Patents
Patents for H04M 19 - Current supply arrangements for telephone systems (7,475)
08/1997
08/05/1997US5654592 Power supply controller
07/1997
07/31/1997WO1997022887A3 Method for displaying a 'low battery' state in electrical equipment with electrical energy stores and electrical equipment with electrical energy stores with means for displaying a 'low battery' state
07/31/1997DE19653588A1 Cordless telephone call detection circuit
07/30/1997EP0786093A1 Method for detecting a signal
07/24/1997WO1997026633A1 Mobile telephone warning device
07/23/1997CN1155204A Subscriber's line interface circuit capable of realizing by CMOS circuit
07/22/1997US5651052 Apparatus and method for incoming call detection and alarm circuitry for cellular telephones
07/17/1997DE19600935A1 Mains-independent radio receiver with continuous standby capability
07/15/1997US5649020 Tactile alerting system
07/15/1997US5649009 Differential longitudinal amplifier for a subscriber line interface circuit
07/15/1997US5649007 Telephone set of distinctive ringing type capable of generating different calling sounds after the telephone set is connected to remote calling party
07/15/1997US5649006 Communication apparatus having function of generating calling signal
07/15/1997US5649002 Method and apparatus for detecting a telephone CPE alerting signal
07/10/1997DE4227601C1 Call tone control for telephone handset
07/03/1997DE19654576A1 Tragbares schnurloses Endgerät mit getrennter Schwingungserzeugungsschaltung A portable wireless terminal with separate wave generating circuit
07/02/1997EP0782257A1 Impedance matching device for supply line
06/1997
06/26/1997WO1997022887A2 Method for displaying a 'low battery' state in electrical equipment with electrical energy stores and electrical equipment with electrical energy stores with means for displaying a 'low battery' state
06/25/1997EP0780991A2 Adaptor cable for a mobile radio
06/24/1997US5642413 Telephone call alert device with selectable alert modes
06/24/1997US5642412 Isolated high impedance, DC current sources for telecommunications applications
06/19/1997DE19620834C1 Cordless telephone combined base station and charging station
06/19/1997DE19547019A1 Verfahren zum Anzeigen des Zustands "Energiespeicher erschöpft" in Elektro-Geräten mit Elektro-Energiespeichern und Elektro-Geräten mit Elektro-Energiespeichern zum Anzeigen des Zustands "Energiespeicher erschöpft" A method for displaying the state "low energy store" in electrical appliances with electric-energy storage and electric appliances with electric energy storage devices for indicating the state "low energy store"
06/17/1997US5640441 Apparatus and method for incoming call detection and alarm circuitry for cellular telephones
06/12/1997WO1997021300A1 Method and apparatus for generating a ringing signal
06/12/1997WO1997021298A2 Method of detecting operating states of an electrical apparatus and electrical apparatus for detecting apparatus-specific operating states
06/12/1997CA2239051A1 Method and apparatus for generating a ringing signal
06/11/1997CN1151648A Circuit for controlling on-hook voltage by use of balanced amplifier without supplying constant current to balanced amplifier
06/11/1997CN1151644A Ring trip circuit having simple trip detecting circuit of high response speed
06/10/1997US5638421 Apparatus and method for incoming call detection and alarm circuitry for cellular telephones
06/05/1997WO1997020426A1 Terminal for wirebound telecommunication
06/04/1997EP0776565A1 Improved communications marketing system
06/04/1997EP0668001B1 Process for programming a base station using a mobile unit
06/03/1997US5636274 Switch controller and method
06/03/1997US5636273 Integrated ring detection circuit and power cross detection circuit with persistence timers
06/03/1997US5635897 Mobile phone alarm
05/1997
05/29/1997WO1997019457A1 Switch with inductor function
05/29/1997WO1997019429A1 Displaying graphic messages in a radio receiver
05/28/1997EP0776115A2 Double-acting mobile communication apparatus for facilitating its hands-free use
05/28/1997EP0775388A1 Power consumption control method and apparatus for a communication system subscriber unit
05/27/1997US5633925 Low loss telephone circuit
05/22/1997DE19543365A1 Ringing circuit with automatic volume control for radiotelephone, door bell or alarm
05/22/1997DE19542730A1 Programmable call signal accessory for telephone handset
05/21/1997EP0632937B1 DC/AC Power supply
05/15/1997DE19543040A1 Incoming telephone call signalling device for ISDN system
05/14/1997EP0773519A2 Vending machine for charging a secondary battery of a mobile phone
05/13/1997US5629931 Information transmission system
