JPS6474891A - Telephone exchange - Google Patents

Telephone exchange

Info

Publication number
JPS6474891A
JPS6474891A JP23308587A JP23308587A JPS6474891A JP S6474891 A JPS6474891 A JP S6474891A JP 23308587 A JP23308587 A JP 23308587A JP 23308587 A JP23308587 A JP 23308587A JP S6474891 A JPS6474891 A JP S6474891A
Authority
JP
Japan
Prior art keywords
sets
transmission
telephone
single telephone
telephone exchange
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
JP23308587A
Other languages
Japanese (ja)
Inventor
Masayuki Tsurusaki
Hiroshi Mano
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
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 filed Critical Toshiba Corp
Priority to JP23308587A priority Critical patent/JPS6474891A/en
Publication of JPS6474891A publication Critical patent/JPS6474891A/en
Pending legal-status Critical Current

Links

Landscapes

  • Interface Circuits In Exchanges (AREA)

Abstract

PURPOSE:To allow an extension extending distance to be long by providing a single telephone set interface equipment between a telephone set and a main equipment when one or plural numbers of single telephone sets are connected to a main equipment of a telephone exchange. CONSTITUTION:The telephone exchange is composed of the main equipment 1 of the telephone exchange, interface circuits 15 and 16 for the several numbers of the single telephone sets to be respectively connected through two-wire circuit for ping-pong transmission and single telephone sets 11-14 to be connected through an analog two-wire circuit to these circuits at every two sets. Thus, when the extension is extended, transmission between equipments is executed by digital data since the interface equipment is moved together with the single telephone set and accordingly, the transmission loss of a line does not go to be a problem. Since a ping-pong system is adopted as the transmission system of the digital data, two lines are enough as a circuit between the equipments and difficulty to supply a current due to extension extending is not generated.
JP23308587A 1987-09-17 1987-09-17 Telephone exchange Pending JPS6474891A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP23308587A JPS6474891A (en) 1987-09-17 1987-09-17 Telephone exchange

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP23308587A JPS6474891A (en) 1987-09-17 1987-09-17 Telephone exchange

Publications (1)

Publication Number Publication Date
JPS6474891A true JPS6474891A (en) 1989-03-20

Family

ID=16949560

Family Applications (1)

Application Number Title Priority Date Filing Date
JP23308587A Pending JPS6474891A (en) 1987-09-17 1987-09-17 Telephone exchange

Country Status (1)

Country Link
JP (1) JPS6474891A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10346581B4 (en) * 2003-01-14 2007-12-27 Renesas Technology Corp. Method for producing a semiconductor device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10346581B4 (en) * 2003-01-14 2007-12-27 Renesas Technology Corp. Method for producing a semiconductor device

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