GB1530989A - Telephone exchange with attenuation equalisation means - Google Patents

Telephone exchange with attenuation equalisation means

Info

Publication number
GB1530989A
GB1530989A GB4013877A GB4013877A GB1530989A GB 1530989 A GB1530989 A GB 1530989A GB 4013877 A GB4013877 A GB 4013877A GB 4013877 A GB4013877 A GB 4013877A GB 1530989 A GB1530989 A GB 1530989A
Authority
GB
United Kingdom
Prior art keywords
circuit
amplifier
resistor
attenuation
telephone exchange
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
GB4013877A
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 GB1530989A publication Critical patent/GB1530989A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/04—Control of transmission; Equalising
    • H04B3/06—Control of transmission; Equalising by the transmitted signal
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/58—Arrangements providing connection between main exchange and sub-exchange or satellite
    • H04Q3/62—Arrangements providing connection between main exchange and sub-exchange or satellite for connecting to private branch exchanges

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • Astronomy & Astrophysics (AREA)
  • General Physics & Mathematics (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)
  • Use Of Switch Circuits For Exchanges And Methods Of Control Of Multiplex Exchanges (AREA)

Abstract

1530989 Attenuation equalizing arrangements INTERNATIONAL STANDARD ELECTRIC CORP 27 Sept 1977 [1 Oct 1976] 40138/77 Heading H4K In a telephone exchange, e.g. a PBX NST, having a variable-gain amplifier V for equalizing losses in the crosspoint array KF, a switchable shunt resistor RQ, S is connectible across the amplifier and the signal level during calls is determined by the fact that for short exchange lines AL, the resistor is connected in circuit, for normal exchange lines the amplifier is in circuit and the resistor is out of circuit, while for long exchange lines the resistor is out of circuit and the gain of the amplifier is increased.
GB4013877A 1976-10-01 1977-09-27 Telephone exchange with attenuation equalisation means Expired GB1530989A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19762644403 DE2644403C3 (en) 1976-10-01 1976-10-01 Circuit arrangement for attenuation compensation in a private branch exchange

Publications (1)

Publication Number Publication Date
GB1530989A true GB1530989A (en) 1978-11-01

Family

ID=5989454

Family Applications (1)

Application Number Title Priority Date Filing Date
GB4013877A Expired GB1530989A (en) 1976-10-01 1977-09-27 Telephone exchange with attenuation equalisation means

Country Status (4)

Country Link
BE (1) BE859107R (en)
DE (1) DE2644403C3 (en)
FR (1) FR2366749A1 (en)
GB (1) GB1530989A (en)

Also Published As

Publication number Publication date
DE2644403B2 (en) 1980-05-22
DE2644403A1 (en) 1978-04-06
FR2366749A1 (en) 1978-04-28
DE2644403C3 (en) 1985-01-31
BE859107R (en) 1978-03-28
FR2366749B1 (en) 1984-05-25

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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