JPS5333505A - Multi-frequency signal output monitor system for key telephone set - Google Patents

Multi-frequency signal output monitor system for key telephone set

Info

Publication number
JPS5333505A
JPS5333505A JP10777476A JP10777476A JPS5333505A JP S5333505 A JPS5333505 A JP S5333505A JP 10777476 A JP10777476 A JP 10777476A JP 10777476 A JP10777476 A JP 10777476A JP S5333505 A JPS5333505 A JP S5333505A
Authority
JP
Japan
Prior art keywords
frequency signal
key telephone
signal output
telephone set
monitor system
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
JP10777476A
Other languages
Japanese (ja)
Inventor
Teruhiko Endo
Mitsugi Saida
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 JP10777476A priority Critical patent/JPS5333505A/en
Publication of JPS5333505A publication Critical patent/JPS5333505A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/26—Devices for calling a subscriber
    • H04M1/30—Devices which can set up and transmit only one digit at a time
    • H04M1/50—Devices which can set up and transmit only one digit at a time by generating or selecting currents of predetermined frequencies or combinations of frequencies

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)

Abstract

PURPOSE:To prevent the malfunction for a key telephone receiver by outputting a multi-frequency signal for a prescribed time or more.
JP10777476A 1976-09-10 1976-09-10 Multi-frequency signal output monitor system for key telephone set Pending JPS5333505A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10777476A JPS5333505A (en) 1976-09-10 1976-09-10 Multi-frequency signal output monitor system for key telephone set

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10777476A JPS5333505A (en) 1976-09-10 1976-09-10 Multi-frequency signal output monitor system for key telephone set

Publications (1)

Publication Number Publication Date
JPS5333505A true JPS5333505A (en) 1978-03-29

Family

ID=14467663

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10777476A Pending JPS5333505A (en) 1976-09-10 1976-09-10 Multi-frequency signal output monitor system for key telephone set

Country Status (1)

Country Link
JP (1) JPS5333505A (en)

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