GB1232772A - - Google Patents

Info

Publication number
GB1232772A
GB1232772A GB1232772DA GB1232772A GB 1232772 A GB1232772 A GB 1232772A GB 1232772D A GB1232772D A GB 1232772DA GB 1232772 A GB1232772 A GB 1232772A
Authority
GB
United Kingdom
Prior art keywords
line
alarm
ringing
capacitor
relay
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
Other languages
English (en)
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 filed Critical
Publication of GB1232772A publication Critical patent/GB1232772A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
    • G08B29/12—Checking intermittently signalling or alarm systems
    • G08B29/123—Checking intermittently signalling or alarm systems of line circuits
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M11/00—Telephonic communication systems specially adapted for combination with other electrical systems
    • H04M11/04—Telephonic communication systems specially adapted for combination with other electrical systems with alarm systems, e.g. fire, police or burglar alarm systems
    • H04M11/045—Telephonic communication systems specially adapted for combination with other electrical systems with alarm systems, e.g. fire, police or burglar alarm systems using recorded signals, e.g. speech

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Security & Cryptography (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Alarm Systems (AREA)
GB1232772D 1969-01-03 1969-01-03 Expired GB1232772A (enExample)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB64869 1969-01-03

Publications (1)

Publication Number Publication Date
GB1232772A true GB1232772A (enExample) 1971-05-19

Family

ID=9708051

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1232772D Expired GB1232772A (enExample) 1969-01-03 1969-01-03

Country Status (1)

Country Link
GB (1) GB1232772A (enExample)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999005846A1 (en) * 1997-07-22 1999-02-04 Digital Security Controls Ltd. Security system alarm panel

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999005846A1 (en) * 1997-07-22 1999-02-04 Digital Security Controls Ltd. Security system alarm panel
US6226357B1 (en) 1997-07-22 2001-05-01 Digital Security Controls Ltd. Security system alarm panel

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Legal Events

Date Code Title Description
PS Patent sealed
PE20 Patent expired after termination of 20 years