Patents
Sitemap › H04 - Electric communication technique › H04M - Telephonic communication › H04M 9 - Arrangements for interconnection not involving centralised switching
Patents for H04M 9 - Arrangements for interconnection not involving centralised switching (8,105)
11/1984
11/27/1984US4485272 Acoustic feedback cancelling electro-acoustic transducer network
11/20/1984US4484034 Anti-larsen-effect arrangement in a telephone station equipped with a loudspeaker
11/20/1984CA1178385A1 Adaptive echo cancelling circuit for use in a long- distance telephone network
11/08/1984WO1984004436A1 Integrated voice/data/control switching system
11/08/1984WO1984004435A1 Variable bandwidth switching system
10/1984
10/23/1984US4479085 Power source circuit
10/09/1984CA1175964A1 Two wire voice and data subscriber loop
10/03/1984EP0120325A1 Circuit arrangement for a hands free telephone
10/03/1984EP0120324A2 Circuit arrangement for an automatic telephone exchange with "hands free" phones facility
09/1984
09/19/1984EP0118920A2 Automatic telephone exchange with hands free operation
09/18/1984CA1174773A1 Electronic key telephone system
09/05/1984EP0117362A2 Broad band network system
09/04/1984US4470140 Distributed switching network
09/04/1984CA1173910A1 Radiotelephone with hands-free operation
08/1984
08/30/1984WO1984003407A1 Speakerphone control circuit
08/28/1984CA1173576A1 Key telephone line circuit
08/21/1984CA1173183A1 Interface circuit with flux cancelling transformer circuit
08/15/1984EP0115894A1 TDM loop telecommunication system comprising a first and a second transmission line
08/14/1984US4465902 Digital space phone system
07/1984
07/25/1984EP0114008A2 Telephone set with receiving amplifier provided with an anti-Larsen arrangement
07/10/1984US4459434 Home telephone exchange
07/04/1984EP0112728A1 Subscriber telephone system
07/04/1984EP0112678A1 A telecommunications system
06/1984
06/26/1984US4456792 Voice switching arrangement for telephone conferencing
06/26/1984US4456789 Audio teleconferencing
06/19/1984CA1169597A1 Home communications and control system
06/13/1984EP0110464A1 Private branch exchange
06/13/1984EP0109964A1 Synchronization in a communication network of interconnected rings
06/12/1984US4454384 Hands free telephone with switchable gain in the two speech signal paths
06/07/1984WO1984002207A1 A memory cartridge for connection to a telephone switching arrangement
06/07/1984WO1984002206A1 A telephone switching arrangement
06/05/1984US4453039 Arrangement for avoiding annoying sustained oscillations in a closed-loop system and loud-speaking telephone set employing this arrangement
06/05/1984CA1168770A1 Idle time slot seizure and transmission facilities for loop communication system
05/1984
05/23/1984EP0109260A2 Telephone conference system
05/22/1984CA1167988A1 Line powered transformerless loudspeaking telephone
05/15/1984US4449238 Voice-actuated switching system
05/02/1984EP0106883A1 Intercommunication system
05/01/1984US4446338 Telephone lines status sensor
05/01/1984CA1166777A1 Home telephone exchange
04/1984
04/24/1984US4445004 A diamine crosslinked by an epichlorohydrin-modified polyamide
04/03/1984US4440989 Key telephone area voice paging circuit and method
02/1984
02/21/1984US4433435 Arrangement for reducing the noise in a speech signal mixed with noise
02/14/1984US4432089 Digital loop transceiver for interfacing a digital PABX to a digital subscriber set via a subscriber line
02/08/1984EP0100080A2 Voice detection filter
02/01/1984EP0099761A2 Junction circuit for coupling an additional line to an intercommunication set
01/1984
01/24/1984CA1161177A1 Multiple line telephone instrument
01/17/1984US4426697 Bus system with address and status conductors
11/1983
11/10/1983WO1983003939A1 Intercommunication system
11/08/1983US4414432 Pseudo-full duplex television/telephone loudspeaker system
