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)
05/1987
05/27/1987EP0222828A1 Agent communication method for telecommunication systems.
05/26/1987US4669113 Integrated network controller for a dynamic nonhierarchical routing switching network
05/26/1987US4669112 Automatic telephone number indicating device
05/26/1987US4669111 Polarity ring director
05/26/1987US4669108 Wireless hands-free conference telephone system
05/20/1987EP0222357A2 Traffic data collecting arrangement comprising a template data memory in each exchange
05/20/1987EP0222304A1 Space-switching device for broad-band signals
05/20/1987EP0222251A2 A method of providing notification to a held party.
05/20/1987EP0222083A1 Method and apparatus for voice detection having adaptive sensitivity
05/20/1987CN85106918A 回音消除器 Echo canceller
05/19/1987US4667320 Space-division switching network for high data rate signals
05/13/1987EP0221519A2 Ringing application circuit
05/13/1987EP0221140A1 Operator communication arrangements for operator assistance systems
05/12/1987US4665547 Limiting amplifier for common mode feedback in telephone line feed circuits
05/12/1987CA1221756A1 System for accessing electrical circuits and relay switch thereof
05/07/1987WO1987002837A1 Telephone subscriber loop overvoltage protection integrated circuit
05/06/1987CN86107155A Wide band signal space coupling arrangements
05/05/1987US4663777 Apparatus for controlling digital voice recording and playback over telephone lines and adapted for use with standard host computers
05/05/1987US4663776 System for accessing electrical circuits and relay switch thereof
05/05/1987US4663775 Method and apparatus for testing remote communication systems
05/05/1987CA1221481A1 Hookswitch bounce resistant telephone hold-mute circuit
05/05/1987CA1221445A1 Semaphore terminal device for the nd 7 signalling system
05/05/1987CA1221444A1 Apparatus for use in an exchange of a telephone system
04/1987
04/29/1987EP0219917A2 Switching device with fault correction
04/29/1987EP0219848A2 Space switching device for broad-band signals
04/29/1987EP0219771A2 Method for influencing dial number evaluation and translation processes in a programme-controlled telecommunication switching system
04/29/1987CN85205088U Model 55 mutually controlled skip frequence carrier
04/28/1987US4661979 Fault protection for integrated subscriber line interface circuits
04/28/1987US4661975 Enhanced call-waiting service
04/28/1987US4661974 Automatic route selection of a private telephone network path on the basis of a public telephone network number
04/28/1987US4661971 Digital signal cross-connection system
04/28/1987US4661969 Communication lines with terminate and leave capability-VF data bridge
04/28/1987US4661949 Circuit for conference telephony
04/28/1987US4661878 Overvoltage protection circuit
04/28/1987EP0127656A4 A telephone switching arrangement.
04/28/1987EP0126768A4 A memory cartridge for connection to a telephone switching arrangement.
