GB1499961A - Telephone exchanges with protective arrangements for the switching network - Google Patents
Telephone exchanges with protective arrangements for the switching networkInfo
- 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
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.
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)
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)
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)
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 |
-
1975
- 1975-01-16 DE DE2501651A patent/DE2501651C2/en not_active Expired
-
1976
- 1976-01-08 GB GB626/76A patent/GB1499961A/en not_active Expired
- 1976-01-12 NO NO760072A patent/NO143185C/en unknown
- 1976-01-13 SE SE7600255A patent/SE411089B/en unknown
- 1976-01-14 NL NL7600332A patent/NL7600332A/en not_active Application Discontinuation
- 1976-01-14 CH CH36676A patent/CH604456A5/xx not_active IP Right Cessation
- 1976-01-15 IT IT19269/76A patent/IT1054944B/en active
- 1976-01-15 ES ES444317A patent/ES444317A1/en not_active Expired
- 1976-01-15 DK DK15176*#A patent/DK15176A/en not_active Application Discontinuation
- 1976-01-16 AU AU10367/76A patent/AU501744B2/en not_active Expired
- 1976-01-16 FR FR7601109A patent/FR2298215A1/en active Granted
- 1976-01-16 BE BE2054764A patent/BE837625R/en not_active IP Right Cessation
Cited By (2)
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 |