GB1353367A - 4-wire telephone interconnection network - Google Patents

4-wire telephone interconnection network

Info

Publication number
GB1353367A
GB1353367A GB1353367DA GB1353367A GB 1353367 A GB1353367 A GB 1353367A GB 1353367D A GB1353367D A GB 1353367DA GB 1353367 A GB1353367 A GB 1353367A
Authority
GB
United Kingdom
Prior art keywords
line
terminals
input
sets
conjugate
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
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 GB1353367A publication Critical patent/GB1353367A/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
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/48—Networks for connecting several sources or loads, working on the same frequency or frequency band, to a common load or source

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Telephonic Communication Services (AREA)

Abstract

1353367 Hybrid circuits; conference circuits STANDARD TELEPHONES & CABLES Ltd 2 Sept 1971 41097/71 Headings H4R and H4K Circuit network which has pairs of terminals which are conjugate, one pair to another, comprises a regular polygon of 2n sides, where n is greater than 3, each side of the polygon comprising an impedance arm and each diagonal of the polygon representing a pair of terminals of the network for connection to a balanced apparatus or a balanced line, and the impedance of the arms being such that at least two of the pairs of terminals are conjugate. As described with respect to Fig. 7 a preferred embodiment is for interconnecting two telephone sets 1, and 2, to a four wire line 1, 2, to provide a conference circuit. The twelve resistors a and c, are connected in series in a closed loop with each diagonal of the loop connected to a respective input or output of a set or a line, and the inputs and outputs of each set, and of the four wire line, connected to diagonals which are at right angles to each other, so that the input of each set, or the line, is decoupled, or conjugate to, its respective output. The values of the impedance arms are such that loss between the send terminals of one set and the receive terminal of the other set, and the input to the amplifier of the outgoing line, is approximately equal the difference in normal level at the outgoing and incoming terminals of the line, while the amplifier gains are such as to cancel that loss, so that the input and output levels of the sets are the same as if each was alone connected to the lines. In order to provide a greater number of participants in a conference each of the sets, 1 and 2, can be replaced by a similar network connected to two further sets, or further networks in a branching tree fashion.
GB1353367D 1971-09-02 1971-09-02 4-wire telephone interconnection network Expired GB1353367A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB4109771 1971-09-02

Publications (1)

Publication Number Publication Date
GB1353367A true GB1353367A (en) 1974-05-15

Family

ID=10418108

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1353367D Expired GB1353367A (en) 1971-09-02 1971-09-02 4-wire telephone interconnection network

Country Status (2)

Country Link
DE (1) DE2243060C2 (en)
GB (1) GB1353367A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4140875A (en) * 1978-03-27 1979-02-20 Bejed, Inc. Four-wire, eight-leg bridge
US4286114A (en) * 1980-02-12 1981-08-25 Bejed, Inc. Two-wire resistance bridges for private line circuits

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1078181B (en) * 1958-07-29 1960-03-24 Siemens Ag Loss-free adaptation network for transmission equipment in electrical communications engineering, preferably conference calls
DE1150124B (en) * 1962-01-05 1963-06-12 Telefunken Patent Circuit arrangement for the supply of a common load by three high-frequency generators
DE1230474B (en) * 1964-11-05 1966-12-15 Telefunken Patent Bridge arrangement for the mutual decoupling of two high-frequency generators of the same frequency with a common output resistance
USB351737I5 (en) * 1966-05-02

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4140875A (en) * 1978-03-27 1979-02-20 Bejed, Inc. Four-wire, eight-leg bridge
US4286114A (en) * 1980-02-12 1981-08-25 Bejed, Inc. Two-wire resistance bridges for private line circuits

Also Published As

Publication number Publication date
DE2243060C2 (en) 1983-01-05
DE2243060A1 (en) 1973-03-15

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Legal Events

Date Code Title Description
PS Patent sealed
746 Register noted 'licences of right' (sect. 46/1977)
PCNP Patent ceased through non-payment of renewal fee