GB1525057A - Regulating pabx/public exchange line loss - Google Patents

Regulating pabx/public exchange line loss

Info

Publication number
GB1525057A
GB1525057A GB4231476A GB4231476A GB1525057A GB 1525057 A GB1525057 A GB 1525057A GB 4231476 A GB4231476 A GB 4231476A GB 4231476 A GB4231476 A GB 4231476A GB 1525057 A GB1525057 A GB 1525057A
Authority
GB
United Kingdom
Prior art keywords
control
amplifiers
pabx
regulating
circuits
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
GB4231476A
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB4231476A priority Critical patent/GB1525057A/en
Priority to AU29552/77A priority patent/AU2955277A/en
Priority to CH1244577A priority patent/CH624521A5/en
Priority to BE2056335A priority patent/BE859616R/en
Publication of GB1525057A publication Critical patent/GB1525057A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/738—Interface circuits for coupling substations to external telephone lines
    • H04M1/76—Compensating for differences in line impedance

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Details Of Television Systems (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)

Abstract

To control the line attenuation between a PABX system and the exchange, the arrangement contains, inter alia, control amplifiers (14, 15) whose amplification level can be controlled by circuits (18, 19) which in each case act on a resistance network in the return path of the amplifiers. The connection between the hybrid circuit (16) of the extension and the exchange has a coupling device to couple a Hall effect device (17) to which a level detector device is connected which supplies coded output signals which categorise the line currents, i.e. divide them into value ranges. The aforementioned output signals act via the circuits (18, 19) on the amplification level of the control amplifiers (14, 15), thus achieving the aforementioned control effect. <IMAGE>
GB4231476A 1976-10-12 1976-10-12 Regulating pabx/public exchange line loss Expired GB1525057A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
GB4231476A GB1525057A (en) 1976-10-12 1976-10-12 Regulating pabx/public exchange line loss
AU29552/77A AU2955277A (en) 1976-10-12 1977-10-11 Line-loss regulator
CH1244577A CH624521A5 (en) 1976-10-12 1977-10-12 Arrangement for controlling the line attenuation of a connection line between a dial-up PABX system and a public telephone exchange
BE2056335A BE859616R (en) 1976-10-12 1977-10-12 AUTOMATIC NUMERIC PRIVATE CENTERS

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB4231476A GB1525057A (en) 1976-10-12 1976-10-12 Regulating pabx/public exchange line loss

Publications (1)

Publication Number Publication Date
GB1525057A true GB1525057A (en) 1978-09-20

Family

ID=10423889

Family Applications (1)

Application Number Title Priority Date Filing Date
GB4231476A Expired GB1525057A (en) 1976-10-12 1976-10-12 Regulating pabx/public exchange line loss

Country Status (4)

Country Link
AU (1) AU2955277A (en)
BE (1) BE859616R (en)
CH (1) CH624521A5 (en)
GB (1) GB1525057A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2478412A1 (en) * 1980-03-14 1981-09-18 Radiotechnique Compelec Automatic impedance appts. for telephone network - momentarily samples impedance magnitude and stores that data to provide stable information to adaptation system
EP0063748A1 (en) * 1981-04-24 1982-11-03 Licentia Patent-Verwaltungs-GmbH Circuit arrangement for the generation of control magnitudes from the loop current
FR2538648A1 (en) * 1982-12-28 1984-06-29 Thomson Csf MICROPHONE SIGNAL SUPPRESSION CIRCUIT FOR TELEPHONE SET
FR2540317A1 (en) * 1983-02-01 1984-08-03 Gesi Telephony terminal transmission circuit

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2478412A1 (en) * 1980-03-14 1981-09-18 Radiotechnique Compelec Automatic impedance appts. for telephone network - momentarily samples impedance magnitude and stores that data to provide stable information to adaptation system
EP0063748A1 (en) * 1981-04-24 1982-11-03 Licentia Patent-Verwaltungs-GmbH Circuit arrangement for the generation of control magnitudes from the loop current
FR2538648A1 (en) * 1982-12-28 1984-06-29 Thomson Csf MICROPHONE SIGNAL SUPPRESSION CIRCUIT FOR TELEPHONE SET
EP0114558A1 (en) * 1982-12-28 1984-08-01 Thomson-Csf Circuit for the suppression of a microphone signal in a telephone apparatus
FR2540317A1 (en) * 1983-02-01 1984-08-03 Gesi Telephony terminal transmission circuit

Also Published As

Publication number Publication date
BE859616R (en) 1978-04-12
AU2955277A (en) 1979-04-26
CH624521A5 (en) 1981-07-31

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Legal Events

Date Code Title Description
PS Patent sealed
746 Register noted 'licences of right' (sect. 46/1977)
PCNP Patent ceased through non-payment of renewal fee