H04M 3 - Automatic or semi-automatic exchanges

Patents for H04M 3 - Automatic or semi-automatic exchanges (99,881)
09/1986
09/02/1986	US4609789 Verification via cable analyzer
09/02/1986	CA1210880A1 Signal detection circuit
09/02/1986	CA1210879A1 Telecommunications system
09/02/1986	CA1210878A1 System for producing encoded and decoded voice, internal audio tones, and data communication within a time division multiplex network
09/02/1986	CA1210840A1 Digital switching network for telecommunications exchange
09/02/1986	CA1210839A1 Centralized supervisory system
08/1986
08/28/1986	WO1986005054A1 Arrangement for accessing and testing telecommunication circuits
08/27/1986	EP0192107A2 Call-handling or information position for a telephone exchange, especially a multiple operator's position exchange
08/26/1986	US4608693 Signal processing system
08/26/1986	US4608461 Subscriber circuit for a telephone network
08/26/1986	US4608460 Comprehensive automatic directory assistance apparatus and method thereof
08/26/1986	CA1210541A1 Conferencing system adaptive signal conditioner
08/26/1986	CA1210455A1 Multi-channel multi-cell optoelectronic switching networks for multi-service telecommunications systems
08/26/1986	CA1210452A1 Biased reactor maintenance termination unit
08/20/1986	EP0191077A1 Method and apparatus for testing communication systems
08/20/1986	CN85109433A Data subsystem traffic control apparatus and method
08/19/1986	US4607364 Multimode data communication system
08/19/1986	US4607363 Buffer device for a voice transmission network
08/19/1986	US4607362 Method of and circuit arrangement for establishing conference connections in a switching system
08/19/1986	CA1210172A1 Telephone answering system
08/19/1986	CA1210171A1 Method and apparatus for signaling an existing telephone communication between picture telephone apparatuses
08/14/1986	WO1986004763A2 Controlling multi-port hunt groups in a distributed control switching system
08/14/1986	WO1986004740A2 Processing sequence calls in a distributed control switching system
08/12/1986	US4606021 Digital conference circuit
08/12/1986	US4605827 Line fault discriminator
08/12/1986	US4605823 Phone conference system
08/12/1986	CA1209732A1 Active impedance line feed circuit with improved ground fault protection
07/1986
07/31/1986	WO1986004474A1 Integrated message service system
07/31/1986	WO1986004473A1 Integrated message service system
07/30/1986	EP0188676A2 Method for the multiple use of direct call keys at terminals, especially at operation positions in telephone exchanges, especially multiple operator's position exchanges
07/30/1986	CN85100298A Telephone switching system of packet distribution type
07/29/1986	US4603417 PCM coder and decoder
07/29/1986	US4603415 System for linking channel group in digital communication network
07/29/1986	US4603236 Secretarial answering system with distributed processing
07/29/1986	US4603233 Connection apparatus for the measurement, observation and manipulation of events in a large number of telephone circuits
07/23/1986	EP0187945A2 Method for the transmission of signals between a data exchange and a telephone exchange, especially a private branch exchange
07/22/1986	US4602338 Impedance measurement in 4-wire to 2-wire converters
07/22/1986	US4602129 Electronic audio communications system with versatile message delivery
07/22/1986	US4602128 Automatic redialing arrangement for multi-line telephone station sets
07/16/1986	EP0187696A2 Full duplex conferencing system
07/16/1986	EP0187366A2 Line circuit for driving a ringer and a service indicating lamp in a telephone set
07/16/1986	EP0110933B1 Apparatus for through-connection testing in a digital telecommunication network
07/15/1986	US4601064 Communication system
07/15/1986	US4600816 Attenuator adapted for clip mounting to connecting block terminals
07/15/1986	US4600814 Automated system for establishing telephone voice connections
07/15/1986	US4600812 Communication system having abbreviated dialing access
07/15/1986	US4600811 Subscriber line interface circuit
07/15/1986	US4600810 Telephone line tester
07/15/1986	US4600809 Telephone systems
