JPS5439510A - Detection circuit for outgoing call - Google Patents

Detection circuit for outgoing call

Info

Publication number
JPS5439510A
JPS5439510A JP10581877A JP10581877A JPS5439510A JP S5439510 A JPS5439510 A JP S5439510A JP 10581877 A JP10581877 A JP 10581877A JP 10581877 A JP10581877 A JP 10581877A JP S5439510 A JPS5439510 A JP S5439510A
Authority
JP
Japan
Prior art keywords
detection circuit
outgoing call
circuit
photocouplers
reliability
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
JP10581877A
Other languages
Japanese (ja)
Inventor
Tetsuo Takeshita
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 JP10581877A priority Critical patent/JPS5439510A/en
Publication of JPS5439510A publication Critical patent/JPS5439510A/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 perform current detection, to reject noise, and to increase the reliability of circuit, by connecting two photocouplers in loop, in the circuit monitoring the condition of the subscriber lines of a telephone exchanger.
JP10581877A 1977-09-05 1977-09-05 Detection circuit for outgoing call Pending JPS5439510A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10581877A JPS5439510A (en) 1977-09-05 1977-09-05 Detection circuit for outgoing call

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10581877A JPS5439510A (en) 1977-09-05 1977-09-05 Detection circuit for outgoing call

Publications (1)

Publication Number Publication Date
JPS5439510A true JPS5439510A (en) 1979-03-27

Family

ID=14417652

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10581877A Pending JPS5439510A (en) 1977-09-05 1977-09-05 Detection circuit for outgoing call

Country Status (1)

Country Link
JP (1) JPS5439510A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56156087A (en) * 1980-05-06 1981-12-02 Nec Corp Loop detecting circuit
JPH0274633A (en) * 1988-09-05 1990-03-14 Hiroshi Yamaguchi Bearing apparatus of rotary ring for spinning
JPH02229227A (en) * 1988-11-08 1990-09-12 Hiroshi Yamaguchi Rotary ring for spinning and device for controlling same ring
JPH0359787U (en) * 1989-10-16 1991-06-12

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS56156087A (en) * 1980-05-06 1981-12-02 Nec Corp Loop detecting circuit
JPH0274633A (en) * 1988-09-05 1990-03-14 Hiroshi Yamaguchi Bearing apparatus of rotary ring for spinning
JPH02229227A (en) * 1988-11-08 1990-09-12 Hiroshi Yamaguchi Rotary ring for spinning and device for controlling same ring
JPH0359787U (en) * 1989-10-16 1991-06-12

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