FR2464604B1 - Circuit de detection de boucle pour systemes telephoniques - Google Patents

Circuit de detection de boucle pour systemes telephoniques

Info

Publication number
FR2464604B1
FR2464604B1 FR8019048A FR8019048A FR2464604B1 FR 2464604 B1 FR2464604 B1 FR 2464604B1 FR 8019048 A FR8019048 A FR 8019048A FR 8019048 A FR8019048 A FR 8019048A FR 2464604 B1 FR2464604 B1 FR 2464604B1
Authority
FR
France
Prior art keywords
detection circuit
telephone systems
loop detection
loop
telephone
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.)
Expired
Application number
FR8019048A
Other languages
English (en)
Other versions
FR2464604A1 (fr
Inventor
Junjiro Kitano
Tetsuo Takeshita
Kazuo Hamazato
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.)
Hitachi Ltd
Original Assignee
Hitachi 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 Hitachi Ltd filed Critical Hitachi Ltd
Publication of FR2464604A1 publication Critical patent/FR2464604A1/fr
Application granted granted Critical
Publication of FR2464604B1 publication Critical patent/FR2464604B1/fr
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/2272—Subscriber line supervision circuits, e.g. call detection circuits

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Devices For Supply Of Signal Current (AREA)
FR8019048A 1979-09-05 1980-09-03 Circuit de detection de boucle pour systemes telephoniques Expired FR2464604B1 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11280679A JPS5637793A (en) 1979-09-05 1979-09-05 Loop detecting circuit

Publications (2)

Publication Number Publication Date
FR2464604A1 FR2464604A1 (fr) 1981-03-06
FR2464604B1 true FR2464604B1 (fr) 1987-10-09

Family

ID=14595989

Family Applications (1)

Application Number Title Priority Date Filing Date
FR8019048A Expired FR2464604B1 (fr) 1979-09-05 1980-09-03 Circuit de detection de boucle pour systemes telephoniques

Country Status (7)

Country Link
US (1) US4360709A (fr)
JP (1) JPS5637793A (fr)
BE (1) BE885083A (fr)
CA (1) CA1160778A (fr)
DE (1) DE3033037C2 (fr)
FR (1) FR2464604B1 (fr)
GB (1) GB2058519B (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4439634A (en) * 1982-04-02 1984-03-27 Gte Automatic Electric Incorporated Carrier subscriber telephone off-hook detector
US4631362A (en) * 1984-09-27 1986-12-23 At&T Bell Laboratories Low resistance origination scan circuit
US4731827A (en) * 1984-10-29 1988-03-15 David Systems, Inc. Interswitch line circuit
HU192925B (en) * 1985-03-29 1987-08-28 Bhg Hiradastech Vallalat Circuit arrangement for realizing circuit sensing state of loop, in particular to processor controlled digital sub-exchanges
US4827505A (en) * 1985-08-20 1989-05-02 Fujitsu Limited Subscriber line interface circuit
US8861337B2 (en) 2012-05-07 2014-10-14 Tesla Motors, Inc. Robust communications in electrically noisy environments

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1200909A (en) * 1967-11-30 1970-08-05 Standard Telephones Cables Ltd Loop current detector
BE754235A (fr) * 1969-08-05 1970-12-31 Western Electric Co Circuit de supervision pour lignes telephoniques
US3781571A (en) * 1971-12-06 1973-12-25 Int Standard Electric Corp Loop current detector
GB1563803A (en) * 1975-11-26 1980-04-02 Post Office Telecommunications transmission and signalling curcuits
US4099032A (en) * 1977-03-25 1978-07-04 Wescom, Inc. Loop current detector
US4203012A (en) * 1977-07-14 1980-05-13 Boxall Frank S Hybrid circuit using current mirror circuits
JPS55100778A (en) * 1979-01-26 1980-07-31 Nippon Telegr & Teleph Corp <Ntt> Answer supervisory system

Also Published As

Publication number Publication date
JPS5637793A (en) 1981-04-11
FR2464604A1 (fr) 1981-03-06
BE885083A (fr) 1980-12-31
GB2058519B (en) 1984-01-25
CA1160778A (fr) 1984-01-17
DE3033037A1 (de) 1981-04-09
US4360709A (en) 1982-11-23
GB2058519A (en) 1981-04-08
DE3033037C2 (de) 1987-05-07

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Legal Events

Date Code Title Description
TP Transmission of property
ST Notification of lapse