JPS52130221A - Ringing detection circuit in telephone exchanger - Google Patents

Ringing detection circuit in telephone exchanger

Info

Publication number
JPS52130221A
JPS52130221A JP4704776A JP4704776A JPS52130221A JP S52130221 A JPS52130221 A JP S52130221A JP 4704776 A JP4704776 A JP 4704776A JP 4704776 A JP4704776 A JP 4704776A JP S52130221 A JPS52130221 A JP S52130221A
Authority
JP
Japan
Prior art keywords
detection circuit
ringing detection
telephone exchanger
ringing
exchanger
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
JP4704776A
Other languages
Japanese (ja)
Other versions
JPS5744074B2 (en
Inventor
Masato Fujisawa
Mitsutoshi Ayano
Eiji Minamitani
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
Original Assignee
Fujitsu 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 filed Critical Fujitsu Ltd
Priority to JP4704776A priority Critical patent/JPS52130221A/en
Publication of JPS52130221A publication Critical patent/JPS52130221A/en
Publication of JPS5744074B2 publication Critical patent/JPS5744074B2/ja
Granted legal-status Critical Current

Links

Abstract

PURPOSE: To enable small size and long life detection circuit, by converting the ringing signal current transmitted via main line into the logic level by utilizing photo couplers.
COPYRIGHT: (C)1977,JPO&Japio
JP4704776A 1976-04-24 1976-04-24 Ringing detection circuit in telephone exchanger Granted JPS52130221A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4704776A JPS52130221A (en) 1976-04-24 1976-04-24 Ringing detection circuit in telephone exchanger

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4704776A JPS52130221A (en) 1976-04-24 1976-04-24 Ringing detection circuit in telephone exchanger

Publications (2)

Publication Number Publication Date
JPS52130221A true JPS52130221A (en) 1977-11-01
JPS5744074B2 JPS5744074B2 (en) 1982-09-18

Family

ID=12764244

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4704776A Granted JPS52130221A (en) 1976-04-24 1976-04-24 Ringing detection circuit in telephone exchanger

Country Status (1)

Country Link
JP (1) JPS52130221A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5484909A (en) * 1977-12-13 1979-07-06 Fujitsu Ltd Signal detection system
JPS6010896A (en) * 1983-06-29 1985-01-21 Matsushita Electric Ind Co Ltd Trunk line circuit

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5118407A (en) * 1974-07-10 1976-02-14 Nippon Electric Co DAIYARU PARUSUSHUSEIKAIRO

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5118407A (en) * 1974-07-10 1976-02-14 Nippon Electric Co DAIYARU PARUSUSHUSEIKAIRO

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5484909A (en) * 1977-12-13 1979-07-06 Fujitsu Ltd Signal detection system
JPS573273B2 (en) * 1977-12-13 1982-01-20
JPS6010896A (en) * 1983-06-29 1985-01-21 Matsushita Electric Ind Co Ltd Trunk line circuit
JPH0318797B2 (en) * 1983-06-29 1991-03-13 Matsushita Electric Ind Co Ltd

Also Published As

Publication number Publication date
JPS5744074B2 (en) 1982-09-18

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