Patents
Sitemap › H04 - Electric communication technique › H04M - Telephonic communication › H04M 19 - Current supply arrangements for telephone systems
Patents for H04M 19 - Current supply arrangements for telephone systems (7,475)
07/1999
07/20/1999US5926533 Computer-based method and apparatus for controlling, monitoring, recording and reporting telephone access
07/15/1999DE19800724A1 Arrangement for indicating an operating failure in an electrical communications device, esp. an emergency and/or information device
07/14/1999EP0928447A2 Method and arrangement for controlling functions in a programme-controlled circuit in the event of operating voltage failure
07/14/1999CN1222795A Wire connected digital information transmission device
07/13/1999US5924046 Portable radio telephone with sound off-hook production
07/13/1999US5924044 Modular communication device and method of providing communications therewith
07/08/1999WO1999034591A1 Method for connecting a remotely powered peripheral unit
07/08/1999WO1999034581A1 Telecommunications terminal card
07/08/1999WO1999034541A1 Method and apparatus for maintaining availability of lifeline telephony service on a hybrid fiber-coax network
07/07/1999CN1222261A Circuitry for voltage pole reversal
07/06/1999US5920592 Data transmitter-receiver
07/06/1999CA2164247C Ring discriminator
07/06/1999CA2157497C Power supply controller for an optical fibre telecommunications system
07/01/1999WO1999033254A1 System and method for allowing distinctive alerting
07/01/1999DE19758273A1 Emergency power supply system for ISDN terminal device not having back-up power supplies
06/1999
06/29/1999US5918189 Exchangeable hardware module for radiotelephone
06/24/1999WO1999031909A1 System, method, and apparatus for delayed call answering
06/23/1999EP0924955A2 Arrangement for wireline digital message transmission
06/23/1999CN1220798A Telecommunication circuit and telecommunication device
06/23/1999CN1220565A Portable communication terminal
06/23/1999CN1220540A Ringing current transducer
06/22/1999CA2256804A1 Portable radio information terminal, message-notification method, recording medium and microcomputer
06/16/1999CN1219816A Slow-start and over-current protection circuit for ringing current generator
06/16/1999CN1219815A Secondary power tube driving circuit for medium and large power ringing current converter
06/15/1999US5912963 Method and apparatus for providing an alternate telecommunications network
06/15/1999US5912958 On-hold device
06/15/1999US5912957 Technique for reconnecting office line to key telephone system after power failure
06/15/1999US5912513 Telecommunication device
06/12/1999CA2251663A1 Arrangement for line-conducted digital telecommunication
06/10/1999WO1999029098A2 Subscriber line interface circuit
06/10/1999DE19855918A1 Voltage equalization device for DC supply system
06/09/1999EP0920769A2 Arrangement in which a useful signal is transmitted between at least two device units
06/03/1999WO1999027704A2 Subscriber line interface circuit
06/03/1999WO1999027703A2 Subscriber line interface circuit
06/02/1999EP0920225A1 Portable cellular phone
06/02/1999CN1218360A Portable cellular phone
06/02/1999CN1218347A Communication support system in which ringing sound control processing is performed in response to call from telephone network
05/1999
05/26/1999EP0918429A2 Ringing sound control processing system in response to a telephone call
05/26/1999EP0917795A1 Programmable cellular telephone with scheduled function activation and deactivation
05/26/1999EP0749654B1 Compact telephone set
05/26/1999EP0587575B1 Telephone line interface circuit with voltage switching
05/25/1999US5907606 Telephone-line powered coin telephone chassis
05/20/1999WO1999011096A3 Modular digital telephone system and method including a universal telephony shelf
05/19/1999EP0917339A2 Method and apparatus for reducing power dissipation in dc termination circuit
05/19/1999EP0917338A1 Dual-limit current-limiting battery-feed circuit for a digital line
05/19/1999EP0917296A1 Battery casing for mobile telephone
05/19/1999EP0916191A2 A wire bound telecommunications device and a power supply circuit
05/18/1999US5905786 Console and extension telephone system
