JPS5437609A - Extension call system - Google Patents

Extension call system

Info

Publication number
JPS5437609A
JPS5437609A JP10455477A JP10455477A JPS5437609A JP S5437609 A JPS5437609 A JP S5437609A JP 10455477 A JP10455477 A JP 10455477A JP 10455477 A JP10455477 A JP 10455477A JP S5437609 A JPS5437609 A JP S5437609A
Authority
JP
Japan
Prior art keywords
extension call
call system
calling
telephone sets
extension
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.)
Granted
Application number
JP10455477A
Other languages
Japanese (ja)
Other versions
JPS5632822B2 (en
Inventor
Shinichi Shibata
Taiji Sato
Yoshiichi Sano
Takao 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.)
Toshiba Corp
Original Assignee
Toshiba Corp
Tokyo Shibaura 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 Toshiba Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP10455477A priority Critical patent/JPS5437609A/en
Publication of JPS5437609A publication Critical patent/JPS5437609A/en
Publication of JPS5632822B2 publication Critical patent/JPS5632822B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/002—Arrangements for interconnection not involving centralised switching with subscriber controlled access to a line, i.e. key telephone systems

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)

Abstract

PURPOSE:To prevent the calling tone from being broadcasted from other telephone sets in the general calling and the group calling, by stopping the extension call operation in case that two or more key telephone sets are connected in the extension circuit.
JP10455477A 1977-08-31 1977-08-31 Extension call system Granted JPS5437609A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10455477A JPS5437609A (en) 1977-08-31 1977-08-31 Extension call system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10455477A JPS5437609A (en) 1977-08-31 1977-08-31 Extension call system

Publications (2)

Publication Number Publication Date
JPS5437609A true JPS5437609A (en) 1979-03-20
JPS5632822B2 JPS5632822B2 (en) 1981-07-30

Family

ID=14383677

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10455477A Granted JPS5437609A (en) 1977-08-31 1977-08-31 Extension call system

Country Status (1)

Country Link
JP (1) JPS5437609A (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS498106A (en) * 1972-05-10 1974-01-24

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS498106A (en) * 1972-05-10 1974-01-24

Also Published As

Publication number Publication date
JPS5632822B2 (en) 1981-07-30

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