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)
08/1996
08/28/1996EP0235231B2 Subscriber line card arrangement
08/28/1996CN1130008A Power coupler for coupling power from a transmission line to a node thereon
08/27/1996US5550917 Interface device between a public telephone and an external terminal
08/27/1996US5550894 Device for sequentially altering a communication line for remote diagnostic checks
08/21/1996EP0727900A2 Isolated high impedance, DC current sources for telecommunications applications
08/20/1996US5548592 Home and small business phone system for operation on a single internal twisted pair line and methodology for operating the same
08/14/1996EP0726654A1 Integrable two-way switch for higher voltages
08/13/1996US5546025 Low frequency discrimator using upper and lower thresholds
08/13/1996CA2076323C Call signal generating circuit
08/11/1996CA2169113A1 Integratable reversing switch for elevated voltages
08/08/1996DE19523792C1 Check on remote power supply to terminals of telecommunication system
08/07/1996CN1128474A Portable communication apparatus preventing trouble when battery wears
08/07/1996CN1128468A Telephone apparatus
08/06/1996US5544243 Telephone headset interface circuit
08/06/1996US5544241 Telephone ring detector
08/06/1996US5543669 Remote feed circuit in communication systems
08/01/1996WO1996023377A1 Multimedia system having central power source and distribution subsystem
08/01/1996DE19508226C1 Over-load protection for remote power supply of communication terminal
07/1996
07/31/1996EP0724348A1 Method and circuit for failsafe stitch-hook detection during fault in a telephone system
07/31/1996EP0724347A2 Power-outlet mount for a portable telephone
07/30/1996US5541543 Regulating device for a telephone loud-speaker
07/23/1996US5539821 Power outlet mount for a portable telephone
07/23/1996US5539805 Power supply system including ringing voltage reset under low input voltage conditions
07/18/1996DE19519881C1 Battery charging device for cordless telephone
07/18/1996DE19500167A1 Portable telecommunication appts. with acousto-electrical acoustic transducer
07/16/1996US5537657 Telecommunications device with means for learning and responding to a distinctive ring cadence
07/11/1996WO1996021316A1 Generation of a ringing signal
07/11/1996DE19526220A1 Signalling device for telecommunications terminal
07/10/1996EP0425675B1 Ground fault detecting circuit for subscriber lines
07/10/1996CN1126533A Front end processor employing data over voice communication with smart telephones
07/09/1996US5535273 Circuitry for superimposing small, low energy signals and large, essentially higher energy signals
07/09/1996US5535272 Sensor circuit for a telephone line
07/04/1996DE4445804A1 Switching of telecommunication links through switch matrix of exchange
07/03/1996EP0719488A1 Power supply controller for an optical fibre telecommunications system
07/03/1996EP0719439A1 Voice activity detector
06/1996
06/27/1996WO1996019890A1 Method and system for controlling access to a channel
06/26/1996EP0719029A2 Battery feed circuit
06/26/1996EP0719022A2 Communication terminal equipment and method of signifying incoming call
06/26/1996EP0519963B1 Telephone call detecting circuit and a method of remotely accessing and testing a telephone
06/25/1996US5530931 Method and apparatus for providing a look ahead feature for enhanced call forwarding in a telecommunications system
06/25/1996US5530748 Power supplying system for terminal
06/25/1996US5530743 Telephone exchange apparatus and tone sending method in telephone exchange apparatus
06/23/1996CA2165591A1 Isolated high impedance, dc current sources for telecommunications applications
06/20/1996CA2161170A1 Battery feed circuit
06/19/1996CN1125025A A home and small business phone system for operation on a single internal twisted pair line
06/18/1996US5528697 Integrated vibrating and sound producing device
06/18/1996US5528688 Telephone battery feed circuit including noise reduction circuit
06/18/1996US5528686 Transformerless hybrid circuit having direct powered line-side amplifiers
