GB896554A - Improvements in or relating to electrical signalling systems - Google Patents

Improvements in or relating to electrical signalling systems

Info

Publication number
GB896554A
GB896554A GB825959A GB825959A GB896554A GB 896554 A GB896554 A GB 896554A GB 825959 A GB825959 A GB 825959A GB 825959 A GB825959 A GB 825959A GB 896554 A GB896554 A GB 896554A
Authority
GB
United Kingdom
Prior art keywords
terminals
resistors
repeater
resistor
impedance
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
GB825959A
Inventor
Brian Stanley Helliwell
John Albert Barrett
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.)
British Telecommunications PLC
British Telecommunications Research Ltd
Original Assignee
British Telecommunications PLC
British Telecommunications Research Ltd
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 British Telecommunications PLC, British Telecommunications Research Ltd filed Critical British Telecommunications PLC
Priority to GB825959A priority Critical patent/GB896554A/en
Publication of GB896554A publication Critical patent/GB896554A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/26—Arrangements for supervision, monitoring or testing with means for applying test signals or for measuring
    • H04M3/28—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor
    • H04M3/32—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor for lines between exchanges
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/40—Applications of speech amplifiers

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

896,554. Unattended repeaters. BRITISH TELECOMMUNICATIONS RESEARCH Ltd. March 8, 1960 [March 10, 1959], No. 8259/59. Class 40 (4). A repeater station, such as a buried transistorized repeater on a cable, is provided with a test point T in a readily accessible position and having a low impedance between its two terminals so that poor insulation between the terminals does not appreciably prejudice operation of the station. The output of the repeater amplifier is connected to the primary of a transformer TR having the centre of its secondary connected to earth through an impedance Z which compensates for the impedance of the primary circuit. Resistor RA is considerably greater than resistor RB, and their combined value is slightly greater than the resistance RO of the line L1, L2. One of the test terminals T is connected to earth and the other is connected through a further resistor RC to the junction of resistors RA and RB. If a pilot signal is used for gain regulation, resistors RD and RE are added, forming with resistors RA and RB an attenuator. The output from terminals T1 and T2 is supplied to the pilot filter and thence through an amplifier to the gain regulator. Specifications 840,666 and 864,442 are referred to.
GB825959A 1959-03-10 1959-03-10 Improvements in or relating to electrical signalling systems Expired GB896554A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB825959A GB896554A (en) 1959-03-10 1959-03-10 Improvements in or relating to electrical signalling systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB825959A GB896554A (en) 1959-03-10 1959-03-10 Improvements in or relating to electrical signalling systems

Publications (1)

Publication Number Publication Date
GB896554A true GB896554A (en) 1962-05-16

Family

ID=9849074

Family Applications (1)

Application Number Title Priority Date Filing Date
GB825959A Expired GB896554A (en) 1959-03-10 1959-03-10 Improvements in or relating to electrical signalling systems

Country Status (1)

Country Link
GB (1) GB896554A (en)

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