04/28/1987CA1221156A1 Data call transfer preindication
04/23/1987DE3537200A1 Circuit arrangement for identifying the loop current in telephone systems
04/22/1987EP0218904A2 Process for modifying operation of application program
04/22/1987EP0218871A2 Hardware resource management
04/22/1987EP0218862A1 Method for connecting additional telephone paths and sound signals at an existing telephone connexion between two subscribers
04/21/1987US4660220 No answer mode for telephone systems
04/21/1987US4659877 Verbal computer terminal system
04/15/1987EP0218395A2 Conference circuits and methods of operating them
04/15/1987EP0218149A2 Device and method for realizing telephone conversations between three and more subscriber sets
04/14/1987US4658425 Microphone actuation control system suitable for teleconference systems
04/14/1987US4658416 Automatic call transfer system capable of carrying out call transfer without manual operation
04/14/1987US4658398 Framed digital voice summing for teleconferencing
04/14/1987US4658395 Method for locating faults in a carrier subscriber communication system
04/14/1987US4658098 Circuit arrangement for telecommunications switching systems, particularly telephone switching systems, comprising information-processing central switch devices and sub-central switching facilities which supply the same with information
04/08/1987EP0217555A2 Telecommunication switching system
04/08/1987EP0217308A2 A method of and an arrangement for forwarding a customer order
04/08/1987EP0217130A2 Circuit arrangement for an electronic interface circuit
04/07/1987US4656660 Office line holding circuit with an automatic release function for direct connection telephone system
04/07/1987US4656659 Programmable ring signal generator
04/07/1987US4656654 Computer assisted graphic teleconferencing method and apparatus
04/07/1987US4656651 System for providing remote services
04/07/1987US4656625 Switching system having capability for telecommunication conferences
04/07/1987US4656624 Operator communication arrangements for operator assistance systems
04/07/1987US4656623 Agent communication arrangements for telecommunication systems
04/07/1987CA1220266A1 Integrated communication system
04/07/1987CA1220265A1 Method and apparatus for providing call tracing service
04/02/1987DE3534533A1 Centrally controlled PABX system
04/01/1987EP0216545A2 System for providing remote services
04/01/1987EP0216515A2 Method of and apparatus for connecting remote users of a telephone trunk interface and the like
04/01/1987EP0216381A2 Discretionary call forwarding
04/01/1987EP0216359A2 Method of preventing overloading of the central controller of a processor-controlled telephone system
03/1987
03/31/1987US4654845 Parallel call processing system and method
03/31/1987CA1219981A1 Telephone systems
03/31/1987CA1219980A1 Backup device for a subscriber terminal in a digital concentrator
03/31/1987CA1219939A1 Exchange system
03/25/1987EP0215437A2 Supervisory system in communication system
03/25/1987EP0215309A2 Message taking an retrieval system
03/25/1987EP0215167A1 Instant speaker algorithm for digital conference bridge
03/25/1987EP0105916B1 Method and apparatus for identifying faulty communications circuits
03/24/1987US4653090 Terminal for use with a communication system
03/24/1987US4653089 Personal telephone adapter
03/24/1987US4653085 Telephone switching system adjunct call processing arrangement
03/24/1987US4653084 Remote actuated switch
03/24/1987US4653045 Interactive facility control arrangement
03/24/1987US4653043 Pre-cutover verification of switching system subscriber lines served via digital carrier facilities
03/24/1987US4652701 Ringing application circuit
03/24/1987US4652700 Electronic audio communications system with versatile user accessibility
03/24/1987CA1219663A1 Data call transfer
03/19/1987DE3532644A1 Method for fault analysis of microprocessor-controlled communications systems, in particular centrally controlled telephone switching systems
03/19/1987DE3531867A1 Method and circuit arrangement for changing name key contents in a centrally controlled communications PBX system
03/18/1987EP0214499A2 Controlling multi-port hunt groups in a distributed control switching system
03/18/1987EP0214398A1 Method for supervising and controlling the traffic in digital transmission networks
03/18/1987EP0214347A1 Interactive educational system with voice reaction and access using tone-generating telephone
03/17/1987US4651343 Piezoelectric apparatus for positioning optical fibers
03/17/1987US4651134 Switched capacitor coupled line receiver circuit
03/17/1987US4650932 Key telephone system
03/17/1987US4650929 Communication system for videoconferencing
03/12/1987WO1987001547A1 Subscriber line card arrangement
03/12/1987DE3531872A1 Method and circuit arrangement for automatic dialling of destination subscriber telephone number parts in a centrally controlled communications PBX system
03/12/1987DE3531170A1 Circuit for connecting two primary or secondary connection lines and the telephone sets assigned to them
03/12/1987DE3531168A1 Method for picking up calls arriving on separate lines
03/12/1987DE3531147A1 Test device for a telephone switching system
03/11/1987EP0213408A1 Circuit arrangement for telecommunication exchanges, in particular for telephone exchanges equipped with control processors and traffic-measuring devices
03/11/1987EP0213382A1 Circuit arrangement for telecommunication exchanges, particularly for telephone exchanges equipped with control processors and traffic-measuring devices
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