JPS51147905A - Busy indication circuit in a switch-box type additional telephone set - Google Patents

Busy indication circuit in a switch-box type additional telephone set

Info

Publication number
JPS51147905A
JPS51147905A JP50072545A JP7254575A JPS51147905A JP S51147905 A JPS51147905 A JP S51147905A JP 50072545 A JP50072545 A JP 50072545A JP 7254575 A JP7254575 A JP 7254575A JP S51147905 A JPS51147905 A JP S51147905A
Authority
JP
Japan
Prior art keywords
switch
busy indication
telephone set
box type
indication circuit
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
JP50072545A
Other languages
Japanese (ja)
Inventor
Kiyoshi Makita
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to JP50072545A priority Critical patent/JPS51147905A/en
Publication of JPS51147905A publication Critical patent/JPS51147905A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/60—Semi-automatic systems, i.e. in which the numerical selection of the outgoing line is under the control of an operator
    • H04M3/62—Keyboard equipment

Landscapes

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

Abstract

PURPOSE:A busy indication circuit whereby a busy indication can be performed by utilizing the current supplied to a telephone from a switch-board, without affecting to telephone service.
JP50072545A 1975-06-14 1975-06-14 Busy indication circuit in a switch-box type additional telephone set Pending JPS51147905A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP50072545A JPS51147905A (en) 1975-06-14 1975-06-14 Busy indication circuit in a switch-box type additional telephone set

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP50072545A JPS51147905A (en) 1975-06-14 1975-06-14 Busy indication circuit in a switch-box type additional telephone set

Publications (1)

Publication Number Publication Date
JPS51147905A true JPS51147905A (en) 1976-12-18

Family

ID=13492424

Family Applications (1)

Application Number Title Priority Date Filing Date
JP50072545A Pending JPS51147905A (en) 1975-06-14 1975-06-14 Busy indication circuit in a switch-box type additional telephone set

Country Status (1)

Country Link
JP (1) JPS51147905A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0236244U (en) * 1988-09-02 1990-03-08

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0236244U (en) * 1988-09-02 1990-03-08

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