GB1499961A - Telephone exchanges with protective arrangements for the switching network - Google Patents

Telephone exchanges with protective arrangements for the switching network

Info

Publication number
GB1499961A
GB1499961A GB626/76A GB62676A GB1499961A GB 1499961 A GB1499961 A GB 1499961A GB 626/76 A GB626/76 A GB 626/76A GB 62676 A GB62676 A GB 62676A GB 1499961 A GB1499961 A GB 1499961A
Authority
GB
United Kingdom
Prior art keywords
impedances
switches
switching network
jan
reduction device
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB626/76A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by International Standard Electric Corp filed Critical International Standard Electric Corp
Publication of GB1499961A publication Critical patent/GB1499961A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/42—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker
    • H04Q3/52—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker using static devices in switching stages, e.g. electronic switching arrangements
    • H04Q3/521—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker using static devices in switching stages, e.g. electronic switching arrangements using semiconductors in the switching stages

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Emergency Protection Circuit Devices (AREA)
  • Gyroscopes (AREA)
  • Control Of Eletrric Generators (AREA)
  • Optical Recording Or Reproduction (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

1499961 Automatic exchange systems INTERNATIONAL STANDARD ELECTRIC CORP 8 Jan 1976 [16 Jan 1975] 00626/76 Heading H4K A path through an electronic switching network EKF, constituted by switches having resistances Ra1-Ran, Rb1-Rbn is coupled to a line transformer UET and a junctor transformer UEV via an arrangement of Zener diodes Z1-Z6 and impedances R1, R2 substantially as shown, and a damping reduction device NIC is provided with a negative impedance such that the total series impedance across the switches, the impedances R1, R2 and the clamping reduction device is zero. The impedances R1, R2 may be resistors or inductors having air-core coils. The purpose of the Zener diodes is to protect the switches against over voltages.
GB626/76A 1975-01-16 1976-01-08 Telephone exchanges with protective arrangements for the switching network Expired GB1499961A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2501651A DE2501651C2 (en) 1975-01-16 1975-01-16 Circuit arrangement for overvoltage protection of electronic switching matrices

Publications (1)

Publication Number Publication Date
GB1499961A true GB1499961A (en) 1978-02-01

Family

ID=5936610

Family Applications (1)

Application Number Title Priority Date Filing Date
GB626/76A Expired GB1499961A (en) 1975-01-16 1976-01-08 Telephone exchanges with protective arrangements for the switching network

Country Status (12)

Country Link
AU (1) AU501744B2 (en)
BE (1) BE837625R (en)
CH (1) CH604456A5 (en)
DE (1) DE2501651C2 (en)
DK (1) DK15176A (en)
ES (1) ES444317A1 (en)
FR (1) FR2298215A1 (en)
GB (1) GB1499961A (en)
IT (1) IT1054944B (en)
NL (1) NL7600332A (en)
NO (1) NO143185C (en)
SE (1) SE411089B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0781019A2 (en) * 1995-12-21 1997-06-25 Siemens Aktiengesellschaft Circuit for the protection of a subscriber line circuit of a telecommunication system

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2419625A1 (en) * 1978-03-07 1979-10-05 Labo Cent Telecommunicat Overvoltage protector for telephone subscriber equipment - has each line grounded by triac controlled by back-to-back Zener diode
DE3334952A1 (en) * 1983-09-27 1985-04-18 Siemens AG, 1000 Berlin und 8000 München CIRCUIT ARRANGEMENT FOR PROTECTING AN ELECTRONIC CIRCUIT CONNECTED TO THE FOURWIRE SIDE OF A TRANSMISSION FORK

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL268951A (en) * 1960-09-07
US3452157A (en) * 1966-02-01 1969-06-24 Itt Current controlled,self-seeking telephone switching system
US3558830A (en) * 1969-04-09 1971-01-26 Communication Technology Inc Overvoltage transmission line protector
DE2419288C2 (en) * 1974-04-22 1982-04-29 Standard Elektrik Lorenz Ag, 7000 Stuttgart Circuit arrangement for de-attenuation and equalization of electronic switches, in particular of electronic coupling elements of a telephone exchange

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0781019A2 (en) * 1995-12-21 1997-06-25 Siemens Aktiengesellschaft Circuit for the protection of a subscriber line circuit of a telecommunication system
EP0781019A3 (en) * 1995-12-21 2003-08-27 Siemens Aktiengesellschaft Circuit for the protection of a subscriber line circuit of a telecommunication system

Also Published As

Publication number Publication date
AU1036776A (en) 1977-07-28
SE7600255L (en) 1976-07-19
AU501744B2 (en) 1979-06-28
DK15176A (en) 1976-07-17
NL7600332A (en) 1976-07-20
NO760072L (en) 1976-07-19
BE837625R (en) 1976-07-16
NO143185C (en) 1980-12-29
ES444317A1 (en) 1977-05-01
DE2501651A1 (en) 1976-07-22
NO143185B (en) 1980-09-15
FR2298215B1 (en) 1982-09-24
IT1054944B (en) 1981-11-30
SE411089B (en) 1979-11-26
CH604456A5 (en) 1978-09-15
DE2501651C2 (en) 1982-11-04
FR2298215A1 (en) 1976-08-13

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Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PCNP Patent ceased through non-payment of renewal fee