10/1983
10/25/1983US4412353 Mixing circuit
10/25/1983US4412102 Key telephone system
10/18/1983US4410767 Key telephone system
10/13/1983WO1983003512A1 A voice-actuated switching system
10/04/1983US4408102 Two-wire exchange telephone system
09/1983
09/20/1983CA1154184A1 Circuits and methods for initializing the loop current of a telephone set
09/20/1983CA1154182A1 Telephone systems
08/1983
08/30/1983US4401847 Telephone communication system
08/30/1983CA1153137A1 Parallel operation of telephone equipment on a digital loop
08/23/1983US4400584 Speakerphone for radio and, landline telephones
08/23/1983US4400581 Incoming audio detection circuit for a speaker telephone
08/23/1983CA1152593A1 Digital loop conferencing signal correction arrangement
08/02/1983US4396802 Aswixs remote speaker and handset set
08/02/1983US4396799 Combination of a loudspeaking telephone set and a hand set for soft speaking
07/1983
07/26/1983US4395596 Multi-line controller
07/19/1983US4394544 Line circuit for multiple line telephone
07/19/1983CA1150433A1 Loudspeaker telephone apparatus
07/07/1983WO1983002379A1 Digital loop transceiver for interfacing a digital pabx to a digital subscriber set via a subscriber line
07/05/1983US4392243 Transceiver having interphone system
07/05/1983US4392024 Electronic key telephone set circuit for permitting dialing during failure of commercial power supplied to the set
07/05/1983CA1149530A1 Key telephone line shunt detector circuit
06/1983
06/29/1983EP0082755A1 Telephone set with speech amplifiers
06/28/1983CA1149091A1 Loudspeaking substation circuit
06/14/1983CA1148240A1 Telephone exchange systems utilizing telephone sets
06/08/1983EP0080537A1 Improvements in and relating to speech direction detection circuits for telephone communication devices
05/1983
05/25/1983EP0079426A1 Data communication system
05/24/1983US4385207 Line powered transformerless loudspeaking telephone
05/11/1983EP0078714A1 Communication set and method
05/10/1983US4383315 Idle time slot seizure and transmission facilities for loop communication system
05/10/1983US4383137 Key telephone system with multiple processor control
05/10/1983CA1146245A1 Keyless and indicatorless local telephone switching system
05/03/1983US4382163 Microcomputer controlled key telephone line circuit
04/1983
04/26/1983CA1145496A1 Microcomputer controlled key telephone line circuit
04/26/1983CA1145444A1 Data handling circuits
03/1983
03/29/1983US4378603 Radiotelephone with hands-free operation
03/22/1983US4377726 Selective paging and intercommunication system
03/15/1983US4376875 Keyless and indicatorless local telephone switching system
03/15/1983CA1143071A1 Computer input/output arrangement
03/08/1983CA1142663A1 Key telephone exclusion circuit
02/1983
02/15/1983US4374308 I-Use indication in a telephone keyset
02/08/1983USRE31144 Multi-station telephone switching system
02/03/1983WO1983000412A1 Idle time slot seizure and transmission facilities for loop communication system
01/1983
01/11/1983US4368358 Loop sharing in digital systems
01/11/1983CA1139469A1 Key system protective apparatus
12/1982
12/15/1982EP0066668A1 Method of operating a telephone system
12/14/1982US4363936 Telephone network including common equipment with message information and control information circuits for connecting to stations having multifunction telephones
11/1982
11/30/1982CA1136785A1 Hands free answer intercom
11/30/1982CA1136784A1 Office line connection circuit during service interruptions in key telephone apparatus
11/24/1982EP0065335A1 Device for avoiding sustained disturbing oscillations in a closed-loop system and loud-speaking telephone apparatus utilising this device
11/16/1982US4359606 Voice switching control system
11/09/1982CA1135432A1 Telephone signaling circuit
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