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)
03/1985
03/19/1985US4506112 Telephone set including a circuit for seizing the line without lifting the handset off the gravity switch
03/12/1985US4504701 Telephone having circuitry for reducing the audio output of the ringing signal
03/05/1985US4503291 Repertory dialer with efficient data storage
03/05/1985US4503289 Line circuit with flux compensation and active impedance termination
02/1985
02/26/1985US4502139 Howler tone sending-out system in time-division electronic exchanges
02/26/1985US4501933 Transistor bridge voltage rectifier circuit
02/19/1985US4500844 Ringing signal generator employing delta-modulation power amplification techniques
02/13/1985EP0133100A1 Ring injection circuit for a subscriber set
02/12/1985US4499532 Floating battery feed circuit
01/1985
01/29/1985US4496798 Ringing circuit for telephone subset, designed as an integrated circuit
01/22/1985US4495652 Control arrangement for radio apparatus
01/09/1985EP0130553A2 Improvements in telephone instruments
01/09/1985EP0130261A1 D.C. powering circuit for a line interface circuit
01/08/1985US4492821 Subscriber connection circuit
01/01/1985US4491700 Hybrid circuit in a telephone subscriber interface circuit
01/01/1985US4491691 Electronic tone ringer
12/1984
12/27/1984CA1180140A Electronic tone ringer
12/25/1984US4490580 Subscriber line circuit comprising a controllable DC/DC converter as a battery feed circuit
12/18/1984US4489222 Telephone line interface
12/11/1984US4488006 Apparatus for controlling the application of telephone line power in a telephone set
12/06/1984WO1984004857A1 Ringing signal generator
12/04/1984US4486879 Method and apparatus for mixing low-frequency signals transmitted via different time slots towards the same telephone receiver set
12/04/1984CA1179080A1 Tone ringer for telephone sets and other telecommunications apparatus
12/04/1984CA1179079A1 Power supply control circuit for subscriber carrier telephone system
12/04/1984CA1179078A1 Active impedance line feed circuit
12/04/1984CA1179004A1 Energy distribution device
11/1984
11/28/1984EP0126137A1 Apparatus for providing tone signals in terminals for a digital telecommunnication system
11/20/1984US4484032 Active impedance transformer assisted line feed circuit
11/20/1984US4484028 Digital loop transceiver having a power up/down circuit
11/20/1984CA1178386A1 Active impedance transformer assisted line feed circuit
11/20/1984CA1178353A1 Remote supply circuit for an analog two-wire connection
11/14/1984EP0125012A1 Tone source for telephone systems
11/13/1984CA1177986A1 Balanced current multiplier circuit for a subscriber loop interface circuit
11/13/1984CA1177985A1 Electronic terminator circuit
11/06/1984US4481463 Current mirror circuit
10/1984
10/30/1984US4480154 Automatic telephone silencer
10/24/1984EP0122354A2 Telephone exchange
10/23/1984US4479034 Control system for a telephone switching system
10/23/1984CA1176706A1 Telephone line circuit
10/16/1984US4477697 Method and circuitry for encoding telephone ringing signals
10/09/1984US4476351 Subscriber loop current regulator
10/09/1984US4476350 Battery feed circuit
10/09/1984CA1175966A1 Subscriber line interface circuit
10/09/1984CA1175898A1 Current supply circuit
10/02/1984CA1175587A1 Overvoltage protection for a line circuit
10/02/1984CA1175501A1 Arrangement for exchanging signals between separated circuit arrangements
10/02/1984CA1175488A1 Power supply control circuit for subscriber carrier telephone system
09/1984
09/27/1984WO1984003809A1 Floating battery feed circuit
09/26/1984EP0119678A1 Tone generator
09/26/1984EP0119422A2 Inductance simulation circuit
09/26/1984EP0119245A1 Arrangement for supplying current to a subscriber telephone set.
09/26/1984EP0119234A1 Apparatus for the current supply of a subscriber set from an exchange.
09/25/1984US4473719 Switchhook status detector
09/19/1984EP0119163A2 Method and arrangement for information transmission via the low-voltage electrical power distribution network, and its use
09/19/1984EP0118545A1 Pulse width modulated telephone line interface
09/18/1984US4472608 Subscriber line interface circuit
09/18/1984US4472602 Telephone set with transducer/ringer
09/11/1984US4471169 Arrangement of interactive telephone switching processors and associated port data storage means
09/11/1984CA1174390A1 Pulse width modulated voltage converter
09/04/1984CA1173902A1 Standby power unit
08/1984
08/30/1984WO1984003408A1 Method and circuitry for encoding telephone ringing signals
08/30/1984WO1984003405A1 Electronic tone ringer
08/29/1984EP0116767A2 Battery feed circuit for a telephone subscriber line
08/28/1984CA1173578A1 Subscriber line interface circuit with impedance synthesizer
08/28/1984CA1173577A1 Electronic subscriber line interface circuit
08/22/1984EP0116291A2 Ring trip detection system
08/21/1984US4467310 Telephone subscriber line battery feed resistor arrangements
08/21/1984US4467269 Start-up circuit for negative inductance multiplier
08/21/1984US4467144 Telephone annuciator extender
08/21/1984CA1173182A1 Programmable line circuit
08/16/1984WO1984003191A1 Borsht/slic auto balancing technique
08/14/1984US4465967 Current supply circuit
08/14/1984US4465903 Electronic telephone interface circuit
08/14/1984CA1172737A1 Analog subscriber/trunk module with shared ringing source and ring trip
08/01/1984EP0066577B1 Pulse with modulated voltage converter for generating a preferably sinusoidal alternating voltage
07/1984
07/31/1984US4463307 Negative inductance multiplier circuit including temperature compensation
07/31/1984CA1171989A1 Battery feed circuit
07/31/1984CA1171922A1 Solid state relay
07/25/1984EP0113747A1 A method for current supply to a subscriber telephone from a telephone exchange.
07/10/1984US4459435 Telephone privacy apparatus
07/04/1984EP0112731A2 Subscriber line interface circuit
07/03/1984US4458112 Floating subscriber loop interface circuit
07/03/1984US4458111 Charging and discharging circuit
07/03/1984CA1170381A1 Subscriber drop circuit for controlling drop current with load and maximizing power usage
06/1984
06/19/1984US4455456 Digital supervisory circuit for a telephone system
06/13/1984EP0110444A1 Ringing signal generator
06/07/1984WO1984002240A1 Apparatus for providing tone signals in terminals for a digital telecommunnication system
05/1984
05/30/1984EP0109705A1 Subscriber circuit for a telephone network
05/29/1984US4451773 Rectifier control system for a DC power plant system
05/29/1984US4451703 All electronic interface for telephony system
05/29/1984US4451702 Arrangement of interactive telephone switching processors for performing timing analyses of port events
05/08/1984US4447675 Ring-trip detector
05/08/1984US4447673 Ring trip apparatus for a line circuit connected to DCO switch
05/08/1984CA1167101A1 Current limiting circuit
05/02/1984EP0107133A1 Circuit for powering a feeding device delivering a constant working voltage
05/02/1984EP0107074A1 Process for the suppression of quantification noise superposed on a sinusoidal audible tone at the transmission in a digital telecommunication exchange
05/02/1984EP0106848A1 Circuit for a coin-operated telephone apparatus
05/01/1984US4446340 Customer premises loop test unit powered from the normal central office power source
05/01/1984US4446339 Rotary dial decoder
04/1984
04/25/1984EP0106247A1 Telephone system
1 ... 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75