JPS5449016A - Fault supervisory system - Google Patents

Fault supervisory system

Info

Publication number
JPS5449016A
JPS5449016A JP11584577A JP11584577A JPS5449016A JP S5449016 A JPS5449016 A JP S5449016A JP 11584577 A JP11584577 A JP 11584577A JP 11584577 A JP11584577 A JP 11584577A JP S5449016 A JPS5449016 A JP S5449016A
Authority
JP
Japan
Prior art keywords
return
signal
subscriber
line
fault
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
JP11584577A
Other languages
Japanese (ja)
Inventor
Tsunetoshi Mizusawa
Masaharu Shimada
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.)
NEC Corp
NTT Inc
Original Assignee
NEC Corp
Nippon Telegraph and Telephone Corp
Nippon Electric Co 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 NEC Corp, Nippon Telegraph and Telephone Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP11584577A priority Critical patent/JPS5449016A/en
Publication of JPS5449016A publication Critical patent/JPS5449016A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/46—Monitoring; Testing

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Dc Digital Transmission (AREA)
  • Monitoring And Testing Of Transmission In General (AREA)

Abstract

PURPOSE:To discriminate the fault of a subscriber's line easily through the AND operation between a return signal and a photo coupler detection signal which indicates whether or not an automatic return signal has flowed. CONSTITUTION:Terminating set 14 detects an automatic return operation signal from intra-office device 3 of the system which makes base band transmission through subscriber's lines 12 and 13, and device 14 makes the return connections of transmitting and receiving subscribers. In device 3, photo coupler 23 detects an automatic return operation signal, a return signal is generated and then sent to subscriber's line 12 return-connected from transmission part 5 of device 3 at device 14, the return signal received by return signal reception part 7 of device 3 and the signal detected by photo coupler 23 are AND-ed 23. Consequently, the fault of a subscriber's line can be discriminated easily.
JP11584577A 1977-09-26 1977-09-26 Fault supervisory system Pending JPS5449016A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11584577A JPS5449016A (en) 1977-09-26 1977-09-26 Fault supervisory system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11584577A JPS5449016A (en) 1977-09-26 1977-09-26 Fault supervisory system

Publications (1)

Publication Number Publication Date
JPS5449016A true JPS5449016A (en) 1979-04-18

Family

ID=14672548

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11584577A Pending JPS5449016A (en) 1977-09-26 1977-09-26 Fault supervisory system

Country Status (1)

Country Link
JP (1) JPS5449016A (en)

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