Patents
Patents for H04M 19 - Current supply arrangements for telephone systems (7,475)
02/1996
02/20/1996US5493611 User configurable telephone with alarm feature
02/20/1996CA2040327C Isdn (intergrated services digital network) interface circuit and system using the same
02/13/1996US5491746 Unique ringing on a prime telephone
02/13/1996CA2067884C Subscriber apparatus
02/08/1996WO1996003811A1 Power consumption control method and apparatus for a communication system subscriber unit
02/08/1996DE19526610A1 Call signal recognition appts. for modem activation
02/07/1996EP0696122A2 Fault current protection device for an auxiliary apparatus in digital telephone installation
02/07/1996CN1030951C Current limited subscriber interface circuit
02/06/1996US5490054 Ringing generator and method for converting DC to AC having continuously adjustable amplitude
02/01/1996WO1996002999A1 Recordable voice/sound ringer for telephone
01/1996
01/31/1996CN1116019A Direct-current impressing circuit
01/30/1996CA2134787C Digital controlled ringer signal generation
01/24/1996EP0693850A1 Independent telephone power supply
01/24/1996EP0693846A2 Telephone subscriber line interface circuit and method
01/24/1996EP0693238A1 A home and small business phone system for operation on a single internal twisted pair line
01/18/1996DE4425824A1 Fully electronic, one-pole switch for DC or AC voltages
01/16/1996US5485516 Line termination for a telephone line
01/16/1996CA2063205C Key telephone system
01/16/1996CA2062526C Subscriber line interface circuit for serving isdn subscribers using echo cancellers and pots subscribers
01/10/1996EP0691752A1 Transformerless hybrid circuit having direct powered line-side amplifiers
01/09/1996US5483592 Ringer unit driving system in a subscriber transmission system
01/09/1996US5483574 Communication terminal equipment
01/04/1996WO1996000429A1 Paging receiver with distinctive alert patterns
01/04/1996DE4423790A1 Operating installation for additional powered function via telephone exchange line
01/04/1996DE19522769A1 Device for transmitting information to an interested party
01/03/1996EP0690563A2 Output circuit having at least one external transistor
01/02/1996US5481599 Automated audio output device for a telephone set
12/1995
12/27/1995CN1114094A Low internal feed equipment for subscriber's interface
12/26/1995US5479476 Mobile telephone having groups of user adjustable operating characteristics for facilitating adjustment of several operating characteristics
12/26/1995US5479056 Power source device
12/26/1995CA2077522C Battery feed circuit for supplying feed current to telephone set
12/20/1995EP0688125A1 Mobile phone with vibrating alarm
12/20/1995EP0688082A1 Portable communication apparatus preventing trouble when battery wears
12/14/1995WO1995034123A1 Asymmetrical low frequency modulation switching inverter
12/13/1995EP0687098A2 Telephone line sourced power supply
11/1995
11/23/1995DE4417387A1 Emergency operation procedure for speech and/or data communication appts. in digital ISDN and analog telephone network
11/22/1995EP0683593A2 Energy saving mode in telecommunications equipment
11/22/1995EP0630543B1 Circuit for transmitting small, low energy signals and large, essentially higher energy signals
11/22/1995CN1030365C Telephone circuit assembly with hook-off detector circuit
11/21/1995US5469282 Power supply system for optical network unit of a fiber in the loop
11/15/1995CN1111885A Portable alerting unit for alerting a user to call arrival to portable radio apparatus
11/14/1995US5467384 Method and apparatus for providing power to a coaxial cable network
11/08/1995EP0681389A2 Telephone line interface circuit
11/08/1995EP0681388A2 Telephone line interface circuit
11/08/1995CN1111471A Electronic device having internal charge regulator
10/1995
10/26/1995WO1995028793A1 Power management for line powered telecommunication apparatus
10/26/1995CA2187452A1 Power management for line powered telecommunication apparatus
10/25/1995EP0679009A2 Switching device with feeding circuit for providing the current to a subscriber terminal
10/25/1995CN1110886A Standby power saving in mobile phones
10/24/1995US5461671 Telephone line power utility circuit
