JPS56107172A - Terrestrial magnetic disturbance detection - Google Patents

Terrestrial magnetic disturbance detection

Info

Publication number
JPS56107172A
JPS56107172A JP1038680A JP1038680A JPS56107172A JP S56107172 A JPS56107172 A JP S56107172A JP 1038680 A JP1038680 A JP 1038680A JP 1038680 A JP1038680 A JP 1038680A JP S56107172 A JPS56107172 A JP S56107172A
Authority
JP
Japan
Prior art keywords
magnetic disturbance
terrestrial magnetic
signal sound
disturbance detection
balance line
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
JP1038680A
Other languages
Japanese (ja)
Inventor
Yasuo Miyazaki
Kunio Yamamoto
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP1038680A priority Critical patent/JPS56107172A/en
Publication of JPS56107172A publication Critical patent/JPS56107172A/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)
  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)

Abstract

PURPOSE:To miniaturize and reduce the weight of a signal sound distribution/ supply device by connecting two pieces of diode to a terrestrial magnetic disturbance detection means for a balance line for signal sound transmission at a telephone exchange. CONSTITUTION:A signal sound distribution supply device TD branches off and extends a balance line from a signal sound generator TG to various trunk devices TSK and distributes/supplies signal sounds. A terrestrial magnetic disturbance detection relay AL is connected at a connection point of diodes D1 and D2 linked between balance lines. If a terrestrial magnetic disturbance occurred on the balance line, the relay AL works through the intermediary of D1 or D2, announcing the occurrence of a terrestrial magnetic disturbance E.
JP1038680A 1980-01-31 1980-01-31 Terrestrial magnetic disturbance detection Pending JPS56107172A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1038680A JPS56107172A (en) 1980-01-31 1980-01-31 Terrestrial magnetic disturbance detection

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1038680A JPS56107172A (en) 1980-01-31 1980-01-31 Terrestrial magnetic disturbance detection

Publications (1)

Publication Number Publication Date
JPS56107172A true JPS56107172A (en) 1981-08-25

Family

ID=11748672

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1038680A Pending JPS56107172A (en) 1980-01-31 1980-01-31 Terrestrial magnetic disturbance detection

Country Status (1)

Country Link
JP (1) JPS56107172A (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5491112A (en) * 1977-12-28 1979-07-19 Fujitsu Ltd External abnormal voltage detection system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5491112A (en) * 1977-12-28 1979-07-19 Fujitsu Ltd External abnormal voltage detection system

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