GB8810646D0 - Circuit arrangement for monitoring telephone line - Google Patents

Circuit arrangement for monitoring telephone line

Info

Publication number
GB8810646D0
GB8810646D0 GB888810646A GB8810646A GB8810646D0 GB 8810646 D0 GB8810646 D0 GB 8810646D0 GB 888810646 A GB888810646 A GB 888810646A GB 8810646 A GB8810646 A GB 8810646A GB 8810646 D0 GB8810646 D0 GB 8810646D0
Authority
GB
United Kingdom
Prior art keywords
telephone line
circuit arrangement
monitoring telephone
monitoring
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.)
Granted
Application number
GB888810646A
Other versions
GB2205216A (en
GB2205216B (en
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 (en) 1987-05-09 1987-05-09 CIRCUIT ARRANGEMENT FOR MONITORING A TELEPHONE CONNECTION LINE

Publications (3)

Publication Number Publication Date
GB8810646D0 true GB8810646D0 (en) 1988-06-08
GB2205216A GB2205216A (en) 1988-11-30
GB2205216B 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 (en)
DE (1) DE3715580A1 (en)
GB (1) GB2205216B (en)

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 (en) * 1990-04-26 1991-10-30 Koninklijke KPN N.V. Electronic circuit for signalling and/or preventing improper use of a telephone subscriber line
EP0474172A3 (en) * 1990-09-06 1993-03-03 Teletron Ltd. Telephone line monitoring apparatus and method
FR2672757B1 (en) * 1991-02-08 1999-02-26 France Telecom DEVICE FOR DETECTING AN UNAUTHORIZED CONNECTION ON A SUBSCRIBER TELEPHONE LINE.
FR2674397A1 (en) * 1991-03-20 1992-09-25 Regnier Marc Device for monitoring a subscriber line allowing detection and recording of electrical signals related to an illicit tapping
SG44843A1 (en) * 1992-10-14 1997-12-19 Philips Electronics Nv Device for detecting the activation of a parallel connected telephone set
JPH0795284A (en) * 1993-09-20 1995-04-07 Fujitsu Ltd Communications terminal provided with function for detecting and preventing lie branching
DK11995A (en) * 1994-05-02 1995-11-03 Christian Henri Krause Telephone system fuse
DE4421615C1 (en) * 1994-06-21 1996-12-05 Matthias Dipl Ing Viehmann Circuit arrangement for external interference protection for the wired telephone network
DE19650007A1 (en) * 1996-11-23 1998-06-04 Ekkehard Dr Ing Dreetz Telecommunication path protection method
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 (en) * 1965-07-28 1968-09-26 Siemens Ag Circuit arrangement for telecommunication switching systems, in particular of telephone extension systems with test circuits

Also Published As

Publication number Publication date
GB2205216A (en) 1988-11-30
DE3715580C2 (en) 1992-02-06
DE3715580A1 (en) 1988-11-24
CH674784A5 (en) 1990-07-13
GB2205216B (en) 1991-01-23

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Legal Events

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

Effective date: 19940505