus
10/06/1987	US4698618 Keyboard with arrays of function keys
10/06/1987	CA1227856A1 Exchange switch
10/06/1987	CA1227835A1 Paging communication system
10/06/1987	CA1227834A1 Satellite communications system for computer networks
10/01/1987	DE3610730A1 Device for a secondary PABX system
09/1987
09/30/1987	EP0239503A1 Method and installation for the supervision of communications, especially telephone communications
09/29/1987	US4697282 Telephone operator voice storage and retrieval system
09/29/1987	CA1227586A1 Call progress for a computer telephone interface
09/24/1987	WO1987005765A1 Remotely controlled telephone hold program system
09/24/1987	WO1987005764A1 Telephone dial-up vendor service
09/24/1987	WO1987005734A1 Process for differentiating speech signals from signals of noise-free or noise-affected speech pauses
09/24/1987	DE3607682A1 Series telephone system
09/23/1987	EP0238468A2 A communication system
09/23/1987	EP0238257A2 Integrated calling directory
09/23/1987	EP0238256A2 Automated message chronicling system
09/23/1987	EP0238075A1 Method to distinguish speech signals from speech pause signals affected by noise
09/23/1987	EP0238039A2 Network event identifiers
09/23/1987	EP0237834A1 Method for controlling the services to be rendered by subsystems of a processor controlled telephone exchange and apparatus for carrying out the method
09/23/1987	EP0237656A2 Telecommunication line circuit and amplifier circuit used therein
09/22/1987	US4696029 Telephone traffic load control system
09/22/1987	US4696028 PBX Intercept and caller interactive attendant bypass system
09/22/1987	US4696026 Multiplexed terminal for monitoring and controlling a plurality of remote telephone switches
09/22/1987	US4696001 Reconfigurable high-speed integrated local network
09/22/1987	US4695977 Control of real-time systems utilizing a nonprocedural language
09/22/1987	US4695916 Protector circuit
09/22/1987	CA1227295A1 Method and system for transmitting digitized voice signals as packets of bits
09/22/1987	CA1227270A1 Secretarial answering system with distributed processing
09/22/1987	CA1227269A1 Secretarial answering system
09/22/1987	CA1227268A1 Secretarial telephone station with distributed processing for use with a secretarial answering system
09/22/1987	CA1227267A1 Secretarial telephone station for use with a secretarial answering system
09/22/1987	CA1227266A1 Arrangement for subscriber line ring testing
09/22/1987	CA1227265A1 Arrangement for facilitating external loop analysis testing for a digital switching system
09/17/1987	DE3607685A1 Circuit arrangement for telecommunications switching systems, in particular telephone PABX systems designed as brokers' systems

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