H04M 19 - Current supply arrangements for telephone systems

Patents for H04M 19 - Current supply arrangements for telephone systems (7,475)
11/1994
11/29/1994	US5369518 Optical communication system and method electrical power transmission for thereof
11/29/1994	CA2173003A1 Method and apparatus for delivering secured telephony service to a hybrid coaxial cable network
11/26/1994	CA2096882A1 Ringmaster
11/24/1994	WO1994027377A1 Standby power saving in mobile phones
11/24/1994	CA2139770A1 Standby power saving in mobile phones
11/22/1994	US5367567 Subscriber apparatus with ringer generator for sending ringer signal to subscriber line
11/22/1994	US5367447 Signal separation circuit
11/22/1994	CA2025014C Ground fault detector
11/22/1994	CA1333189C Protection circuit for battery feed circuit
11/08/1994	US5363431 Visual message waiting indication in a telephone voice message system
11/02/1994	EP0622943A1 Power management circuit for a subscriber line interface circuit
11/02/1994	EP0622932A2 Telecommunication terminal apparatus comprising a vibration generator for tactile alerting
11/01/1994	US5361300 Balancing resistor and thermistor network for telephone circuits, and combination thereof with relay
10/1994
10/27/1994	WO1994024805A1 Alarm panel with cellular telephone backup
10/26/1994	CN1026376C Circuits arrangement for producing of alternating voltage
10/25/1994	US5359655 Supply circuit for a telecommunication line, providing highly symmetrical and rapid response to line voltage disturbances
10/25/1994	US5359650 Digital circuit for conditional initialization
10/14/1994	CA2081040A1 Alarm panel with cellular telephone backup
10/13/1994	WO1994023508A1 A home and small business phone system for operation on a single internal twisted pair line
10/11/1994	US5355401 Method and apparatus for providing telephony power through a coaxial cable network
10/11/1994	CA1332479C High impedance signal detection device
10/06/1994	DE4310601A1 Charging unit for the spare battery of the mobile part of a cordless telephone
10/06/1994	DE4310599A1 Retaining and closing device for the battery of a mobile telephone in the charging unit
09/1994
09/29/1994	WO1994022254A1 Connecting device
09/21/1994	EP0616460A1 Interface device between a public telephone and an external terminal
09/21/1994	EP0548069B1 Speaker drive arrangement for loudspeaker telephone
09/14/1994	EP0615375A2 Subscriber line interface circuit
09/14/1994	EP0615371A2 Audio output equipment for a portable telephone
09/13/1994	US5347577 Battery feed circuit for supplying feed current to telephone set
09/13/1994	US5347565 Order wire device having function for reducing noise in communication system having a plurality of order wire devices
09/13/1994	US5347417 Power supply protection system applied to optical subscriber network
09/08/1994	DE4307612A1 Arrangement for supplying power to cordless communications terminals
09/01/1994	WO1994019896A1 Telelphone dialling code processor
08/1994
08/31/1994	EP0527142B1 Line interface circuit with active tip and ring feed means
08/31/1994	EP0323516B1 Ring trip circuit for subscriber telephone
08/30/1994	US5343520 Impedance synthesis multile loop using filtering means
08/30/1994	US5343084 Variable level periodic excitation circuit for a capacitive load
08/30/1994	CA2024213C Telephone terminal device
08/24/1994	EP0536183B1 Line interface circuit
08/23/1994	US5341108 Amplifier biasing circuit
08/17/1994	EP0611070A2 Mobile telephone
08/10/1994	CN1025648C Coupling device to be connected to a DCE for the connection to a public switched telephone network having a local power supply circuit for allowing the use of the local telephone,......