07/15/1986	CA1207904A1 Automatic audience survey system
07/15/1986	CA1207877A1 Self-routing steering network
07/15/1986	CA1207874A1 Call interceptor
07/09/1986	EP0186873A2 Protector circuit
07/09/1986	CN85106665A New line circuit direct dialing technique for dial telephone pbx
07/08/1986	US4599493 Multi-line telephone control system
07/08/1986	CA1207477A1 Electronic communication message system
07/08/1986	CA1207414A1 Acd management information system
07/08/1986	CA1207385A1 Circuit for selectively exciting one of a pair of light emitting diodes
07/02/1986	EP0186605A2 Traffic simulation circuit for the supervision of analogous or digital telephone exchanges
07/02/1986	EP0185777A1 Safety circuit system for overvoltage protection of multi-wire lines
07/02/1986	CN85108230A Ringing signal sending circuit
07/01/1986	US4598363 Adaptive delayed polling of sensors
07/01/1986	US4598173 Interface circuit for a subscriber line circuit
06/1986
06/25/1986	EP0185445A2 Method and apparatus for controlling digital voice recording and playback over telephone lines and adapted for use with any host computer
06/25/1986	EP0185295A2 A call progress monitor for a computer telephone interface
06/25/1986	EP0185213A2 Circuit arrangement for overcharge protection of a subscriber current supply circuit, especially in a digital telephone exchange
06/25/1986	EP0185032A1 Message waiting alerting method
06/24/1986	US4596904 Test apparatus for telephone lines
06/24/1986	CA1206653A1 Phone conference system
06/24/1986	CA1206651A1 Telephone substation transmitter muting circuit
06/24/1986	CA1206649A1 Subscriber line interface circuit
06/24/1986	CA1206648A1 Subscriber circuit for a telephone network
06/24/1986	CA1206644A1 Apparatus for isolating the voice frequency path from the floating battery feed during signalling
06/24/1986	CA1206643A1 Supervision and dial pulse detection circuit for a telephone subscriber line
06/24/1986	CA1206640A1 Ringing signal generator
06/19/1986	WO1986003645A1 Watch pager system and communication protocol
06/19/1986	WO1986003644A1 An arrangement in a telephone exchange
06/18/1986	EP0184883A2 Traffic simulation device for testing switching exchanges, taking into account the subscriber system interaction
06/18/1986	EP0184606A2 Pager watch system utilizing time slot communication
06/18/1986	EP0066597B1 Telephone exchange
06/17/1986	US4596041 Participant-identification recording and playback system
06/17/1986	US4596015 Failure detection apparatus for use with digital pads
06/17/1986	US4595796 Method of and a circuit arrangement for determining current criteria in the lines of a telephone system
06/17/1986	CA1206237A1 Method of and circuit arrangement for setting up a conference call
06/10/1986	US4594704 Spare subscriber terminal device in a digital concentrator
06/10/1986	US4594480 Apparatus for automatically checking the correspondence between the numerical codes of telephone subscribers and the different transmission and distribution identification codes of the telephone pair assigned to each subscriber
06/10/1986	US4594476 Broadcast interactive telephone system
06/10/1986	CA1205933A1 Interface circuit for remote control of a pabx
06/05/1986	WO1986003359A1 Automatic redialing arrangement for multi-line telephone station sets
06/05/1986	WO1986003358A1 Loop around data channel unit
06/05/1986	WO1986003357A1 Method and apparatus for looping around a digital transmission line at a channel unit
06/03/1986	US4593157 Directory interface and dialer
06/03/1986	US4593156 For a subscriber line interface circuit having a tip lead
05/1986
05/28/1986	EP0182475A1 Signal amplifier and telephone line feed circuit
05/27/1986	US4592044 Apparatus and method for checking time slot integrity of a switching system
05/27/1986	US4591827 PCM coder-decoder
05/27/1986	US4591665 Method and apparatus for providing call tracing service
05/27/1986	US4591664 Multichannel interactive telephone answering apparatus
05/27/1986	CA1205230A1 Electronic hold circuit
05/27/1986	CA1205229A1 Electronic hold release circuit

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