GB659629A - Improvements in or relating to telephone transmission systems - Google Patents

Improvements in or relating to telephone transmission systems

Info

Publication number
GB659629A
GB659629A GB502349A GB502349A GB659629A GB 659629 A GB659629 A GB 659629A GB 502349 A GB502349 A GB 502349A GB 502349 A GB502349 A GB 502349A GB 659629 A GB659629 A GB 659629A
Authority
GB
United Kingdom
Prior art keywords
filter
audio
line
lines
transmission
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
GB502349A
Inventor
Charles Francis Campbell
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.)
Automatic Telephone and Electric Co Ltd
Original Assignee
Automatic Telephone and Electric Co 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 Automatic Telephone and Electric Co Ltd filed Critical Automatic Telephone and Electric Co Ltd
Priority to GB502349A priority Critical patent/GB659629A/en
Publication of GB659629A publication Critical patent/GB659629A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/20—Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other

Landscapes

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

Abstract

659,629. Multiplex transmission. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd. Feb. 24, 1949, No. 5023. [Class 40 (iv)] [Also in Group XL (b)] A telephone transmission system includes two two-conductor lines L1 and L2 between two stations, one or both of these lines being used for carrier and physical audio-transmission, and the two lines being used jointly for an audio-phantom circuit. As shown, a physical audio-circuit extends from point AA at station S1 over coil R1, low-pass filters LPFP and LPFA, line L1, low-pass filters LPFB and LPFQ and coil R4 to point AB. A 12-channel carrier system extends through filter TDFA, -high pass filter HPFA, line L1, filter HPFB to filter RDFB. A reverse transmission system is also obtained from filters TDFB to RDFA. A threechannel carrier system extends from filter TDFP over line L1 to RDFQ with a reverse system from TDFQ to RDFP. An equal number of paths can be provided over L2. An additional path is introduced by audio-phantom working between points PA and PB as shown.
GB502349A 1949-02-24 1949-02-24 Improvements in or relating to telephone transmission systems Expired GB659629A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB502349A GB659629A (en) 1949-02-24 1949-02-24 Improvements in or relating to telephone transmission systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB502349A GB659629A (en) 1949-02-24 1949-02-24 Improvements in or relating to telephone transmission systems

Publications (1)

Publication Number Publication Date
GB659629A true GB659629A (en) 1951-10-24

Family

ID=9788285

Family Applications (1)

Application Number Title Priority Date Filing Date
GB502349A Expired GB659629A (en) 1949-02-24 1949-02-24 Improvements in or relating to telephone transmission systems

Country Status (1)

Country Link
GB (1) GB659629A (en)

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