JPS547211A - Information transmitting system - Google Patents

Information transmitting system

Info

Publication number
JPS547211A
JPS547211A JP7206777A JP7206777A JPS547211A JP S547211 A JPS547211 A JP S547211A JP 7206777 A JP7206777 A JP 7206777A JP 7206777 A JP7206777 A JP 7206777A JP S547211 A JPS547211 A JP S547211A
Authority
JP
Japan
Prior art keywords
information transmitting
transmitting system
inverting
polarity
secure
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.)
Pending
Application number
JP7206777A
Other languages
Japanese (ja)
Inventor
Tsuneo Furuya
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.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
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 Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP7206777A priority Critical patent/JPS547211A/en
Publication of JPS547211A publication Critical patent/JPS547211A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/38—Signalling arrangements; Manipulation of signalling currents using combinations of direct currents of different amplitudes or polarities over line conductors or combination of line conductors

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

PURPOSE:To secure an economical information transmission of the trunk call from the originating register by inverting the polarity between A and B lines against the line unit in the public telephone circuit.
JP7206777A 1977-06-20 1977-06-20 Information transmitting system Pending JPS547211A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7206777A JPS547211A (en) 1977-06-20 1977-06-20 Information transmitting system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7206777A JPS547211A (en) 1977-06-20 1977-06-20 Information transmitting system

Publications (1)

Publication Number Publication Date
JPS547211A true JPS547211A (en) 1979-01-19

Family

ID=13478671

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7206777A Pending JPS547211A (en) 1977-06-20 1977-06-20 Information transmitting system

Country Status (1)

Country Link
JP (1) JPS547211A (en)

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