GB148444A - Improvements in multiplex telephony - Google Patents

Improvements in multiplex telephony

Info

Publication number
GB148444A
GB148444A GB20399/20A GB2039920A GB148444A GB 148444 A GB148444 A GB 148444A GB 20399/20 A GB20399/20 A GB 20399/20A GB 2039920 A GB2039920 A GB 2039920A GB 148444 A GB148444 A GB 148444A
Authority
GB
United Kingdom
Prior art keywords
transformers
transformer
modulated
frequency
oscillations
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
GB20399/20A
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.)
Telefunken AG
Original Assignee
Telefunken Gesellschaft fuer Drahtlose Telegraphie mbH
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 Telefunken Gesellschaft fuer Drahtlose Telegraphie mbH filed Critical Telefunken Gesellschaft fuer Drahtlose Telegraphie mbH
Publication of GB148444A publication Critical patent/GB148444A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J1/00—Frequency-division multiplex systems

Landscapes

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

Abstract

148,444. Ges. f³r Drahtlose Telegraphie. May 27, 1919, [Convention date]. Addition to 147,837. Electric oscillations in line wires, telephoning by; electric oscillations, producing.-Relates to systems in which high-frequency oscillations, modulated by speech currents, are superposed on ordinary telephone circuits. Speech currents from a sub-station 3 are connected by a transformer 4 to a long-distance line 1, 2, while substation 5 is connected by transformers 6, 10, 11 to high-frequency generating and receiving sets 12, 13. The windings 7, 8, 9 of the transformers may bo in series or in parallel, the resistance of winding 7 being low in the former case and high in the latter case so as to absorb little of the received energy. The high-frequency current is modulated by connecting the secondary of transformer 10 across a condenser in the grid circuit of the valve 12. A coupling 14 is arranged to pevent inter-action between the transmitting and receiving sets 12, 13.
GB20399/20A 1918-12-14 1920-07-10 Improvements in multiplex telephony Expired GB148444A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE147837X 1918-12-14
DE148444X 1929-07-25

Publications (1)

Publication Number Publication Date
GB148444A true GB148444A (en) 1921-10-10

Family

ID=25752264

Family Applications (2)

Application Number Title Priority Date Filing Date
GB19886/20A Expired GB147837A (en) 1918-12-14 1920-07-09 Improvements in multiplex telephony
GB20399/20A Expired GB148444A (en) 1918-12-14 1920-07-10 Improvements in multiplex telephony

Family Applications Before (1)

Application Number Title Priority Date Filing Date
GB19886/20A Expired GB147837A (en) 1918-12-14 1920-07-09 Improvements in multiplex telephony

Country Status (1)

Country Link
GB (2) GB147837A (en)

Also Published As

Publication number Publication date
GB147837A (en) 1921-10-10

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