JPS5624852A - Control system for key telephone system - Google Patents

Control system for key telephone system

Info

Publication number
JPS5624852A
JPS5624852A JP9986879A JP9986879A JPS5624852A JP S5624852 A JPS5624852 A JP S5624852A JP 9986879 A JP9986879 A JP 9986879A JP 9986879 A JP9986879 A JP 9986879A JP S5624852 A JPS5624852 A JP S5624852A
Authority
JP
Japan
Prior art keywords
line
current
key telephone
telephone system
office
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
JP9986879A
Other languages
Japanese (ja)
Other versions
JPS5939956B2 (en
Inventor
Masato Araki
Norio Saneyoshi
Akio Doi
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.)
Iwatsu Electric Co Ltd
Original Assignee
Iwatsu 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 Iwatsu Electric Co Ltd filed Critical Iwatsu Electric Co Ltd
Priority to JP9986879A priority Critical patent/JPS5939956B2/en
Publication of JPS5624852A publication Critical patent/JPS5624852A/en
Publication of JPS5939956B2 publication Critical patent/JPS5939956B2/en
Expired 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
    • H04M9/005—Arrangements for interconnection not involving centralised switching with subscriber controlled access to a line, i.e. key telephone systems with subscriber controlled access to an exchange line

Landscapes

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

Abstract

PURPOSE:To ensure both the office call and the extension call with the minimum number of insulated conductors and independently from each other for the key telephone system of the branch connection system, by forming the connecting cord for the office n circuit with 2n+2 pieces of insulated conductors. CONSTITUTION:Main wires L1 and L2 plus office call line 41 within the key telephone system form a DC loop each and also isolated from each other in terms of DC. These wires and line are furthermore connected to each other in terms of AC, and at the same time the branch connection is secured between line 41 and each of slave units 20 and 30. In addition, current supply means B2, CH10 and C10 are provided to the main device in order to supply the DC current to the neutral point of line 41. At the same time, the following means are provided to each slave unit: current extracting means CH21 and C21 which extract the DC from other neutral points of line 41; and control means 22, 23, 24 and 25 which give the necessary control each by the current extracted through the current extracting means.
JP9986879A 1979-08-07 1979-08-07 Control method for button telephone equipment Expired JPS5939956B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9986879A JPS5939956B2 (en) 1979-08-07 1979-08-07 Control method for button telephone equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9986879A JPS5939956B2 (en) 1979-08-07 1979-08-07 Control method for button telephone equipment

Publications (2)

Publication Number Publication Date
JPS5624852A true JPS5624852A (en) 1981-03-10
JPS5939956B2 JPS5939956B2 (en) 1984-09-27

Family

ID=14258778

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9986879A Expired JPS5939956B2 (en) 1979-08-07 1979-08-07 Control method for button telephone equipment

Country Status (1)

Country Link
JP (1) JPS5939956B2 (en)

Also Published As

Publication number Publication date
JPS5939956B2 (en) 1984-09-27

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