10/24/1995CA2035411C Ringing circuit for use in portable telephone set
10/18/1995CN1110494A Method and apparatus for providing power to a coaxial cable network
10/17/1995US5459783 Acoustic feedback suppression device particulary for auxiliary ringers in plug-in telephone systems
10/12/1995DE4420430C1 Supplying operating voltage to subscriber line connections at exchange
10/11/1995EP0676862A1 Direct-current impressing circuit
10/11/1995EP0569582A4 Telephone ringing signal generator
10/10/1995US5457741 Subscriber transmission system
10/10/1995CA1337305C High impedance signal detection device
10/05/1995DE4409394C1 Telephone appts. call tone signal radiating system
10/04/1995EP0675629A1 Method for faultless off-hook detection in ring signal feeding in a digital telephone exchange and circuit for the implementation of the same
10/03/1995US5455466 Inductive coupling system for power and data transfer
09/1995
09/27/1995EP0674417A2 Call alerting auxiliary device for a portable radiotelephone
09/26/1995US5454032 Method of establishing communication link to one of multiple devices associated with single telephone number
09/26/1995US5454031 Dial inbound meter interface unit which derives its power from a telephone line
09/21/1995DE4408324A1 Kompakt-Fernsprechendgerät Compact telephone terminal
09/20/1995EP0673146A1 Method for assigning of ring signal units arranged in pairs in a multiple time division telephone exchange
09/19/1995US5452354 Ringing tone apparatus
09/14/1995WO1995024790A1 Compact telephone set
09/13/1995EP0671098A1 Network termination unit
09/12/1995US5450618 Full duplex and half duplex communication unit with volume setting
09/12/1995US5450613 Mobile communications equipment which detects and notifies when it is moved into or out of a service area
09/06/1995EP0670651A1 Circuit arrangement for DC-feeding of a telephone line
09/05/1995US5448620 Volume control for a dual mode communications device
08/1995
08/31/1995DE4427207C1 Fault current protection device for digital telephone accessory
08/31/1995DE4406500A1 Circuit for low-loss AC voltage generation
08/30/1995EP0669750A2 Call detecting circuit in a telecommunication terminal
08/29/1995US5446785 Telephone terminal equipment in which telephone numbers of callers are displayed
08/29/1995CA2034094C Radio telecommunication apparatus
08/24/1995DE19502152A1 Anzeigeschaltung für Telefonanrufe Ads for phone calls
08/23/1995EP0668688A1 Network connecting equipment and concentrator connecting equipment in a telecommunication network
08/23/1995EP0668685A1 Circuit arrangement for backing-up data upon a power failure for an answering device with digital voice storage in telecommunication terminals
08/23/1995EP0668001A1 Process for programming a base station using a mobile unit.
08/22/1995US5444777 Battery feed for telephone line cards
08/17/1995DE4404509A1 Additional call member arrangement for telephone subscriber's appts.
08/16/1995EP0667084A1 Information transmission system
08/16/1995EP0667079A1 Process for charging accumulators in cordless communications equipment
08/15/1995US5442695 Ringer circuit
08/15/1995US5442694 Ring tone detection for a telephone system
08/15/1995US5442692 Telecommunication system having a capability of changing the alerting tone
08/10/1995WO1995021485A1 Power supply for private branch exchange
08/10/1995WO1995019083A3 Interface circuit
08/09/1995EP0593556A4 Telephone marketing system.
08/08/1995US5440595 Communication apparatus with low power consumption
08/08/1995US5440262 High-efficiency Ring/MWL generator
08/08/1995US5440253 Semiconductor integrated comparator circuit
08/01/1995CA2041209C Tone and announcement message code generator for a telephonic switching system and method
07/1995
07/27/1995WO1995020290A1 A method and an arrangement for generating a ringing signal
07/27/1995WO1995020289A1 A method for off-hook detection during ringing and the use of a subscriber line interface circuit for off-hook detection during ringing
07/27/1995CA2179995A1 A method for off-hook detection during ringing and the use of a subscriber line interface circuit for off-hook detection during ringing
07/27/1995CA2179387A1 A method and an arrangement for generating a ringing signal
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