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)
04/1984
04/24/1984US4445006 Four-wire conversion circuit for a telephone subscriber line
04/24/1984CA1166373A1 Communications system connecting circuit
04/17/1984US4443669 Subscriber connection circuit
04/17/1984US4443663 Filtering of port data in a switching system employing interactive processors
04/17/1984CA1165916A1 Electronic subscriber junctor
04/17/1984CA1165915A1 Programmable ring signal generator
04/11/1984EP0105184A1 Circuit for decreasing the noise voltages due to longitudinal currents
04/04/1984EP0104581A2 Loop current feeding for a signalisation signal convertor
04/04/1984EP0104220A1 Supply circuit included in a dc-magnetized hybrid transformer.
04/03/1984US4440980 For applying current in two directions to one wire
03/1984
03/29/1984WO1984001250A1 Arrangement for supplying current to a subscriber telephone set
03/29/1984WO1984001249A1 Apparatus for the current supply of a subscriber set from an exchange
03/29/1984WO1984001248A1 Pulse width modulated telephone line interface
03/27/1984CA1164593A1 Device for powering a subscriber set
03/27/1984CA1164592A1 Telephone line feed
03/13/1984US4436961 Communications system connecting circuit for controlling derivation of operating power from subscriber line current
03/13/1984US4436960 Telephone ringing signal generator
03/07/1984EP0102111A2 Telephone circuit
03/06/1984US4435803 Telephone signaling system
03/06/1984CA1163390A1 Voltage stabiliser suitable for use in a telephone set
03/06/1984CA1163389A1 Voltage stabiliser suitable for a telephone set
02/1984
02/21/1984US4433213 Subscriber's line circuit for telecommunications networks
02/15/1984EP0100514A2 Device for detecting looping during ringing
02/14/1984US4431874 Balanced current multiplier circuit for a subscriber loop interface circuit
02/14/1984US4431871 Solid state relay
02/14/1984US4431869 Telephone line feed
02/14/1984US4431868 Solid state telephone line interface circuit with ringing capability
02/14/1984CA1162337A1 Digital tone ringer
02/02/1984WO1984000459A1 A method for current supply to a subscriber telephone from a telephone exchange
01/1984
01/31/1984US4429186 Floating battery feed circuit for telephone subscriber line interface
01/31/1984US4429185 Voltage detector circuit
01/31/1984CA1161506A1 Precision negative impedance circuit with calibration
01/25/1984EP0099156A2 Power supply arrangement for applying direct current to subscriber circuits
01/19/1984WO1984000270A1 Apparatus for controlling the application of telephone line power in a telephone set
01/17/1984US4426587 Power supply distribution system
01/17/1984CA1160782A1 Telephone handsets
01/17/1984CA1160780A1 Trunk interface circuit with current compensation
01/10/1984US4425512 Power supply system
01/04/1984EP0097354A2 Circuit arrangement for determining the busy condition of a subscriber line in telecommunication exchanges
01/03/1984CA1159975A1 Communication system signaling circuit
12/1983
12/28/1983EP0096965A1 Active impedance transformer assisted line feed circuit
12/28/1983EP0096756A2 Electronic subscriber junctor
12/27/1983US4423292 Detector circuit for communication lines
12/27/1983CA1159584A1 Telephone power supply arrangement
12/21/1983EP0096473A1 Active impedance line feed circuit
12/20/1983US4421953 Telephone tactile alert system
12/20/1983CA1159174A1 Telephone line circuit
12/13/1983US4420786 Polarity guard circuit
12/13/1983CA1158789A1 Filters comprising reactive components, and a method of determining impedances thereof
12/06/1983US4419542 Battery feed circuit
12/06/1983CA1158376A1 Arrangement for feeding a subscriber device
11/1983
11/29/1983CA1157978A1 Loop sensing circuit for use with a subscriber loop interface circuit
11/22/1983US4417099 Electro-optical isolator circuit for line powered modem
11/22/1983CA1157597A1 Current supplying circuit with shorted-to-ground fault detecting function
11/22/1983CA1157596A1 Ringing signal supply
11/22/1983CA1157595A1 Ringing signal supply
11/16/1983EP0094162A2 A method of producing voltage signals with a dc component and great dynamic range
11/15/1983US4415961 Telephone ringing signal generator
11/15/1983US4415775 Arrangement for exchanging signals between separated circuits
11/15/1983CA1157175A1 Power saving line circuit
11/10/1983WO1983003940A1 Circuit for a coin-operated telephone apparatus
11/08/1983US4414435 Interface circuit with flux cancelling transformer circuit
11/08/1983US4414434 Electronic subscriber line interface circuit having means to equalize current through the output differential amplifier
11/08/1983CA1156749A1 Signal control system
11/02/1983EP0092820A1 Circuit arrangement for the overvoltage protection of intersection circuits
11/02/1983EP0092807A2 A digital supervisory circuit for a telephone system
10/1983
10/25/1983CA1155986A2 Current weighting circuit
10/19/1983EP0091630A1 Device for engaging the line without lifting the hook of a telephone set comprising a microprocessor
10/19/1983EP0091614A2 Circuit arrangement for telecommunication exchanges, especially telephone exchanges, with circuits for emitting signals
10/18/1983US4410766 Power saving line circuit
10/13/1983WO1983003504A1 Supply circuit included in a dc-magnetized hybrid transformer
10/11/1983US4409439 Controllable telephone call annunciator
10/11/1983US4409438 Ringing control circuit in a telephone switching system
10/11/1983CA1155244A1 Apparatus for regulating current supplied to a telephone line
10/04/1983US4408153 Current supplementation circuit for power supply
09/1983
09/28/1983EP0089687A2 Method of and electronic device for detecting the lifting of the telephone handset in presence of ringing current
09/28/1983EP0089350A1 Electronic terminator circuit
09/27/1983USRE31398 Electronic audio signalling device for telephones
09/27/1983US4406929 Hook status detector for a subscriber loop interface circuit
09/27/1983US4406927 Electronic tone ringer
09/20/1983US4406004 Ring scheduling apparatus for a digital multiplexed telecommunication system
09/20/1983CA1154185A1 Subscriber line interface circuit
09/20/1983CA1154184A1 Circuits and methods for initializing the loop current of a telephone set
09/13/1983CA1153838A1 Telephone circuit for ringing rhythm generation and off hook detection
09/07/1983EP0087784A2 Subscriber line circuit comprising low-resistance shuntable feeding resistors and an indication circuit realising different indications
09/06/1983US4403115 Station identification circuit arrangement
08/1983
08/30/1983US4402039 Telephone line circuit
08/23/1983CA1152663A1 Apparatus for detecting the closure of a subscriber's line during ringing
08/23/1983CA1152579A1 Device for controlling a digital signal generator
08/17/1983EP0086183A2 Electronic external line repeater
08/17/1983EP0086182A2 Electronic impedance-matched line repeater
08/16/1983CA1152241A1 Telephone loop resistance detector
08/10/1983EP0085256A2 Digital time-division switch
08/09/1983US4398143 Remote supply circuit for analog two-wire connection
08/03/1983EP0084721A1 Solid state relay
08/02/1983US4396805 Ring trip detector for a subscriber line interface circuit
08/02/1983CA1151331A1 Amplifier for use in a line circuit
07/1983
07/12/1983US4393496 Method for feeding call progress tones into conference connections
07/06/1983EP0083281A1 Process and device for powering a subscriber terminal
06/1983
06/29/1983EP0082791A1 Signal transmission device over a line also assuring a D.C. current supply
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