JPS55136784A - Communication circuit of telephone exchange - Google Patents

Communication circuit of telephone exchange

Info

Publication number
JPS55136784A
JPS55136784A JP4463879A JP4463879A JPS55136784A JP S55136784 A JPS55136784 A JP S55136784A JP 4463879 A JP4463879 A JP 4463879A JP 4463879 A JP4463879 A JP 4463879A JP S55136784 A JPS55136784 A JP S55136784A
Authority
JP
Japan
Prior art keywords
communication
mercury
relay
communication circuit
attenuation
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
JP4463879A
Other languages
Japanese (ja)
Other versions
JPS6019874B2 (en
Inventor
Yoshiaki Endo
Mikio Doi
Tatsuo Uchida
Fumiaki Kusunoki
Masao Umagami
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.)
Fujitsu Ltd
Hitachi Ltd
NEC Corp
Nippon Telegraph and Telephone Corp
Oki Electric Industry Co Ltd
Original Assignee
Fujitsu Ltd
Hitachi Ltd
NEC Corp
Nippon Telegraph and Telephone Corp
Oki Electric Industry Co Ltd
Nippon 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 Fujitsu Ltd, Hitachi Ltd, NEC Corp, Nippon Telegraph and Telephone Corp, Oki Electric Industry Co Ltd, Nippon Electric Co Ltd filed Critical Fujitsu Ltd
Priority to JP4463879A priority Critical patent/JPS6019874B2/en
Publication of JPS55136784A publication Critical patent/JPS55136784A/en
Publication of JPS6019874B2 publication Critical patent/JPS6019874B2/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Prepayment Telephone Systems (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

PURPOSE:To enable to directly connect the mercury relay in series with the communication line, by preventing the attenuation of communication through the connection of capacitor in parallel with the communication line between mercury relays and using the mercury relay having the characteristics similar to the normal A position relay. CONSTITUTION:The DC signal delivered from the exchanger EX is identified with the telephone set loop and the mercury relay LP or RV, and after that, the frequency outside the communication band delivered from the public telephone set TEL is identified with the frequency detection circuit via the AC signal pick up circuit A. In this case, the capacitor C is connected between the mercury relays LP and RV connected in series with the communication lines A1,A2;B1,B2 to avoid the attenuation of the communication.
JP4463879A 1979-04-12 1979-04-12 telephone exchange call circuit Expired JPS6019874B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4463879A JPS6019874B2 (en) 1979-04-12 1979-04-12 telephone exchange call circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4463879A JPS6019874B2 (en) 1979-04-12 1979-04-12 telephone exchange call circuit

Publications (2)

Publication Number Publication Date
JPS55136784A true JPS55136784A (en) 1980-10-24
JPS6019874B2 JPS6019874B2 (en) 1985-05-18

Family

ID=12696964

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4463879A Expired JPS6019874B2 (en) 1979-04-12 1979-04-12 telephone exchange call circuit

Country Status (1)

Country Link
JP (1) JPS6019874B2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0210387Y2 (en) * 1986-01-29 1990-03-14

Also Published As

Publication number Publication date
JPS6019874B2 (en) 1985-05-18

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