08/09/1994	US5337356 Ringing circuit for use in portable telephone set
08/09/1994	US5337355 Supply circuit device for a user's telephone circuit, having a low voltage loss
08/09/1994	US5337354 Tip-ring voltage correction circuit
08/04/1994	WO1994017619A1 Method of providing d.c. feed to a telephone line
08/02/1994	US5335272 Method and arrangement for supplying direct current to a telephone line
08/02/1994	US5335271 Ring trip detection circuit
08/02/1994	US5335270 Bell signal generating circuit
08/02/1994	CA2024941C Composite ringing and coin control voltage detector and method
08/02/1994	CA2009164C Telephone having touch sensor for responding to a call
07/1994
07/27/1994	EP0608077A2 Resistor network including telephone circuits
07/27/1994	CN1090111A Anti-saturation exchanger port inductive circuit
07/26/1994	US5333196 For a telephone subscriber loop
07/26/1994	US5333192 Line interface circuit
07/26/1994	US5333190 Telephone ring detection method and apparatus
07/26/1994	CA2023789C Apparatus and method for encoding telephone ringing signals
07/21/1994	DE4310600C1 Support mounting for cordless or mobile telephone handset
07/13/1994	CN1025469C Power system for telephony system
07/12/1994	US5329588 Telecommunication line circuit
07/12/1994	US5329585 Subscriber line interface circuit for controlling AC and DC output impedance
07/12/1994	US5329584 Interface circuit to quickly establish a loop current
07/12/1994	US5329577 Telephone having touch sensor for responding to a call
07/07/1994	WO1994015415A1 Optical communication system and method
07/06/1994	CN1025406C Line interface circuit
07/05/1994	US5327482 Public cordless telephone system with coin/card insertion inhibiting means
06/1994
06/29/1994	EP0604081A1 Ringing tone appartus
06/29/1994	CN1025270C Interface circuit
06/23/1994	DE4342491A1 Telephone line sensor circuit
06/22/1994	EP0602894A2 Apparatus for electrically isolating a telephone line from a data device
06/21/1994	US5323461 Telephone line interface circuit with voltage switching
06/21/1994	US5323460 Enhanced subscriber line interface circuit
06/21/1994	US5323456 Digitally controlled ringer signal generation
06/21/1994	US5323455 Ringer circuit, particularly for a telephone set
06/21/1994	US5323453 Power down feed
06/18/1994	CA2111038A1 Apparatus for electrically isolating a telephone line from a data device
06/15/1994	EP0601539A2 Communication apparatus with low power consumption
06/15/1994	CN1025101C Overvoltage and overcurrent protective circuit with high earth balance
06/14/1994	US5321740 Telephone marketing system
06/14/1994	US5321596 DC/DC/AC power supply for a subscriber interphase unit
06/09/1994	WO1994013090A1 Network termination unit
06/09/1994	WO1994013065A1 Aural annunciator circuit for a receiver
06/08/1994	EP0600644A1 Ring-trip detection using ring voltage and current
06/08/1994	EP0600175A1 Subscriber line interface circuit for controlling AC and DC output impedance
06/08/1994	EP0409844B1 Amplifier arrangement and communication line circuit using same
06/01/1994	DE4306251C1 Telecommunication system user connection line circuitry - indicates status of telephone user connection line according to call signal which switches transistor connected to operational amplifier inputs
06/01/1994	DE4239943A1 Telephone for people hard of hearing - has externally powered amplifier for speech signal and frequency controllable bell
05/1994
05/31/1994	US5317634 Telephone subset arrangement
05/31/1994	US5317622 Ringing circuit for use in a telephone set for detecting a mobile mode or a portable mode of the telephone set
05/31/1994	US5317545 Telephone timer apparatus
05/24/1994	US5315653 Current limited subscriber interface circuit
05/24/1994	US5315652 Terminal for telegraph and telephone systems
05/19/1994	DE4237394A1 Mains power unit esp. for cordless telecommunication equipment - supplies battery-recharging DC from bridge rectifier via pre-regulating series thyristor circuit and output voltage stabiliser
05/17/1994	US5313661 Method and circuit arrangement for adjusting the volume in a mobile telephone
05/11/1994	WO1994010809A1 Information transmission system
05/11/1994	WO1994010786A1 Process for programming a base station using a mobile unit
05/11/1994	WO1994010782A1 Process for charging accumulators in cordless communications equipment
05/10/1994	US5311518 ISDN interface circuit and system using the same
05/05/1994	DE4237153A1 Telephone subscriber circuitry supplied from exchange battery - with current or voltage evaluation circuit controlling switch for charge storage capacitor connected to one supply terminal
05/05/1994	DE4236725A1 Telephone subscriber's appts. with call indication - activates stored tone sequence upon incoming call until call is picked up

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