GB634199A - Carrier current telephone systems - Google Patents

Carrier current telephone systems

Info

Publication number
GB634199A
GB634199A GB9412/47A GB941247A GB634199A GB 634199 A GB634199 A GB 634199A GB 9412/47 A GB9412/47 A GB 9412/47A GB 941247 A GB941247 A GB 941247A GB 634199 A GB634199 A GB 634199A
Authority
GB
United Kingdom
Prior art keywords
frequency
oscillator
pilot
carrier current
derived
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
GB9412/47A
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
Publication of GB634199A publication Critical patent/GB634199A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J1/00—Frequency-division multiplex systems
    • H04J1/02—Details
    • H04J1/06—Arrangements for supplying the carrier waves ; Arrangements for supplying synchronisation signals
    • H04J1/065—Synchronisation of carrier sources at the receiving station with the carrier source at the transmitting station

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Radio Relay Systems (AREA)

Abstract

634,199. Valve generating circuits. STANDARD TELEPHONES & CABLES, Ltd. April 9, 1947, No. 9412. Convention date, Feb. 15, 1946. [Class 40 (vi)] [Also in Group XXXIX] In a carrier current communication system in which all the carrier frequencies are derived from a basic frequency f0, the generator is stabilized by a frequency equal to the basic frequency derived from modulating the output f3=2mf0 from a crystal controlled pilot oscillator with the harmonic (2m-1)f0, where m is any integer. The basic frequency f0 from the oscillator 1A is fed into the harmonic generator 2A from which the carriers F1, F2, F3, the pilot frequency f1=mf0 for control of the distant end, and the frequency f2=(2m-1)f0 are selected. The output f3=2mf0 from the oscillator 9A is modulated in 8A to produce the difference frequency f0 for stabilizing 1A. At station B Of3 is obtained by frequency doubling the pilot frequency f1.
GB9412/47A 1946-02-15 1947-04-09 Carrier current telephone systems Expired GB634199A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR634199X 1946-02-15

Publications (1)

Publication Number Publication Date
GB634199A true GB634199A (en) 1950-03-15

Family

ID=8993410

Family Applications (1)

Application Number Title Priority Date Filing Date
GB9412/47A Expired GB634199A (en) 1946-02-15 1947-04-09 Carrier current telephone systems

Country Status (1)

Country Link
GB (1) GB634199A (en)

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