06/18/1996US5528682 Double duty capacitor circuit and method
06/14/1996CA2163570A1 Method and apparatus for detecting a telephone cpe alerting signal
06/12/1996EP0628231B1 Analogue bidirectional switch
06/11/1996US5526418 Ringer circuit
06/05/1996DE19512167C1 Telecommunication system with gateway speech terminal
06/04/1996US5524061 Dual mode transducer for a portable receiver
05/1996
05/28/1996US5521964 Visual message waiting indication in a telephone voice message system
05/23/1996WO1996015617A1 Supply voltage switching apparatus
05/23/1996WO1996015614A1 Independent volume control for multi-system radio telephone
05/23/1996WO1996015611A1 Automated audio output device for a telephone set
05/23/1996WO1996015592A1 Driving stage
05/23/1996CA2204873A1 Driving stage
05/22/1996EP0713343A2 Portable multi-information communication device
05/22/1996EP0713320A1 Ring generator circuit
05/21/1996US5519775 Device for electrical and/or electronic telephone circuits, designed to limit the power dissipated within them
05/14/1996US5517565 Integrated ringer relay circuit and method
05/14/1996US5517547 Alarm panel with cellular telephone backup
05/07/1996US5515434 Impedance setting circuit for a SLIC
05/07/1996US5515433 For use with a telecommunication line
05/07/1996US5515417 Ground key detector for a SLIC
05/02/1996WO1996013114A1 Method and apparatus for providing a look ahead feature for enhanced call forwarding in a telecommunications system
05/01/1996EP0710000A1 Power supply apparatus for a telecommunication terminal
05/01/1996EP0709812A2 Signalling receiver with alarm selecting facility
05/01/1996EP0709010A1 Power coupler for coupling power from a transmission line to a node thereon
04/1996
04/30/1996US5513059 Arrangement for protecting telecommunications equipment from voltage transients
04/25/1996WO1996012196A1 Method for detecting a signal
04/24/1996EP0708575A2 ISDN network termination
04/24/1996EP0707770A1 Dial in-bound meter interface unit which derives its power from a telephone line
04/23/1996US5511118 Method of providing d.c. feed to a telephone line
04/16/1996US5509069 Splitting of a supply current drawn from a telecommunication system's line among a plurality of user's circuits
04/16/1996US5509068 Electronic ring monitoring device for telecommunications line
04/11/1996WO1996010859A1 Electrical switching and control arrangement
04/11/1996DE4435978A1 Power management and network control for ISDN telephone appts
04/11/1996DE4435053A1 Electrical switching and control installation
04/11/1996DE4435006A1 Electrical switching and control installation
04/10/1996CN1120381A Power supply controller for an optical fibre telecommunications system
04/10/1996CN1120275A Integrated interface circuit for driving a subscriber line
04/04/1996DE19504480C1 Integratable HV switch, e.g. SLIC
04/03/1996EP0705020A2 Circuit arrangement for feeding at least a load
03/1996
03/28/1996WO1996009711A1 Method and apparatus for determining the deviation of longitudinal signal components from a predetermined value
03/28/1996CA2200178A1 Method and apparatus for determining the deviation of longitudinal signal components from a predetermined value
03/27/1996EP0703695A1 Line impedance synthesis circuit
03/19/1996US5500896 Code converter comprising protection circuit
03/19/1996US5500895 Telephone isolation device
03/19/1996US5500893 Telephone apparatus, information processing apparatus and information communication terminal
03/14/1996DE4432214A1 Low-loss generation of DC and AC voltages e.g. for telephone subscriber connections
03/07/1996DE4416592A1 Analogue telephone equipment arrangement for connection to personal computer
02/1996
02/29/1996DE4429840A1 Choke coil action simulation using gyrator
02/28/1996EP0698988A1 Circuit arrangement with at least a stage to be supplied from a voltage source
02/28/1996CN1117701A Cordless telephone apparatus
02/27/1996US5495530 Low power emergency telephone mode
02/22/1996WO1996005684A1 Improved communications marketing system
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