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)
10/1989
10/31/1989US4878239 Anonymous interactive telephone system with expanded outward calling features
10/31/1989US4878217 Data outputting device
10/31/1989US4878048 Channel redundancy in a digital loop carrier system
10/31/1989CA1262581A1 Voice and data transmission system
10/25/1989EP0338699A2 Transient protection circuit
10/25/1989EP0338640A2 Meshed telecommunication network
10/25/1989EP0338126A2 Method and apparatus for testing twisted-pair interconnections of a local area network
10/25/1989EP0338107A1 Overvoltage protection circuit used with a pair of telephone lines or similar data communication channels
10/25/1989EP0254743A4 Pay-per-view catv system.
10/25/1989CN1036674A Data path checking system
10/24/1989US4876711 Series connected telephone service system
10/24/1989US4876708 Cordless telephone system
10/24/1989US4876707 Two-directional call forwarding device
10/24/1989US4876620 Protection devices and arrangements for telephone lines
10/24/1989CA1262484A1 Telephone system adapted to telemarketing
10/18/1989EP0337539A2 Telematic system of information and advertising messages for locations with a large attendance of people
10/18/1989EP0337524A1 Device for testing the conference establishing units in a digital exchange
10/18/1989EP0337163A2 Circuit arrangement for switching-over from normal operation to emergency operation and reversely in a telephone switching device
10/18/1989CN2046299U Program control circuit concentrator
10/17/1989US4875232 Telephone power distribution and isolation system
10/17/1989CA1262385A1 Pager watch system utilizing time slot communication
10/11/1989EP0336770A2 Method and apparatus for predictive dialing
10/11/1989EP0336524A2 Electronic audio communication system with user controlled message address
10/11/1989EP0335956A1 Direct access test unit for central office
10/10/1989US4873719 Enhanced calling number delivery service system
10/10/1989US4873718 Feature telephone integration device
10/10/1989US4873716 Path allocation arrangement for multi-terminal groups
10/10/1989US4873687 Failing resource manager in a multiplex communication system
10/10/1989CA1262274A1 Isdn d channel handler
10/10/1989CA1262273A1 Method of and an arrangement for forwarding a customer order
10/10/1989CA1262272A1 Automated message chronicling system
10/05/1989WO1989009530A1 Automated interactive mass communications system
10/05/1989WO1989009525A1 Call traffic control
10/05/1989WO1989009414A1 Apparatus and method for mapping the connectivity of communications systems with multiple communications paths
10/05/1989DE3808414A1 Telephone handset with visual display device
10/04/1989EP0335813A2 Redundant message processing and storage
10/04/1989EP0335710A2 Translation communication system
10/04/1989EP0335510A2 A data path checking system
09/1989
09/27/1989EP0334612A1 Call traffic control
09/27/1989EP0334549A2 Method and apparatus for wideband transmission of digital signals between a telephone central office and customer premises
09/26/1989US4870680 Communication apparatus having a communication hold function
09/26/1989US4870675 Remote testing of metallic loops with a trans hybrid signal
09/26/1989US4870638 Remote maintenance system for a digital communication network
09/26/1989CA1261922A1 Circuit for detecting current variations
09/26/1989CA1261495A1 Line terminating apparatus
09/26/1989CA1261493A1 Communication system having unified messaging
09/26/1989CA1261441A1 Programmable subscriber set
09/26/1989CA1260636A1 Watch pager system and communication protocol
09/26/1989CA1260589A1 Communication system having automatic circuit board initialization capability
09/26/1989CA1260583A1 Call distribution arrangement
09/26/1989CA1260582A1 Terminal based adjunct call manager for a communication system
09/26/1989CA1260535A1 Voltage surge arrester circuits
09/26/1989CA1260171A1 Protection arrangement for a telephone subscriber line interface circuit
09/26/1989CA1260124A1 Subscriber's line switching control system
09/26/1989CA1260123A1 High speed packet switching arrangement
09/20/1989EP0332977A2 Method of establishing data transfer connexions in a telecommunication exchange
09/19/1989US4868703 Solid state switching device
09/14/1989DE3807007A1 Method for directly setting up telecommunications connections, in particular telephone connections, on workstations or answering stations of multi-user dealing room systems
09/14/1989DE3807006A1 Method for identifying the call type of external lines connected to multi-user dealing room systems
09/13/1989EP0332197A2 A ring transmission system
09/12/1989US4866768 Station line interface circuit for a telecommunication network
09/12/1989US4866758 Phone management server for use with a personal computer LAN
09/12/1989US4866756 Interactive computerized communications systems with voice input and output
09/12/1989US4866753 Telephone installation having a radio link
09/12/1989US4866587 Electronic ringing signal generator
09/07/1989DE3805976A1 Method and arrangement for storing telecommunications messages
09/07/1989DE3805975A1 Method and arrangement for storing telecommunications messages
09/06/1989EP0330961A1 Telephone line interface circuit
09/05/1989US4864623 Method of recognizing a control command in a system, and interactive system for carrying out the method
09/05/1989US4864600 Telephone call processing system
09/05/1989US4864597 Cable pair tester
08/1989
08/30/1989EP0330441A2 Interface to and operation of a voice messaging system
08/30/1989CN2043808U Collector of common line telephone
08/29/1989US4862498 Method and apparatus for automatically selecting system commands for display
08/29/1989US4862496 Routing of network traffic
08/29/1989US4862491 Remote disconnection and short-circuiting apparatus and method
08/29/1989US4862452 Digital signal processing system
08/29/1989US4862314 System for providing power to a central office protector module with alarm indicator and including remote alarm indication
08/29/1989US4862309 Protection circuit for battery feed circuit
08/29/1989CA1258930A1 Active impedance line feed circuit
08/23/1989CN1035030A Bus-type master-slave mutual-call inter-com
08/22/1989US4860344 Circuit arrangement for telecommunications switching systems, particularly telephone switching systems, etc.
08/22/1989US4860339 Programmable telephone/dictation terminal and method of operating same
08/22/1989US4860332 Apparatus for the automatic in-circuit testing of subscriber line interface circuits and method therefor
08/22/1989US4860281 Individual subchannel loopback in the PCM interfaces of a digital telephone exchange with control of the outbound path
08/22/1989US4860230 Signal recognition system
08/22/1989CA1258713A1 Process for modifying operation of application program
08/16/1989EP0327872A1 Process for the testing and fault analysis of electric circuit modules
08/16/1989CN1034837A Method of asynchronous duplex data communication between two stations relating to specific services to be performed through a common communication channel and a station for implementing the method
08/15/1989US4858224 Diagnostic method of equipment and system using the same
08/15/1989US4858223 Security arrangement for a telecommunications exchange system
08/15/1989US4858120 System for regulating arrivals of customers to servers
08/15/1989CA1258548A1 System and method for defining and providing telephone network services
08/10/1989WO1989007377A1 Communications network state and topology monitor
08/09/1989EP0327471A1 Device for processing telephonic signals comprising digital signal processing devices common to a plurality of subscribers lines
08/09/1989EP0327359A1 Protector device
08/09/1989CN2042646U Direct dial repeater for automatic telephone exchanger
08/08/1989US4856066 Speech communication system and method
08/08/1989US4856060 Solid state telephone protector module
08/08/1989US4856059 Semiconductor subscriber line interface circuit with enhanced survivability
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