FR2346928A1 - Subscriber telephone line loop state verification - uses detector with resistance wire coils between lines to prevent short circuit - Google Patents

Subscriber telephone line loop state verification - uses detector with resistance wire coils between lines to prevent short circuit

Info

Publication number
FR2346928A1
FR2346928A1 FR7609147A FR7609147A FR2346928A1 FR 2346928 A1 FR2346928 A1 FR 2346928A1 FR 7609147 A FR7609147 A FR 7609147A FR 7609147 A FR7609147 A FR 7609147A FR 2346928 A1 FR2346928 A1 FR 2346928A1
Authority
FR
France
Prior art keywords
resistance wire
telephone line
loop state
coils
lines
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
FR7609147A
Other languages
French (fr)
Other versions
FR2346928B1 (en
Inventor
Kevork Kevorkian
Jean-Pierre Le Pabic
Hubert Jean Gerard Nachon
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.)
Thales SA
Original Assignee
Le Materiel Telephonique Thomson CSF
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 Le Materiel Telephonique Thomson CSF filed Critical Le Materiel Telephonique Thomson CSF
Priority to FR7609147A priority Critical patent/FR2346928A1/en
Publication of FR2346928A1 publication Critical patent/FR2346928A1/en
Application granted granted Critical
Publication of FR2346928B1 publication Critical patent/FR2346928B1/fr
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/18—Automatic or semi-automatic exchanges with means for reducing interference or noise; with means for reducing effects due to line faults with means for protecting lines
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M19/00—Current supply arrangements for telephone systems
    • H04M19/001—Current supply source at the exchanger providing current to substations

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Monitoring And Testing Of Exchanges (AREA)

Abstract

The loop state of a subscriber telephone line is verified using coils connected between the lines and detector circuit. The use of series resistors for short circuit protection is eliminated by coils using resistance wire. A telephone line is connected (1, 2) to a subscriber line equipment and conductors (5, 6) permit connection to a switching circuit (4) via capacitors (7, 8). Coils (12, 14) of resistance wire connect a battery (10) to the conductor circuit whose loop state is sensed by a detector (20) also connected to the switching circuit. A third coil (22) with diode limiter (28) is coupled to the coils to enable tone signals to be sent to the subscriber. A fourth winding (24) in a wheatstone bridge (26) series temperature.
FR7609147A 1976-03-30 1976-03-30 Subscriber telephone line loop state verification - uses detector with resistance wire coils between lines to prevent short circuit Granted FR2346928A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR7609147A FR2346928A1 (en) 1976-03-30 1976-03-30 Subscriber telephone line loop state verification - uses detector with resistance wire coils between lines to prevent short circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR7609147A FR2346928A1 (en) 1976-03-30 1976-03-30 Subscriber telephone line loop state verification - uses detector with resistance wire coils between lines to prevent short circuit

Publications (2)

Publication Number Publication Date
FR2346928A1 true FR2346928A1 (en) 1977-10-28
FR2346928B1 FR2346928B1 (en) 1981-05-29

Family

ID=9171124

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7609147A Granted FR2346928A1 (en) 1976-03-30 1976-03-30 Subscriber telephone line loop state verification - uses detector with resistance wire coils between lines to prevent short circuit

Country Status (1)

Country Link
FR (1) FR2346928A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0295822A2 (en) * 1987-06-15 1988-12-21 Nortel Networks Corporation Subscriber line interface circuit and transformer therefor

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0295822A2 (en) * 1987-06-15 1988-12-21 Nortel Networks Corporation Subscriber line interface circuit and transformer therefor
EP0295822A3 (en) * 1987-06-15 1990-10-31 Nortel Networks Corporation Subscriber line interface circuit and transformer therefor

Also Published As

Publication number Publication date
FR2346928B1 (en) 1981-05-29

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Legal Events

Date Code Title Description
ST Notification of lapse