FR2362456A1 - Centralised supervisory and alarm system for remote subscriber units - uses three signal transmission system to detect and verify correct alarm condition - Google Patents

Centralised supervisory and alarm system for remote subscriber units - uses three signal transmission system to detect and verify correct alarm condition

Info

Publication number
FR2362456A1
FR2362456A1 FR7625233A FR7625233A FR2362456A1 FR 2362456 A1 FR2362456 A1 FR 2362456A1 FR 7625233 A FR7625233 A FR 7625233A FR 7625233 A FR7625233 A FR 7625233A FR 2362456 A1 FR2362456 A1 FR 2362456A1
Authority
FR
France
Prior art keywords
signals
supervisory
central
signal transmission
transformer
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
FR7625233A
Other languages
French (fr)
Other versions
FR2362456B1 (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.)
Fichet Bauche SA
Original Assignee
Fichet Bauche SA
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 Fichet Bauche SA filed Critical Fichet Bauche SA
Priority to FR7625233A priority Critical patent/FR2362456A1/en
Publication of FR2362456A1 publication Critical patent/FR2362456A1/en
Application granted granted Critical
Publication of FR2362456B1 publication Critical patent/FR2362456B1/fr
Granted 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
    • G08B29/02—Monitoring continuously signalling or alarm systems
    • G08B29/06—Monitoring of the line circuits, e.g. signalling of line faults
    • G08B29/08—Signalling of tampering with the line circuit
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B25/00—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems
    • G08B25/01—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium
    • G08B25/08—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium using communication transmission lines

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Alarm Systems (AREA)

Abstract

The supervisory and alarm system controls from a central post a number of remote installations via signals transmitted over telephone wires. Interruption of a signal during a predetermined time period actuates an alaram. The time also transmits during this period a succession of irregular signals which are designed to counteract fraudulent recorded signal transmission. In the central supervisory unit there is a section for each subscriber on which is mounted a differential transformer. Through this transformer to the subscriber circuits are applied signals from the incoming line. The transformer also introduces into the circuits the succession of irregular signals emanating from a central source. The differential transformer ensures during processing of the output signals that the effect of irregular signals from the central source are minimised. The subscriber circuits in the central unit have an amplifier with automatic gain control amplifying the frequency of the irregular signals.
FR7625233A 1976-08-19 1976-08-19 Centralised supervisory and alarm system for remote subscriber units - uses three signal transmission system to detect and verify correct alarm condition Granted FR2362456A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR7625233A FR2362456A1 (en) 1976-08-19 1976-08-19 Centralised supervisory and alarm system for remote subscriber units - uses three signal transmission system to detect and verify correct alarm condition

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR7625233A FR2362456A1 (en) 1976-08-19 1976-08-19 Centralised supervisory and alarm system for remote subscriber units - uses three signal transmission system to detect and verify correct alarm condition

Publications (2)

Publication Number Publication Date
FR2362456A1 true FR2362456A1 (en) 1978-03-17
FR2362456B1 FR2362456B1 (en) 1982-08-20

Family

ID=9177010

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7625233A Granted FR2362456A1 (en) 1976-08-19 1976-08-19 Centralised supervisory and alarm system for remote subscriber units - uses three signal transmission system to detect and verify correct alarm condition

Country Status (1)

Country Link
FR (1) FR2362456A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2551280A1 (en) * 1983-08-25 1985-03-01 Gotanda Motohiro BUILDING MONITORING DEVICE

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2551280A1 (en) * 1983-08-25 1985-03-01 Gotanda Motohiro BUILDING MONITORING DEVICE

Also Published As

Publication number Publication date
FR2362456B1 (en) 1982-08-20

Similar Documents

Publication Publication Date Title
US4591834A (en) Intrusion detecting apparatus with zone identification and with noise interference discrimination
JP2750128B2 (en) Dial tone detector
US3930246A (en) Electrical alarm system
US2946852A (en) Automatic telephone answering and message-recording system
GR3030894T3 (en) Selective system scan for multizone radiotelephone subscriber units.
FR2362456A1 (en) Centralised supervisory and alarm system for remote subscriber units - uses three signal transmission system to detect and verify correct alarm condition
US3598919A (en) Pre-recorded alarm-reporting system and control element therefor
US3707651A (en) Frequency shifted modulated carrier protective relaying system with amplitude modulated voice communication
ES375107A1 (en) Supervisory system for unattended repeaters
GB1452024A (en) Electronic multi-media programmer
FR2295506A1 (en) Remote alarm transmission system - monitors integrity of telephone pilot wires and system by transmission of simulated alarm signals at predetermined time periods
US3482045A (en) Automatic telephone alarm with voice message transmitted upon line polarity reversal
GB1120455A (en) Remote-controlled alarm networks
US3560657A (en) Automatic warning system
JPS56106494A (en) Method and device for howling prevention of loudspeaker
US2401024A (en) Control system
US2258966A (en) Control of transmission in two-way signaling systems
US5452363A (en) Direction sensing microphone system using time differential
JPS56140515A (en) Muting circuit
FR2395557A1 (en) Public telephone call box burglary detection system - uses telephone line to transmit alarm signals to exchange
JPS5511673A (en) Automatic tone adjusting telephone set
GB1450893A (en) Sound distribution systems
EP0091276A3 (en) Sound pattern discrimination system
JP2757968B2 (en) Wireless operator absence detector
GB824065A (en) Improvements in or relating to a method of and a device for eliminating spurious information in a signal transmission system

Legal Events

Date Code Title Description
ST Notification of lapse