GB1257878A - - Google Patents

Info

Publication number
GB1257878A
GB1257878A GB1257878DA GB1257878A GB 1257878 A GB1257878 A GB 1257878A GB 1257878D A GB1257878D A GB 1257878DA GB 1257878 A GB1257878 A GB 1257878A
Authority
GB
United Kingdom
Prior art keywords
diagonal
resistors
transmitter
receiver
network
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
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 filed Critical
Publication of GB1257878A publication Critical patent/GB1257878A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
    • H04B1/40—Circuits
    • H04B1/54—Circuits using the same frequency for two directions of communication
    • H04B1/58—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa
    • H04B1/583—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa using a bridge network

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

1,257,878. Anti sidetone circuits. STANDARD TELEPHONES & CABLES Ltd. 10 April, 1970, No. 17212/70. Heading H4R. Two wire to four wire converter comprises a network of six resistors a...f connected in series in a ring with the line L connected across one diagonal FC, the transmitter across a second diagonal AD and the receiver across the third diagonal BE. Preferably the line, transmitter, and receiver, present balanced impedances and the diagonally opposed resistors are of equal impedance. The specification derives relationships between the values of the resistors and the impedances to which the network is connected to provide perfect anti side tone balance, such as is required in a loudspeaking telephone set, a given amount of side tone, as is required for a normal handset, and for various matching conditions, e.g. high or low impedance amplifier inputs or outputs.
GB1257878D 1970-04-10 1970-04-10 Expired GB1257878A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1721270 1970-04-10

Publications (1)

Publication Number Publication Date
GB1257878A true GB1257878A (en) 1971-12-22

Family

ID=10091190

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1257878D Expired GB1257878A (en) 1970-04-10 1970-04-10

Country Status (3)

Country Link
DE (1) DE2117292C3 (en)
FR (1) FR2089300A5 (en)
GB (1) GB1257878A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3987253A (en) * 1974-03-21 1976-10-19 Societa Italiana Telecomunicazioni Spa Hybrid coupling for telecommunication system
EP0246546A1 (en) * 1986-05-23 1987-11-25 Siemens Aktiengesellschaft Österreich Telephone subscriber circuit
FR2677196A1 (en) * 1991-05-31 1992-12-04 Sgs Thomson Microelectronics Passive two wire/four wire differential converter

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3987253A (en) * 1974-03-21 1976-10-19 Societa Italiana Telecomunicazioni Spa Hybrid coupling for telecommunication system
EP0246546A1 (en) * 1986-05-23 1987-11-25 Siemens Aktiengesellschaft Österreich Telephone subscriber circuit
US4914693A (en) * 1986-05-23 1990-04-03 Siemens Aktiengesellschaft Telephone subscriber circuit
FR2677196A1 (en) * 1991-05-31 1992-12-04 Sgs Thomson Microelectronics Passive two wire/four wire differential converter

Also Published As

Publication number Publication date
FR2089300A5 (en) 1972-01-07
DE2117292B2 (en) 1978-02-16
DE2117292A1 (en) 1971-10-28
DE2117292C3 (en) 1978-09-28

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Legal Events

Date Code Title Description
PS Patent sealed
435 Patent endorsed 'licences of right' on the date specified (sect. 35/1949)
PCNP Patent ceased through non-payment of renewal fee