H04M 9 - Arrangements for interconnection not involving centralised switching

Patents for H04M 9 - Arrangements for interconnection not involving centralised switching (8,105)
12/1988
12/29/1988	DE3720186A1 Method for a computer-controlled switching system, in particular a so-called KEY telephone switching system
12/28/1988	CN88103175A Non-cord telephonic system
12/28/1988	CA1247764A Key telephone system
12/27/1988	US4794641 Data transmission system of key telephone system
12/27/1988	US4794640 Switching control apparatus for intercom-telephone sets
12/21/1988	EP0295470A2 Method for a calculator controlled switching device especially for a so called key telephone exchange with the possibility of call transfer
12/21/1988	EP0295469A1 Method for a calculator controlled switching device, especially for a so-called key telephone switching device
12/13/1988	US4791662 Controlling key-system groups from a distributed control switching system
12/13/1988	US4791629 Communications switching system
12/06/1988	US4790004 Implied principal busy status indicator for covered calls
11/1988
11/30/1988	CN88102826A 音量范围控制电路 Volume range control circuit
11/24/1988	DE3724346A1 Circuit arrangement for dynamic control
11/17/1988	EP0290952A2 Speech control circuitry for a telecommunication terminal
11/15/1988	CA1244978A1 Single line telephone communication system
11/10/1988	DE3714595A1 Communications system (with mixed frequency and IF stage) without its own lines
11/08/1988	CA1244541A1 Communication system having separate unidirectional information signalling
11/01/1988	US4782515 Digitally controlled intercommunications system
11/01/1988	US4782514 Key telephone system
11/01/1988	US4782482 Simultaneous voice and data communications system
11/01/1988	CA1244168A1 Speakerphone for radio and landline telephones
10/1988
10/27/1988	DE3711769A1 Intercom system
10/26/1988	EP0288078A2 Speakerphone using digitally compressed audio to control voice path gain
10/25/1988	CA1243787A1 Variable bandwidth switching system
10/25/1988	CA1243742A1 Communication system administration method and circuitry
10/24/1988	EP0236432A4 Optical fiber bandwidth limiting method.
10/05/1988	CN87214821U Door bell telephone answer back device
10/04/1988	US4776006 Multiplexed data channel controlled telephone system
10/04/1988	CA1242819A1 Integrated voice/data/control switching system
09/1988
09/27/1988	US4774706 Packet handling communications network
09/21/1988	CN88201006U Automatic telephone interconnection arrangement
09/21/1988	CN87204374U Telephone set having automatic on-off electric source for self-selecting users
09/14/1988	EP0282393A1 Device for the realization of the hands free function in a telephone set associated with the functions of gain switching and echo cancelling
09/14/1988	EP0282334A2 Loudspeaking telephone with a frequency shifting circuit
09/07/1988	WO1988006823A1 Internal communication system
09/07/1988	EP0281147A2 Hold detecting and control circuit for a key telephone system
09/06/1988	US4769837 Device for adding intercom functions to a phone system
09/01/1988	DE3705816A1 Selector device for a telephone unit for connecting a plurality of telephone stations to a common telephone line
08/1988
08/31/1988	EP0280381A1 Anti-Larsen effect gain control circuit in a telephone amplifier
08/31/1988	EP0280169A2 System for automatic control of devices, apparata and peripheral units for signal switching and processing
08/31/1988	EP0280105A1 Anti-Larsen device for a telephone set
08/24/1988	EP0137806B1 Speakerphone control circuit
08/18/1988	DE3703447A1 Selective switching mechanism for one for several telephones - has logic circuit responding to engaged-reset state of sets to open-close MOSFET gating circuitry
08/16/1988	US4764954 Automatic gain control in a loudspeaker telephone set
08/16/1988	CA1240743A1 System for selectively coupling a plurality of stations into a single communications path
08/09/1988	US4763354 Key telephone system
08/09/1988	US4763348 Controlled power supply for key telephone system
08/03/1988	EP0276493A2 Method for expanding the connection capacity and line access of call-handling or information positions in telephone exchanges, especially multiple operator's position exchanges
08/02/1988	US4761832 Fiber optic switching network
07/1988
