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)
02/1997
02/06/1997WO1997004618A1 Electronic driver for an electromagnetic resonant transducer
02/06/1997WO1997004574A2 Telephone exchange
02/04/1997US5600713 On-board ring signal generator
02/04/1997CA2059055C High voltage converter
01/1997
01/29/1997EP0756413A1 Ring trip circuit having a simple trip detecting circuit of a high response speed
01/29/1997EP0756409A1 Spurious ting suppression device particularly for auxiliary ringers in socket telephone systems
01/29/1997EP0755603A1 Power management for line powered telecommunication apparatus
01/29/1997CN1141706A Method and system for controlling access to a channel
01/29/1997CN1141705A Clear channel selection system for cordless telephone
01/28/1997US5598461 Personalized annunciation signaling phone unit
01/28/1997US5598327 Planar transformer assembly including non-overlapping primary and secondary windings surrounding a common magnetic flux path area
01/22/1997CN2245833Y Constant-current constant-pressure feeding amplifying device
01/21/1997US5596637 Power dissipation manager circuit for an interface device feeding a subscriber telephone line
01/21/1997US5596470 Fault current protection circuit for an auxiliary device in a digital telephone system
01/21/1997CA2106342C Alert method for cordless telephones
01/16/1997WO1997001916A1 Telephone ring detector
01/14/1997US5594785 Method of producing ring-back tone in order wire
01/14/1997CA2068154C Programmable call progress tones for a switching system
01/09/1997DE19621439A1 Verfahren zur Leistungssteuerung und Vorrichtung für die Verwendung in einer Funkkommunikationsvorrichtung A method for controlling power and apparatus for use in a radio communication device
01/08/1997EP0752182A1 Method and system for controlling access to a channel
01/07/1997US5592475 Distributed digital loop system with trunk unit interface
01/02/1997EP0751660A1 Method for determination of proper remote feeding of communication terminals connected to a communication system
01/01/1997CN1139505A Method for off-hook detection during ringing and the use of a subscriber line interface circuit for off-hook detection during ringing
12/1996
12/27/1996WO1996042162A1 Telephone line interface circuit
12/27/1996EP0749654A1 Compact telephone set
12/27/1996CA2197337A1 Telephone line interface circuit
12/25/1996CN1138790A 自举电源 Bootstrap supply
12/25/1996CN1033681C Communications device
12/19/1996WO1996041439A1 Standby power saving in mobile phones
12/18/1996EP0749229A2 Signal coupling circuit in a telephone set
12/18/1996EP0550554B1 Circuit protection device
12/18/1996CN1138399A A method and an apparatus for generating a ringing signal
12/18/1996CN1138254A Power control method and apparatus suitable for use in radio communication device
12/11/1996EP0748106A2 Telecommunication device with an additional apparatus
12/11/1996EP0748104A2 Communication apparatus
12/10/1996US5583934 DC level control for an electronic telephone line card
12/10/1996CA2091278C Unique ringing on a prime telephone line
12/04/1996EP0746131A1 Radio communication apparatus
12/04/1996EP0746128A1 Telephone interface circuit with impedance termination during call pauses
12/03/1996US5581612 Private branch exchange system
11/1996
11/27/1996EP0744855A2 Subscriber line interface and power circuit
11/27/1996CN1136753A Selective incoming call receiving method in telephone system
11/27/1996CN1136743A Relay circuit and method of integrated signalling set
11/27/1996CN1136742A Security hook key detecting method and circuit in fault period of telephone system
11/27/1996CN1136733A Portable power socket device
11/26/1996US5579535 Personal communication system providing supplemental information mode
11/26/1996US5579386 Telephone network alerting cadence control system
11/21/1996DE19521135C1 Radio telephone with solar-powered battery
11/20/1996CN2240814Y Active feed interface device
11/20/1996CN1136261A Audible tone signal service apparatus and method of digital mobile services switching center
