JPS6416053A - Terminal equipment removal alarm system for telephone exchange - Google Patents

Terminal equipment removal alarm system for telephone exchange

Info

Publication number
JPS6416053A
JPS6416053A JP17088787A JP17088787A JPS6416053A JP S6416053 A JPS6416053 A JP S6416053A JP 17088787 A JP17088787 A JP 17088787A JP 17088787 A JP17088787 A JP 17088787A JP S6416053 A JPS6416053 A JP S6416053A
Authority
JP
Japan
Prior art keywords
signal
line
telephone set
detector
high frequency
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
JP17088787A
Other languages
Japanese (ja)
Inventor
Katsumi Morimoto
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.)
Meisei Electric Co Ltd
Original Assignee
Meisei 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 Meisei Electric Co Ltd filed Critical Meisei Electric Co Ltd
Priority to JP17088787A priority Critical patent/JPS6416053A/en
Publication of JPS6416053A publication Critical patent/JPS6416053A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To recognize instantly the removal of a terminal set by applying a high frequency signal at the outside of an audible frequency to one line of terminal connection lines and monitoring a high frequency signal through the other line of the terminal connection lines. CONSTITUTION:When a telephone set A is not busy, the high frequency signal sent rom a signal oscillator 11 of a monitor 13 is detected by a signal detector 12 via a line L1 of an extension line D, the said AC signal path in the telephone set A and a line L2 of the extension line D and a detection signal is outputted to the detector 12. If the telephone set A is removed at the rosette E or a connector F, the high frequency signal from the signal oscillator 11 of the monitor 13 is not detected by the detector 12. Thus, the MPU 10 does not read the signal from the detector 12. Then the MPU 10 discriminates it as the removal of the telephone set A to display the removal of the telephone set A at the reception telephone set G via the control line L4 of the operator circuit 9.
JP17088787A 1987-07-10 1987-07-10 Terminal equipment removal alarm system for telephone exchange Pending JPS6416053A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17088787A JPS6416053A (en) 1987-07-10 1987-07-10 Terminal equipment removal alarm system for telephone exchange

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17088787A JPS6416053A (en) 1987-07-10 1987-07-10 Terminal equipment removal alarm system for telephone exchange

Publications (1)

Publication Number Publication Date
JPS6416053A true JPS6416053A (en) 1989-01-19

Family

ID=15913159

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17088787A Pending JPS6416053A (en) 1987-07-10 1987-07-10 Terminal equipment removal alarm system for telephone exchange

Country Status (1)

Country Link
JP (1) JPS6416053A (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5890860A (en) * 1981-11-26 1983-05-30 Nec Corp Telephone set connection confirming system
JPS6238066A (en) * 1985-08-12 1987-02-19 Oki Electric Ind Co Ltd System for supervising telephone set connecting state

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5890860A (en) * 1981-11-26 1983-05-30 Nec Corp Telephone set connection confirming system
JPS6238066A (en) * 1985-08-12 1987-02-19 Oki Electric Ind Co Ltd System for supervising telephone set connecting state

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