JPS55104191A - Detection system of recall signal - Google Patents

Detection system of recall signal

Info

Publication number
JPS55104191A
JPS55104191A JP1038679A JP1038679A JPS55104191A JP S55104191 A JPS55104191 A JP S55104191A JP 1038679 A JP1038679 A JP 1038679A JP 1038679 A JP1038679 A JP 1038679A JP S55104191 A JPS55104191 A JP S55104191A
Authority
JP
Japan
Prior art keywords
state
caller
relay
trunk
called party
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
JP1038679A
Other languages
Japanese (ja)
Inventor
Seizo Shinkawa
Tsutomu Minoshima
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 JP1038679A priority Critical patent/JPS55104191A/en
Publication of JPS55104191A publication Critical patent/JPS55104191A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements

Landscapes

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

Abstract

PURPOSE:To hold the outgoing trunk receiving the control signal to busy state, by easily detecting called party restoring state caused after the caller advance call state with the relay trunk between stations and the state of caller recall from the called party. CONSTITUTION:The exchanger in which the restoration control system of relay line trunk between stations is called party control system and the ground state of the terminals A2, B2 of the incoming trunk of called station is taken as caller recall information at the detected time, is provided. Further, after the response of called party, the relay R operated when the relay E is restored is provided in parallel with the loop system response monitor circuit connected between the terminals A1 and B1 opposing to the incoming trunk of the called station of the outgoing trunk of calling station side, and this relay R is operated when current flows from the terminal B1 to A1. With the combination of the relays R, A and E for the operation and restoration state and collation with caller state called party ON-hook at caller ON-hook or the state of recall of caller can distinctedly be detected.
JP1038679A 1979-02-02 1979-02-02 Detection system of recall signal Pending JPS55104191A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1038679A JPS55104191A (en) 1979-02-02 1979-02-02 Detection system of recall signal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1038679A JPS55104191A (en) 1979-02-02 1979-02-02 Detection system of recall signal

Publications (1)

Publication Number Publication Date
JPS55104191A true JPS55104191A (en) 1980-08-09

Family

ID=11748670

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1038679A Pending JPS55104191A (en) 1979-02-02 1979-02-02 Detection system of recall signal

Country Status (1)

Country Link
JP (1) JPS55104191A (en)

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