Patents
Sitemap › H04 - Electric communication technique › H04M - Telephonic communication › H04M 3 - Automatic or semi-automatic exchanges
Patents for H04M 3 - Automatic or semi-automatic exchanges (99,881)
06/1990
06/27/1990CN1043417A Telephone protection circuit
06/27/1990CN1043416A System for connecting optical lines to wideband telecommunications exchange
06/27/1990CN1008594B Digital timeslot and signaling bus in digital pbx switch
06/26/1990US4937862 Remote monitoring device
06/26/1990US4937856 Digital voice conferencing bridge
06/26/1990US4937851 Loop status verification system
06/26/1990US4937850 Programmable automatic call-thru set
06/26/1990US4937464 Modular jack with loop testing switch
06/21/1990DE3842879A1 Method and arrangement for storing voice data in a telephone PBX system
06/19/1990US4935959 Two-wire telecommunications line detection arrangements
06/19/1990US4935958 Busy/no-answer call completion equipment
06/19/1990US4935957 Key telephone system
06/19/1990US4935954 Automated message retrieval system
06/14/1990WO1990006650A1 Watching method based on telephone system
06/13/1990EP0372673A2 Telephone protection circuit
06/13/1990EP0372446A1 Device for connecting optical lines with a broadband telecommunication exchange
06/13/1990EP0214215B1 Arrangement for accessing and testing telecommunication circuits
06/13/1990EP0214178B1 Controlling multi-port hunt groups in a distributed control switching system
06/13/1990DE3841965A1 Processor load simulation device
06/12/1990US4933967 Automatically-effected move of a subscriber between electronic message service systems in a network
06/12/1990US4933966 Method and apparatus for performing an automated collect call
06/12/1990US4933964 Pacing of telephone calls for call origination management systems
06/12/1990US4933962 Continuity test set with voice communication
06/12/1990CA1270315A1 Busy/no-answer call completion equipment
06/06/1990EP0371676A2 Communication channel reallocation
06/06/1990EP0371674A2 Communication channel reservation
06/06/1990EP0371662A2 Remote testing of metallic loops with a trans hybrid signal
06/06/1990EP0371609A2 Electronic mail systems
06/06/1990EP0371169A1 Method for controlling the taking over of, on the one hand, switching-related tasks and, on the other hand, operational and/or protection-related tasks by a processor in the central control unit of a telecommunications switching system
06/06/1990CN1042786A Parallel microcomputer of user digital terminal with digital network of centralization service
06/05/1990US4932050 Proximity detection for telecommunications features
06/05/1990US4932042 Spontaneous voice and data messaging
06/05/1990US4932021 Path learning feature for an automated telemarketing system
06/05/1990US4931941 Adaptive routing of network traffic
05/1990
05/31/1990WO1990006039A1 Communication system providing automatic identification of calling parties
05/31/1990DE3840306A1 Method for text communication between terminals, in particular telephone terminals, connected to communications switching systems
05/31/1990DE3839627A1 Telephone terminal
05/30/1990EP0370662A2 Password controlled switching system
05/30/1990EP0370423A2 Device for forming an interchange point in a telecommunications network
05/30/1990EP0222828B1 Agent communication method for telecommunication systems
05/29/1990US4930154 Audible logo for identifying a common carrier
05/29/1990US4930153 PBX voice mail interface
05/29/1990US4930152 Call return telephone service
05/29/1990US4930151 Telephone call forwarding device
05/29/1990US4930150 Telephonic interface control system
05/23/1990CN2057541U Line-concentrating volume-enlarging telephone exchanger
05/22/1990US4928306 Dynamically configurable telephone
05/22/1990US4928304 Electronic switching system connected to an external computer
05/16/1990EP0126768B1 A memory cartridge for connection to a telephone switching arrangement
05/16/1990CN2057300U 100 line exchange for automatic telephone subscriber
05/16/1990CN1008049B Security arrangement for telecommunications exchange system
05/16/1990CN1008044B Changeover system of dispatching telephone
05/15/1990US4926471 Communication system
05/15/1990US4926470 Telephone call screening circuit
05/15/1990US4926462 Telephone system
05/15/1990US4926461 Telephone answering machine having call transfer capabilities
05/15/1990US4926363 Modular test structure for single chip digital exchange controller
05/15/1990CA1269156A1 Subscriber pair identification system
05/10/1990DE3837610A1 Method and circuit arrangement for alerting videotex subscribers to new videotex messages which they have received but not yet read
05/09/1990EP0367455A2 Phone management server for use with a personal computer lan
05/09/1990EP0366788A1 D channel monitor
05/08/1990US4924500 Carrier independent network services
05/08/1990US4924492 Method and apparatus for wideband transmission of digital signals between, for example, a telephone central office and customer premises
05/08/1990US4924491 Arrangement for obtaining information about abandoned calls
05/08/1990US4924489 Customer line tester
05/08/1990US4924488 Multiline computerized telephone monitoring system
05/08/1990US4924341 Unidirectional circuit device
05/08/1990CA1268871A1 Test set communications/interface system
05/03/1990WO1990004897A1 Telephone plant
05/02/1990EP0365905A2 Process for controlling centrally controlled communication exchanges
05/02/1990EP0365649A1 Apparatus and method for mapping the connectivity of communications systems with multiple communications paths
05/01/1990US4922538 Multi-user speech recognition system
05/01/1990US4922529 Automatic hangup apparatus for restoring service to off-hook telephones
05/01/1990US4922526 Automated access facilities for use with key telephone systems
05/01/1990US4922523 Videotex with telephone call screening system
05/01/1990US4922522 Telecommunications access to lottery systems
05/01/1990US4922520 Automatic telephone polling system
05/01/1990US4922519 Automated operator assistance calls with voice processing
05/01/1990US4922516 Telephone technician's terminals with auto-selection of dial pulse on DTMF signalling
05/01/1990US4922515 Communication network cut-off detection arrangement
05/01/1990US4922489 Circuit configuration for routine testing of the clock supply of a large number of units operated with the same clock
05/01/1990CA1268568A1 Communications network and method with appointment information communication capabilities
05/01/1990CA1268551A1 Program update in duplicated switching systems
05/01/1990CA1268546A1 Stereophonic voice signal transmission system
05/01/1990CA1268531A1 Control data transmission system for private branch exchange
04/1990
04/25/1990EP0365200A2 Telecommunication system with subscriber controlled feature modification
04/25/1990EP0364444A1 Internal communication system.
04/25/1990CN1041680A Digital switched telecommunications system
04/25/1990CN1007775B Pabx-networking
04/24/1990US4920565 Method for connection of secure conference calls
04/24/1990US4920558 Method and apparatus for downloading speech files
04/24/1990US4920556 Telephone with built-in emergency panic switch, long distance toll timer and music on hold cards
04/24/1990US4920534 System for controllably eliminating bits from packet information field based on indicator in header and amount of data in packet buffer
04/24/1990US4920529 Network control method and apparatus therefor
04/24/1990CA1268275A1 Programmable telephone/dictation terminal and method of operating same
04/24/1990CA1268273A1 Telephone call processing system
04/19/1990WO1990004298A1 Integrated telecommunication system with improved digital voice response
04/18/1990EP0364090A2 Method and apparatus for efficient resource allocation
04/17/1990US4918719 Elimination of false requests for telephone operator assistance
04/17/1990US4918322 Operator)assisted telephone service facilities
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