GB298952A - Improvements in high frequency telephone systems - Google Patents

Improvements in high frequency telephone systems

Info

Publication number
GB298952A
GB298952A GB29947/28A GB2994728A GB298952A GB 298952 A GB298952 A GB 298952A GB 29947/28 A GB29947/28 A GB 29947/28A GB 2994728 A GB2994728 A GB 2994728A GB 298952 A GB298952 A GB 298952A
Authority
GB
United Kingdom
Prior art keywords
frequency
line
relay
tone
ringing
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
GB29947/28A
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 AG
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 AG, Telefunken Gesellschaft fuer Drahtlose Telegraphie mbH filed Critical Telefunken AG
Publication of GB298952A publication Critical patent/GB298952A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M7/00—Arrangements for interconnection between switching centres
    • H04M7/16—Arrangements for interconnection between switching centres in systems employing carrier frequencies

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)

Abstract

298,952. Telefunken Ges. f³r Drahtlose Telegraphie. Oct. 17, 1927, [Convention date]. Wired-wireless signalling ; calling systems.-In a system in which calls arriving in high-frequency form from a long-distance line L or from the ether are directed to a wanted low-frequency line La, Lb, one or other of two tone signals to indicate that the wanted line is being rung or is busy is sent back by high-frequency currents modulated by a generator F or G brought into action by the ringing relay R or busy relay B. The relays R, B are associated with the incoming conversion channel E. The outgoing conversion channel S is brought into action either by the ring- ing relay R or by the line relay A of the wanted line. Ringing tone may be dispensed with, the mere return of high-frequency current from the channel S serving as a signal that ringing is in process. The tone currents may be collected from the direct-current dynamo that feeds the high-frequency apparatus. A single tone, continuous or interrupted, may be employed. Specification 267,151 is refererd to.
GB29947/28A 1927-10-17 1928-10-17 Improvements in high frequency telephone systems Expired GB298952A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE298952X 1927-10-17

Publications (1)

Publication Number Publication Date
GB298952A true GB298952A (en) 1930-02-17

Family

ID=6091127

Family Applications (1)

Application Number Title Priority Date Filing Date
GB29947/28A Expired GB298952A (en) 1927-10-17 1928-10-17 Improvements in high frequency telephone systems

Country Status (1)

Country Link
GB (1) GB298952A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2564378A (en) * 1946-05-06 1951-08-14 Punch Engineering Pty Ltd Carrier system signaling circuits

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2564378A (en) * 1946-05-06 1951-08-14 Punch Engineering Pty Ltd Carrier system signaling circuits

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