05/12/1999EP0915611A1 Transformerless digital-line battery feed circuit
05/12/1999DE19750863A1 Method of supplying current to bus-supplied ISDN terminals
05/12/1999DE19749730A1 Calling signal unit for portable telephone
05/11/1999US5903448 Four quadrant flyback converter, method of operation thereof and power plant employing the same
05/11/1999US5903076 Vibration actuator for pager
05/04/1999US5901221 Driving stage for driving differential amplifiers of a subscriber line interface circuit
05/04/1999US5901219 In a telephone signal
05/04/1999US5900680 Circuit arrangement for supplying an operating voltage from an operating voltage source to a plurality of connectable and detachable circuit units
04/1999
04/29/1999WO1999021101A1 Apparatus and method for configuring settings of a portable intelligent communications device during a meeting
04/29/1999CA2308165A1 Apparatus and method for configuring settings of a portable intelligent communications device during a meeting
04/28/1999EP0912030A2 Portable communication terminal
04/28/1999CN1215535A Remote test of wireless subscriber connection
04/28/1999CN1215525A Method and arrangement for increasing onhook voltage
04/27/1999US5898364 Electronic equipment having vibration motor
04/27/1999US5898296 Isolation regulator
04/21/1999EP0909501A1 An arrangement for controlling subscriber interface circuits
04/21/1999EP0909499A1 Telephone identification calling apparatus and procedures
04/21/1999CN1214836A Telecommunication device and a method for providing ringing information
04/15/1999WO1999018705A1 Visual alarm for a communication module
04/13/1999CA2167996C Switchmode power converter for telephone subscriber line interface circuits
04/06/1999US5892817 Wireless system for alerting individual to incoming telephone call
04/06/1999CA2104001C Radio with silent and audible alerts
04/01/1999WO1999003259A3 Method and apparatus for controlling a telephone ring signal
04/01/1999DE19743138A1 Emergency current supply for car emergency and/or accident call system
03/1999
03/31/1999EP0905962A1 Automatic service station for cellular telephones
03/31/1999EP0904619A1 Circuitry for voltage pole reversal
03/31/1999CN1212551A Power supply adapter circuit
03/30/1999US5889858 Standby high voltage analog line feed
03/30/1999US5889509 Communications terminal apparatus and display method thereof
03/25/1999WO1999014838A1 Method and system for distribution of stand-by electric power
03/25/1999WO1999000970A3 Circuit for transmitting messages
03/25/1999DE19740334A1 Power supply circuit for telecommunications terminal
03/24/1999EP0903927A1 MOS transistors circuit having a transformer/data interface function
03/24/1999EP0903030A1 Device at telecommunication system
03/24/1999CN1212109A Communication network terminal supporting plurality of applications
03/23/1999US5887248 Audible tone signal service apparatus and method of a digital mobile services switching center
03/18/1999WO1999013628A1 Telephone apparatus
03/18/1999WO1998048541A3 Direct digital access arrangement circuitry and method for connecting to phone lines
03/17/1999CN1211369A Incoming call alerting method for a radio communication apparatus connected to an external apparatus
03/17/1999CN1211155A Electro-mechanical-acoustic transducing device
03/16/1999US5884156 Portable communication device
03/16/1999US5883892 Storage type data communication terminal
03/11/1999WO1998058301A3 A circuit for controlling an ac/dc buzzer load
03/11/1999DE19740742A1 Radio-controlled telephone accessory ringer
03/10/1999EP0901263A2 Method for handling phone numbers in mobile station and mobile station
03/10/1999EP0901196A2 Connector mating detection device for fail-safe high power operation system
03/10/1999CN1210431A Communication device to inform user of call differently according to caller
03/09/1999US5881148 T1 channel bank control process and apparatus
03/09/1999US5881147 Ring varying technique for a telephone
03/09/1999US5881129 Self-monitoring line interface circuit
03/04/1999WO1999011096A2 Modular digital telephone system and method including a universal telephony shelf
03/03/1999EP0899934A1 Adapter circuit of the supply voltage
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