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)
10/1983
10/26/1983EP0091999A1 Communications system and central station therefor
10/26/1983EP0091932A1 Telephone switching control arrangement.
10/25/1983US4412282 Microprocessor control circuit
10/13/1983WO1983003512A1 A voice-actuated switching system
10/13/1983WO1983003511A1 Implied principal addressing in a call coverage arrangement
10/13/1983WO1983003510A1 Call coverage arrangement
10/13/1983WO1983003509A1 Call message service
10/12/1983EP0091267A2 Telecommunication system loop-back unit
10/11/1983US4409438 Ringing control circuit in a telephone switching system
10/11/1983CA1155241A1 Diagnostic circuit for pcm connection networks
10/11/1983CA1155224A1 Method of and device for effecting objective quality measures on speech transmission apparatuses
10/11/1983CA1155207A1 Telephone call denial system
10/11/1983CA1155206A1 Testing of subscriber loop pair gain systems
10/05/1983EP0030724B1 Method and device for carrying out objective measurements on digital speech transmission systems
10/04/1983US4408248 Protection circuit
10/04/1983US4408100 Position load distribution and management system for key telephone systems
10/04/1983US4408099 Radio paging system capable of accepting message with access of paging receiver
10/04/1983CA1154889A1 Line hold circuits
10/04/1983CA1154888A1 System for the exchange and distribution of information over a subscribers' telephone network
09/1983
09/28/1983EP0089716A1 Method of and arrangement for establishing a conference connection in a TDM communication system
09/28/1983EP0089687A2 Method of and electronic device for detecting the lifting of the telephone handset in presence of ringing current
09/27/1983US4406925 Message delivery system
09/20/1983US4406004 Ring scheduling apparatus for a digital multiplexed telecommunication system
09/20/1983CA1154182A1 Telephone systems
09/14/1983EP0088289A2 Method for the reception of a dialling prompting signal from the public telephone network by a telecommunication exchange, especially a private telephone exchange
09/13/1983US4404636 Phasor impedance measuring test set
09/13/1983US4404630 Data-extraction circuitry for PCM communication system
09/13/1983CA1153838A1 Telephone circuit for ringing rhythm generation and off hook detection
09/07/1983EP0087849A1 Telephone message communication system
09/07/1983EP0087784A2 Subscriber line circuit comprising low-resistance shuntable feeding resistors and an indication circuit realising different indications
08/1983
08/31/1983EP0086810A1 Wideband switching architecture
08/30/1983US4402074 Switching network test system
08/30/1983US4402008 Wideband switching architecture
08/30/1983US4401861 Semiconductor crosspoint linearizing arrangement
08/30/1983CA1153120A1 Multiprocessor information processing system having fault detection function based on periodic supervision of updated fault supervising codes
08/30/1983CA1153090A1 Connection network control system
08/23/1983US4400587 Overflow and diversion to a foreign switch
08/23/1983CA1152663A1 Apparatus for detecting the closure of a subscriber's line during ringing
08/23/1983CA1152653A1 Multiple-channel voice input/output system
08/23/1983CA1152593A1 Digital loop conferencing signal correction arrangement
08/18/1983WO1983002864A1 A method and apparatus for giving identity to, and selecting one of a plurality of function units
08/18/1983WO1983002863A1 Message delivery system
08/16/1983US4399499 Bi-lateral four quadrant power converter
08/16/1983US4399440 Addressable transducer with a variable frequency oscillation for monitoring a physical quantity
08/16/1983US4399333 Telephone fault detection system
08/16/1983US4399332 Programmable traffic-measuring unit for telecommunication system
08/16/1983US4399330 Communications system, in particular a telephone system, for connecting mobile subscriber terminal devices
08/16/1983CA1152241A1 Telephone loop resistance detector
08/16/1983CA1152206A1 Buffer memory dispersion type video/audio transmission system
08/10/1983EP0085558A2 Supervision of automatic switching systems
08/09/1983US4398066 Automatic power denial circuit for a subscriber line interface circuit
08/03/1983EP0084721A1 Solid state relay
08/02/1983US4396809 Maintenance termination unit
08/02/1983CA1151327A1 Digital conference circuit and method
07/1983
07/26/1983US4395780 Service-integrated communication transmission and exchange system
07/26/1983US4395651 Low energy relay using piezoelectric bender elements
07/26/1983CA1150867A2 Programmable ringing generator
07/20/1983EP0083893A1 System for the transmission of messages to a subscriber's set through a subscriber's line in a telephone installation
07/19/1983US4394543 Telephone line holding circuit
07/19/1983CA1150432A1 Portable telephone line test set
07/19/1983CA1150429A1 Time division digital switching installation for speech and data packet transmission lines
07/12/1983US4393496 Method for feeding call progress tones into conference connections
07/12/1983US4393495 Message translation arrangement for telephony system with romote port groups
07/12/1983US4393491 Automatic self-test system for a digital multiplexed telecommunication system
07/12/1983CA1149917A1 Network connection system
07/12/1983CA1149916A1 Method of providing person locator service
07/05/1983US4392206 Printer
07/05/1983US4392026 Subscriber line testing system
07/05/1983CA1149493A1 Alarm monitoring arrangements for digital telecommunications switching networks
06/1983
06/29/1983EP0082800A1 Terminating circuit for telephone lines
06/28/1983CA1149089A1 Call waiting signal arrangement
06/28/1983CA1149048A1 Call processing monitor system
06/28/1983CA1149047A1 Call processing monitor system
06/23/1983WO1983002205A1 Demultiplexer circuit
06/22/1983EP0081799A1 Method and circuit for establishing a conference connection
06/21/1983US4389720 Distributed digital conferencing system
06/21/1983US4389547 Telephone set
06/21/1983US4389546 Digital announcement system including remote loading and interrogation
06/21/1983CA1148676A1 On-hook/off-hook status check circuit
06/21/1983CA1148637A1 Control system for telephone switching system
06/15/1983EP0081066A1 Electronic text transmitter for the simultaneous or time-shift emission of text-identical or text-different announcements
06/14/1983US4388718 Digital telecommunication system
06/14/1983US4388717 Conference circuit for PCM system
06/14/1983US4388715 Alarm preprocessor logic
06/14/1983US4388501 Audio-visual line test termination device
06/14/1983CA1148286A1 Calling device for subscriber automatic telephone installation with extension stations
06/14/1983CA1148240A1 Telephone exchange systems utilizing telephone sets
06/07/1983US4387457 Digital conference circuit and method
06/07/1983US4387456 Alarm monitoring arrangements for digital telecommunications switching networks
06/07/1983US4387274 Hook flash signal actuated telephone control device
06/07/1983US4387271 Combined telephone and data-transfer system
06/07/1983CA1147875A1 Packet transmission system with voice signal priority
05/1983
05/31/1983US4386424 Broad band telecommunication system
05/31/1983US4386243 Telephone test shoe having resilient latching means
05/25/1983EP0079463A1 Method and circuit for registering the loop current criteria in a telecommunication exchange
05/24/1983US4385359 Multiple-channel voice input/output system
05/24/1983US4385336 Current supplying circuit with shorted-to-ground fault detecting function
05/24/1983US4385230 Digital temperature effect generator
05/18/1983EP0078862A1 Emergency calling device
05/17/1983US4384175 Tone detection method and arrangement for observing and classifying repetitive status signals
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