JPS5792963A - Network control device - Google Patents

Network control device

Info

Publication number
JPS5792963A
JPS5792963A JP16786080A JP16786080A JPS5792963A JP S5792963 A JPS5792963 A JP S5792963A JP 16786080 A JP16786080 A JP 16786080A JP 16786080 A JP16786080 A JP 16786080A JP S5792963 A JPS5792963 A JP S5792963A
Authority
JP
Japan
Prior art keywords
photocoupler
power source
telephone set
relay
hook
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
JP16786080A
Other languages
Japanese (ja)
Inventor
Toshio Watanabe
Iwao Shimizu
Makoto Suzuki
Toshihiko Nishimura
Shigeru Okamura
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.)
JAPANESE NATIONAL RAILWAYS<JNR>
Japan National Railways
Mitsubishi Electric Corp
Nippon Kokuyu Tetsudo
Original Assignee
JAPANESE NATIONAL RAILWAYS<JNR>
Japan National Railways
Mitsubishi Electric Corp
Nippon Kokuyu Tetsudo
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 JAPANESE NATIONAL RAILWAYS<JNR>, Japan National Railways, Mitsubishi Electric Corp, Nippon Kokuyu Tetsudo filed Critical JAPANESE NATIONAL RAILWAYS<JNR>
Priority to JP16786080A priority Critical patent/JPS5792963A/en
Publication of JPS5792963A publication Critical patent/JPS5792963A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M11/00—Telephonic communication systems specially adapted for combination with other electrical systems
    • H04M11/06—Simultaneous speech and data transmission, e.g. telegraphic transmission over the same conductors

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)

Abstract

PURPOSE:To discriminate off-hook by a DC power source and discriminate on- hook by detecting the break of the power source of a line by a current detecting circuit, by providing the DC power source and the current detecting circuit in the device. CONSTITUTION:Under the state of no call, a relay A is operated, and the voltage of a DC power source 16 is applied to a telephone set 8; and therefore, when the telephone set 8 is hooked off, a DC loop is formed. Then, a photocoupler 18 becomes conductive, and an on-hook signal line 21 is set to L, and the relay A is released, and the telephone set 8 is connected to telephone lines L1 and L2 through the release side of a contact 14, and a loop through the power supply from telephone lines is formed, and the photocoupler 18 holds conduction. When the calling subscriber is connected to the called subscriber by dialing and the called subscriber answers, the voltage polarity of lines is inverted, and only a photocoupler 19 becomes conductive, and a signal line 21 holds the state. When the telephone set is hooked on at the completion of the call, the photocoupler 19 becomes non-conductive, and the relay A is released.
JP16786080A 1980-11-28 1980-11-28 Network control device Pending JPS5792963A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP16786080A JPS5792963A (en) 1980-11-28 1980-11-28 Network control device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP16786080A JPS5792963A (en) 1980-11-28 1980-11-28 Network control device

Publications (1)

Publication Number Publication Date
JPS5792963A true JPS5792963A (en) 1982-06-09

Family

ID=15857423

Family Applications (1)

Application Number Title Priority Date Filing Date
JP16786080A Pending JPS5792963A (en) 1980-11-28 1980-11-28 Network control device

Country Status (1)

Country Link
JP (1) JPS5792963A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61142850A (en) * 1984-12-17 1986-06-30 Oki Electric Ind Co Ltd Monitor system for terminal state

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5748859A (en) * 1980-09-08 1982-03-20 Toshiba Corp Network controller

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5748859A (en) * 1980-09-08 1982-03-20 Toshiba Corp Network controller

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61142850A (en) * 1984-12-17 1986-06-30 Oki Electric Ind Co Ltd Monitor system for terminal state

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