GB2205216B - Circuit arrangement for monitoring a telephone line - Google Patents

Circuit arrangement for monitoring a telephone line

Info

Publication number
GB2205216B
GB2205216B GB8810646A GB8810646A GB2205216B GB 2205216 B GB2205216 B GB 2205216B GB 8810646 A GB8810646 A GB 8810646A GB 8810646 A GB8810646 A GB 8810646A GB 2205216 B GB2205216 B GB 2205216B
Authority
GB
United Kingdom
Prior art keywords
monitoring
telephone line
circuit arrangement
telephone
arrangement
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 - Lifetime
Application number
GB8810646A
Other languages
English (en)
Other versions
GB2205216A (en
GB8810646D0 (en
Inventor
Werner Willhaus
Gerd Preikschat
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.)
Alcatel Lucent NV
Original Assignee
Alcatel NV
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 Alcatel NV filed Critical Alcatel NV
Publication of GB8810646D0 publication Critical patent/GB8810646D0/en
Publication of GB2205216A publication Critical patent/GB2205216A/en
Application granted granted Critical
Publication of GB2205216B publication Critical patent/GB2205216B/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/68—Circuit arrangements for preventing eavesdropping
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/66—Substation equipment, e.g. for use by subscribers with means for preventing unauthorised or fraudulent calling
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M17/00—Prepayment of wireline communication systems, wireless communication systems or telephone systems
    • H04M17/02—Coin-freed or check-freed systems, e.g. mobile- or card-operated phones, public telephones or booths
    • H04M17/023—Circuit arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Telephonic Communication Services (AREA)
  • Monitoring And Testing Of Exchanges (AREA)
GB8810646A 1987-05-09 1988-05-05 Circuit arrangement for monitoring a telephone line Expired - Lifetime GB2205216B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19873715580 DE3715580A1 (de) 1987-05-09 1987-05-09 Schaltungsanordnung zur ueberwachung einer fernsprechanschlussleitung

Publications (3)

Publication Number Publication Date
GB8810646D0 GB8810646D0 (en) 1988-06-08
GB2205216A GB2205216A (en) 1988-11-30
GB2205216B true GB2205216B (en) 1991-01-23

Family

ID=6327224

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8810646A Expired - Lifetime GB2205216B (en) 1987-05-09 1988-05-05 Circuit arrangement for monitoring a telephone line

Country Status (3)

Country Link
CH (1) CH674784A5 (de)
DE (1) DE3715580A1 (de)
GB (1) GB2205216B (de)

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4989239A (en) * 1989-09-15 1991-01-29 Mars Incorporated Method and apparatus for preventing pay telephone fraud and reducing handset vandalism
EP0454262A1 (de) * 1990-04-26 1991-10-30 Koninklijke KPN N.V. Elektronische Schaltung zur Meldung und/oder Verhinderung einer unbefugten Benutzung einer Fernsprechteilnehmerleitung
EP0474172A3 (en) * 1990-09-06 1993-03-03 Teletron Ltd. Telephone line monitoring apparatus and method
FR2672757B1 (fr) * 1991-02-08 1999-02-26 France Telecom Dispositif pour la detection d'un branchement non autorise sur une ligne telephonique d'abonne.
FR2674397A1 (fr) * 1991-03-20 1992-09-25 Regnier Marc Dispositif de surveillance d'une ligne d'abonne permettant la detection et l'enregistrement de signaux electriques lies a un branchement illicite.
EP0593120A1 (de) * 1992-10-14 1994-04-20 Koninklijke Philips Electronics N.V. Vorrichtung zum Feststellen der Inbestriebsetzung eines parallel angeschlossenen Telefonapparats
JPH0795284A (ja) * 1993-09-20 1995-04-07 Fujitsu Ltd 回線ブランチ検出・防止機能を備えた通信端末
DK11995A (da) * 1994-05-02 1995-11-03 Christian Henri Krause Sikringsenhed til telefonsystem
DE4421615C1 (de) * 1994-06-21 1996-12-05 Matthias Dipl Ing Viehmann Schaltungsanordnung zum Fremdeingriffschutz für das drahtgebundene Telefonnetz
DE19650007A1 (de) * 1996-11-23 1998-06-04 Ekkehard Dr Ing Dreetz Verfahren und Überwachungsvorrichtung zum Schutz von Telekommunikationswegen vor unberechtigtem Zugriff
GB2330270B (en) * 1997-10-09 2002-08-07 Inventec Corp Pay phone security protection circuit

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1278530B (de) * 1965-07-28 1968-09-26 Siemens Ag Schaltungsanordnung fuer Fernmeldevermittlungsanlagen, insbesondere von Fernsprechnebenstellenanlagen mit Pruefstromkreisen

Also Published As

Publication number Publication date
DE3715580C2 (de) 1992-02-06
GB2205216A (en) 1988-11-30
DE3715580A1 (de) 1988-11-24
CH674784A5 (de) 1990-07-13
GB8810646D0 (en) 1988-06-08

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Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19940505