by reversing the polarity of the current at the exchange

Industry

CPC
H04M19/023

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Parent Industries

HELECTRICITY H04Electric communication H04MTELEPHONIC COMMUNICATION H04M19/00Current supply arrangements for telephone systems

Current Industry

H04M19/023by reversing the polarity of the current at the exchange

Industries

Patents Grantslast 30 patents

Information Patent Grant
Method and device for checking the function for inverting the polar...
- Patent number 8,107,615
- Issue date Jan 31, 2012
- Nokia Siemens Networks GmbH & Co. KG
- Heike Diegel
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Receiver and signal transmission system
- Patent number 6,600,791
- Issue date Jul 29, 2003
- Matsushita Electric Industrial Co., Ltd.
- Hiroyuki Yamauchi
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Leadframe for plastic-encapsulated semiconductor device, semiconduc...
- Patent number 5,723,996
- Issue date Mar 3, 1998
- Siemens Aktiengesellschaft
- Bernhard Zojer
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Method of providing d.c. feed to a telephone line
- Patent number 5,511,118
- Issue date Apr 23, 1996
- Northern Telecom Limited
- Stanley A. Gores
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Polarity inverting circuit
- Patent number 5,191,507
- Issue date Mar 2, 1993
- NEC Corporation
- Koichi Saito
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Line interface circuit
- Patent number 5,014,305
- Issue date May 7, 1991
- Northern Telecom Limited
- Mihail S. Moisin
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Ringing signal generator
- Patent number 5,001,748
- Issue date Mar 19, 1991
- Siemens Transmission Systems, Inc.
- Robert V. Burns
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Isolated drive circuit
- Patent number 4,908,857
- Issue date Mar 13, 1990
- Siemens Transmission Systems, Inc.
- Robert V. Burns
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Electronic ringing signal generator
- Patent number 4,866,587
- Issue date Sep 12, 1989
- American Telephone and Telegraph Company AT&T Bell Laboratories
- James C. Wadlington
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Integrated ringing circuit and a ring trip circuit for the same
- Patent number 4,827,503
- Issue date May 2, 1989
- Fujitsu Limited
- Kenji Takato
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Ringing circuit
- Patent number 4,737,989
- Issue date Apr 12, 1988
- The General Electric Company, p.l.c.
- Michael A. C. Robson
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Line circuit for driving a ringer and a service indicating lamp in...
- Patent number 4,726,060
- Issue date Feb 16, 1988
- Fujitsu Limited
- Masaki Itoh
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Power amplifier
- Patent number 4,703,500
- Issue date Oct 27, 1987
- Northern Telecom Limited
- Brian J. Pollard
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Programmable ring signal generator
- Patent number 4,656,659
- Issue date Apr 7, 1987
- ITT Corporation
- Ramon C. W. Chea
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
High efficiency ringing generator
- Patent number 4,648,019
- Issue date Mar 3, 1987
- GTE Communication Systems Corporation
- Douglas C. Stahl
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Programmable ring generator
- Patent number 4,631,361
- Issue date Dec 23, 1986
- ITT Corporation
- Robert L. Miller
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Sine wave ring generator
- Patent number 4,611,097
- Issue date Sep 9, 1986
- Rockwell International
- Mark W. Grimes
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Driver circuit
- Patent number 4,535,303
- Issue date Aug 13, 1985
- U.S. Philips Corporation
- Franciscus A. C. M. Schoofs
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Ringing signal generator employing delta-modulation power amplifica...
- Patent number 4,500,844
- Issue date Feb 19, 1985
- AT&T Bell Laboratories
- Richard J. Lisco
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Telephone line interface
- Patent number 4,489,222
- Issue date Dec 18, 1984
- The Board of Trustees of the Leland Stanford, Junior University
- Bruce B. Lusignan
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Telephone ringing signal generator
- Patent number 4,436,960
- Issue date Mar 13, 1984
- Bell Telephone Laboratories, Incorporated
- William R. Harmon
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Telephone ringing signal generator
- Patent number 4,415,961
- Issue date Nov 15, 1983
- Bell Telephone Laboratories, Incorporated
- William R. Harmon
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Ring scheduling apparatus for a digital multiplexed telecommunicati...
- Patent number 4,406,004
- Issue date Sep 20, 1983
- Anaconda-Ericsson, Inc.
- Jay D. Hall
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Arrangement for applying a ringing voltage to a subscriber's line
- Patent number 4,370,526
- Issue date Jan 25, 1983
- U.S. Philips Corporation
- Franciscus A. C. M. Schoofs
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Communication system signaling circuit
- Patent number 4,354,062
- Issue date Oct 12, 1982
- Bell Telephone Laboratories, Incorporated
- Harry E. Mussman
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Programmable ring signal generator
- Patent number 4,349,703
- Issue date Sep 14, 1982
- International Telephone & Telegraph Corporation
- Ramon C. W. Chea
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Ringing signal supply
- Patent number 4,341,928
- Issue date Jul 27, 1982
- Northern Telecom Limited
- Mark V. Stanson
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Ringing signal supply
- Patent number 4,340,785
- Issue date Jul 20, 1982
- Northern Telecom Limited
- Makary M. Awadalla
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Subscriber's connecting network comprising a symmetrical power ampl...
- Patent number 4,321,430
- Issue date Mar 23, 1982
- Telecommunications Radioelectriques et Telephoniques T.R.T.
- Gilbert M. M. Ferrieu
- H04 - ELECTRIC COMMUNICATION TECHNIQUE
Information Patent Grant
Ringing generator
- Patent number 4,220,826
- Issue date Sep 2, 1980
- Mitel Corporation
- William B. Kiss
- H04 - ELECTRIC COMMUNICATION TECHNIQUE

Patents Applicationslast 30 patents

Information Patent Application
Method and Device For Checking the Function For Inverting the Polar...
- Publication number 20080253534
- Publication date Oct 16, 2008
- Nokia Siemens Networks GmbH & Co. KG
- Heike Diegel
- H04 - ELECTRIC COMMUNICATION TECHNIQUE

by reversing the polarity of the current at the exchange

Industry

Parent Industries

Current Industry

Patents Grantslast 30 patents

Method and device for checking the function for inverting the polar...

Receiver and signal transmission system

Leadframe for plastic-encapsulated semiconductor device, semiconduc...

Method of providing d.c. feed to a telephone line

Polarity inverting circuit

Line interface circuit

Ringing signal generator

Isolated drive circuit

Electronic ringing signal generator

Integrated ringing circuit and a ring trip circuit for the same

Ringing circuit

Line circuit for driving a ringer and a service indicating lamp in...

Power amplifier

Programmable ring signal generator

High efficiency ringing generator

Programmable ring generator

Sine wave ring generator

Driver circuit

Ringing signal generator employing delta-modulation power amplifica...

Telephone line interface

Telephone ringing signal generator

Telephone ringing signal generator

Ring scheduling apparatus for a digital multiplexed telecommunicati...

Arrangement for applying a ringing voltage to a subscriber's line

Communication system signaling circuit

Programmable ring signal generator

Ringing signal supply

Ringing signal supply

Subscriber's connecting network comprising a symmetrical power ampl...

Ringing generator

Patents Applicationslast 30 patents

Method and Device For Checking the Function For Inverting the Polar...