JPS526007A - Detection system of the off-hook stgnal of a called subscriber - Google Patents

Detection system of the off-hook stgnal of a called subscriber

Info

Publication number
JPS526007A
JPS526007A JP8183775A JP8183775A JPS526007A JP S526007 A JPS526007 A JP S526007A JP 8183775 A JP8183775 A JP 8183775A JP 8183775 A JP8183775 A JP 8183775A JP S526007 A JPS526007 A JP S526007A
Authority
JP
Japan
Prior art keywords
detection system
called subscriber
hook
stgnal
shall
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
JP8183775A
Other languages
Japanese (ja)
Inventor
Kozo Kamata
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 JP8183775A priority Critical patent/JPS526007A/en
Publication of JPS526007A publication Critical patent/JPS526007A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/2272—Subscriber line supervision circuits, e.g. call detection circuits

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

PURPOSE:In a detection system of the off-hook signal of a called subscriber at a four-wire telephone office, the miniaturization and the simplification shall be planned by performing this detection without a relay circuit and the occurrence of the swiching-office noise shall be reduced by constituting the circuit parallel to the earth.
JP8183775A 1975-07-04 1975-07-04 Detection system of the off-hook stgnal of a called subscriber Pending JPS526007A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP8183775A JPS526007A (en) 1975-07-04 1975-07-04 Detection system of the off-hook stgnal of a called subscriber

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8183775A JPS526007A (en) 1975-07-04 1975-07-04 Detection system of the off-hook stgnal of a called subscriber

Publications (1)

Publication Number Publication Date
JPS526007A true JPS526007A (en) 1977-01-18

Family

ID=13757571

Family Applications (1)

Application Number Title Priority Date Filing Date
JP8183775A Pending JPS526007A (en) 1975-07-04 1975-07-04 Detection system of the off-hook stgnal of a called subscriber

Country Status (1)

Country Link
JP (1) JPS526007A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5016707U (en) * 1973-06-11 1975-02-22

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5016707U (en) * 1973-06-11 1975-02-22

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