11/19/1996US5577104 Method for system and message activation based on distinctive ringing
11/14/1996WO1996036156A1 T1 channel bank control process and apparatus
11/14/1996WO1996036112A1 Isolating circuit for telephone apparatus
11/12/1996US5574772 Personal apparatus for receiving radiotelephone communications
11/12/1996CA2098136C Remote charging cradle for cordless telephone handset
11/12/1996CA2040476C Facsimile apparatus comprising cordless telephone set
11/06/1996EP0740881A1 A method and an arrangement for generating a ringing signal
11/06/1996EP0740880A1 A method for off-hook detection during ringing and the use of a subscriber line interface circuit for off-hook detection during ringing
11/06/1996CN1135136A Telephone subscriber line interface circuit and method
10/1996
10/30/1996EP0740449A2 Portable telephone set
10/30/1996EP0636297B1 Subscriber line interface circuit with voltage controlled loop current
10/30/1996EP0636296B1 Impedance synthesizer for a subscriber line interface circuit
10/29/1996US5570421 Call informing device
10/29/1996US5570025 Annunciator and battery supply measurement system for cellular telephones
10/29/1996US5570003 Switching device with a feeding circuit for DC power supply to a subscriber's terminal unit
10/24/1996DE19532156C1 DC voltage supply circuit for two-wire connection to telephone communication appts.
10/23/1996EP0738445A1 Clear channel selection system for a cordless telephone
10/23/1996CN1134096A Radiotelephone having plurality of subscriber identities and method for operating same
10/22/1996US5568547 Subscriber circuit provided with a circuit for monitoring a subscriber instrument
10/22/1996US5568513 Standby power savings with cumulative parity check in mobile phones
10/17/1996WO1996032799A1 Communication device
10/16/1996EP0738066A2 Integrated ringer for short telephone lines
10/08/1996CA2088629C Ringing tone signal detecting circuit
10/08/1996CA2088420C Method of establishing communication link to one of multiple devices associated with single telephone number
10/02/1996EP0735737A2 Communication system with a terminal designed as a door telephone
10/02/1996EP0410978B1 Animated data display interleaving
10/02/1996CN1132433A Telephone battery feed circuit including noise reduction circuit
10/01/1996US5561704 Proximity based toll free communication services
10/01/1996CA2104406C Bell signal generating circuit
10/01/1996CA2063223C Power and signal transmission system
09/1996
09/25/1996EP0733296A1 Digital rural subscriber concentrator system
09/24/1996CA2076976C Private telephone system with simplified command feature
09/19/1996WO1996028922A1 Battery pack for portable radio-pagers or radio-telephones, in particular cellular telephones
09/18/1996CN1131365A Ringtrip judging circuit
09/18/1996CN1131363A Communication terminal equipment and call incoming control method
09/17/1996US5557658 Communications marketing system
09/12/1996WO1996027998A1 Telecommunication system
09/12/1996WO1996027974A1 A telephone set having calling party dependent ringing
09/12/1996WO1996027970A1 Dc level control for an electronic telephone line card
09/12/1996DE19507656A1 Telekommunikationssystem Telecommunications system
09/12/1996CA2214777A1 A telephone set having calling party dependent ringing
09/11/1996CN1130952A 语言活动性检测器 Language activity detector
09/10/1996US5555301 Power supply apparatus and method for energizing telephone alerting mechanisms and circuitry
09/10/1996CA2078041C Ring trip detection circuit
09/06/1996WO1996027253A1 Incoming-call vibrator
09/05/1996DE19506907A1 Voltage or current level input signal changing circuit for e.g. EEPROM
09/03/1996US5553138 Telephone line sourced power supply
09/03/1996US5553132 Method and an arrangement for generating a ringing signal
09/03/1996US5553125 Telephone apparatus with calling line identification
08/1996
08/28/1996EP0729259A1 Ring-signal generation in a slic
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