05/09/1997WO1997016932A1 Selective notification method for portable electronic devices
05/07/1997EP0772334A2 Radiotelephone
05/07/1997EP0636295B1 Wideband telephone line interface circuit
05/07/1997DE19541018A1 Intercom system with telephone sets for two users
05/06/1997US5627890 Telephone line interface circuit
05/06/1997US5627491 Plural stage circuit with automatic adaptation to first and second voltage ranges of a common voltage source
04/1997
04/30/1997DE19539899A1 Communication apparatus with acoustic calling signal
04/29/1997US5625683 Method of and telephone with call-reminding and auto-dialing
04/24/1997WO1997015135A1 Telephone isolation device
04/24/1997DE19545762C1 Operating condition detection system for cordless mobile telephone
04/24/1997DE19537224A1 Power consumption reduction demand for wireless telephone
04/23/1997CN1148314A sound volume setting device for portable telephone
04/22/1997US5623544 Telephone headset interface circuit
04/22/1997US5623531 Auxiliary power for telephone distribution system
04/22/1997US5623321 Circuit for cutting off power to an active RF component
04/17/1997DE19635288A1 Telephone reception signal, volume changing method
04/16/1997EP0768784A2 Circuit arrangement for displaying information characterising the status of the switching network
04/16/1997CN1147731A Communications terminal apparatus and display method thereof
04/16/1997CN1147730A Radio receiving terminal
04/10/1997DE19635289A1 Current supply control circuit for mobile radio/communications system
04/09/1997CN2251844Y Working stabilizing reliable feeder amplifier
04/08/1997US5619568 Cordless phone with time-out controlled ringer
04/08/1997US5619567 Variable DC feed characteristic in a subscriber line interface circuit
04/08/1997US5619252 Video telephone system and method for transmitting and receiving signals when there is a failure in the system
04/02/1997EP0766448A2 Network powered telecommunication terminal with telephone handset connected to the telecommunication network via a terminal specific-digital signal processing device
04/02/1997EP0766447A2 Data acess arrangement with telephone interface
04/02/1997EP0766436A1 Circuit for a telephone set comprising a light emitting diode power supply
04/02/1997EP0765561A1 Communication device
04/01/1997US5617472 Noise suppression of acoustic signal in telephone set
04/01/1997CA2046248C Power conserving technique for a communications terminal time slot interchanger
03/1997
03/27/1997WO1997011532A1 Incoming calling system
03/26/1997EP0765069A2 Circuit for controlling an on-hook voltage by the use of a balanced amplifier without supplying a constant current to the balanced amplifier
03/26/1997CN1146263A Power management for line powered telecommunication apparatus
03/18/1997US5612998 Integrated interface circuit for driving a subscriber line
03/18/1997CA2062870C Line interface circuit
03/12/1997CN1145001A Circumscribed full-automatic communication connector
03/11/1997US5610978 Ring discriminator
03/06/1997WO1997004574A3 Telephone exchange
03/05/1997EP0760576A1 An Integrated ringer relay circuit and method
03/04/1997US5608795 Telephone line interface circuit
03/04/1997US5608792 Apparatus for drawing and processing electrical power from a communications line
02/1997
02/27/1997DE19630629A1 Faulty operation prevention circuit especially for setting apparatus in cordless telephone
02/25/1997US5606313 Low power addressable data communication device and method
02/20/1997WO1997006630A1 Power supply for telecommunications devices
02/20/1997WO1997006629A1 Remote supply of decentralised (especially narrow-band) devices in wide-band fibre-optic lines and subscriber connection systems having copper remote supply lines
02/19/1997EP0758518A1 Telecommunication system
02/19/1997CN1143292A Ringing current power source of program controlled exchanger
02/18/1997CA2105376C Telephone line interface circuit with voltage switching
02/13/1997DE19529183A1 Fernspeisung von dezentralen (insbesondere Schmalband-) Einrichtungen in optische Breitband-Anschlußleitungen und Kupfer-Fernspeisungsleitungen aufweisenden Teilnehmeranschlußnetzen Remote powering of distributed (in particular narrowband) means having in optical broadband access lines and copper-remote supply lines subscriber access networks
02/12/1997EP0533755B1 Communications-transmission system
02/12/1997CN2247399Y Multi-function domestic robbery-proof alarm device
02/11/1997US5602911 System and method for eliminating bell tap on analog telephones
02/11/1997US5602908 Calling party identifying apparatus and method therefor
02/11/1997US5602900 Radio Telecommunication apparatus
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