07/28/1988	DE3801055A1 Kommunikationssystem Communication system
07/27/1988	CN88100030A Digitally encoded intercommunication telephone system for neighbourhood telephone service
07/26/1988	CA1239718A1 Key telephone system
07/19/1988	US4759059 Analog telephone circuit for digital telephone system
07/19/1988	US4759055 Key telephone system
07/14/1988	WO1988005240A1 Communications systems
07/12/1988	US4757521 Synchronization method and apparatus for a telephone switching system
07/12/1988	US4757496 Distributed telephone system
07/05/1988	US4756021 Telephone set
07/05/1988	US4755988 Data communications switching device having multiple switches operating at plural selectable data rates
07/05/1988	CA1238966A1 Automatic redialing arrangement for multi-line telephone station sets
06/1988
06/29/1988	EP0272828A2 Communication system dynamic conferencer circuit
06/28/1988	US4754477 Key telephone system
06/28/1988	US4754476 Premises page/intercom system utilizing telephone set component
06/28/1988	US4754452 Optical local area network using a common optical carrier with separate user angle modulation
06/28/1988	US4754419 Adaptive digital filter
06/22/1988	EP0271948A2 Telecommunication circuit
06/22/1988	EP0271946A2 Telecommunication device and circuits used therein
06/16/1988	WO1988004501A1 A stand-alone keyphone system
06/16/1988	EP0142551A4 Variable bandwidth switching system.
06/16/1988	EP0141852A4 Integrated voice/data/control switching system.
06/15/1988	EP0271386A1 Two-directional transmission circuit provided with symmetric means for the automatic variation of the amplification according to the direction of transmission
06/15/1988	EP0271274A2 Implied principal busy status indicator for covered calls
06/08/1988	EP0270189A2 Conference circuit for a digital communication system
06/01/1988	DE3634783C1 Operator's or enquiry station for a telephone switching system, particularly a multiple broker's facility
06/01/1988	DE3634781C1 Circuit arrangement for monitoring connections which are on hold in telephone switching systems constructed as multiple broker's facilities
05/1988
05/31/1988	US4748663 Loudspeaking telephone instrument
05/24/1988	US4747128 Telephone privacy protector
05/19/1988	WO1988003734A1 Telephone conversion device
05/18/1988	EP0267267A1 Hospital signaling and communications system
05/17/1988	US4745592 Coherent photonic telecommunications system
05/11/1988	EP0266870A2 Local area network with a common carrier signal
05/11/1988	EP0266740A2 Telephone conversion device
05/10/1988	US4744103 Computer controlled multi-link communication system
04/1988
04/27/1988	EP0264644A2 Circuit arrangement for simulating the NSI contact by means of the hold circuit in a two-way telephone set
04/26/1988	US4741026 Message signaling arrangement between a switching system and user terminals
04/26/1988	US4741018 Speakerphone using digitally compressed audio to control voice path gain
04/26/1988	US4740967 Dispersed switching telecommunication system
04/26/1988	US4740957 Asynchronous addressable electronic key telephone system
04/26/1988	US4740955 Communications system having voice and digital data capability and employing a plurality of voice and data buses in main service unit and serial packetized transmission to and from telephones
04/21/1988	WO1988002968A1 Telephone system with door intercom station
04/20/1988	EP0264188A1 Improvements in call devices
04/20/1988	EP0263972A2 Electronic hold circuit for a two-way telephone set fed by the subscriber line
04/19/1988	US4739205 Telephone signal multiplexing system
04/19/1988	CA1235541A1 Method and apparatus for operating on companded pcm voice data
04/13/1988	EP0263157A1 Method and device for transferring signals between modules of an electronic unit.
04/05/1988	US4736413 Method for the control of voice channel attenuation
03/1988
03/30/1988	EP0262065A1 Communication device for lobbies of buildings
03/29/1988	US4734932 Telephone local intercom system
03/22/1988	CA1234437A1 Office line interface circuits
03/17/1988	DE3630953A1 Method in a telephone system with two exchange lines and five telephone stations of equal access authorization
03/15/1988	US4731832 Process and apparatus for control of a hands-free telephone set operating in alternation between sending and receiving

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