GB1257430A - - Google Patents

Info

Publication number
GB1257430A
GB1257430A GB1257430DA GB1257430A GB 1257430 A GB1257430 A GB 1257430A GB 1257430D A GB1257430D A GB 1257430DA GB 1257430 A GB1257430 A GB 1257430A
Authority
GB
United Kingdom
Prior art keywords
alarm
transistor
photo
cell
circuit
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 GB1257430A publication Critical patent/GB1257430A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
    • G08B13/181—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using active radiation detection systems
    • G08B13/183—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using active radiation detection systems by interruption of a radiation beam or barrier

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Burglar Alarm Systems (AREA)
GB1257430D 1969-10-15 1970-05-19 Expired GB1257430A (enrdf_load_stackoverflow)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US86664969A 1969-10-15 1969-10-15

Publications (1)

Publication Number Publication Date
GB1257430A true GB1257430A (enrdf_load_stackoverflow) 1971-12-15

Family

ID=25348067

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1257430D Expired GB1257430A (enrdf_load_stackoverflow) 1969-10-15 1970-05-19

Country Status (3)

Country Link
US (1) US3636542A (enrdf_load_stackoverflow)
DE (1) DE2035125A1 (enrdf_load_stackoverflow)
GB (1) GB1257430A (enrdf_load_stackoverflow)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3967261A (en) * 1974-10-10 1976-06-29 Fudaley Solly L Proximity sensor with simultaneously active intermixed sensor types
US4021935A (en) * 1976-02-20 1977-05-10 Frank Witt Flight training hood
US4194192A (en) * 1978-12-11 1980-03-18 General Electric Company Alarm devices for interconnected multi-device systems
US4227190A (en) * 1979-02-26 1980-10-07 Kelley Jerry K Water alarm for monitoring floor moisture
US4940967A (en) * 1989-08-31 1990-07-10 Burle Technologies, Inc. Balanced digital infrared detector circuit
US5047749A (en) * 1990-04-03 1991-09-10 Tyco Industries, Inc. Passive remote photoelectric surveillance alarm with telescopic optics

Also Published As

Publication number Publication date
DE2035125A1 (de) 1971-04-22
US3636542A (en) 1972-01-18

Similar Documents

Publication Publication Date Title
GB1135287A (en) Improvements relating to minimum voltage warning apparatus
GB1401146A (en) Fire alarm system with remote central station
US3560950A (en) Warning signal for swinging doors
GB1257430A (enrdf_load_stackoverflow)
GB971225A (enrdf_load_stackoverflow)
GB831510A (en) Vehicle direction indicators
GB1351748A (en) Electric alarm systems
GB1280298A (en) Improvements in and relating to combustion detectors
GB1503140A (en) Voltage checking device
GB1052078A (en) Improvements in or relating to electrical generating systems
FR2087004A5 (en) Gas detector using semi-conductor with gasre
GB827993A (en) Portable containers provided with theft alarm devices
GB775424A (en) Improvements in or relating to cases, bags, boxes or the like
GB999757A (en) Improvements in alarm annunciators
GB1160760A (en) Automatic Fire Alarm System
FR1503894A (fr) Perfectionnements aux installations électriques d'alarme et de surveillance
GB1316518A (en) Selectively controlled alarm
FR2339198A1 (fr) Reveil electrique utilise comme moyen d'alarme
GB1232700A (enrdf_load_stackoverflow)
GB913973A (en) Improvements in or relating to burglar and like alarms
GB923878A (en) Control means for flashing electric signal lamp systems
GB1456681A (en) Loop alarm apparatus
GB977769A (en) Improvements in or relating to electrical circuits for use with temperature responsive devices
ES381761A1 (es) Mejoras introducidas en detectores de humos por ionizacion.
GB1161004A (en) Improvements relating to Monitoring Circuits

Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PLNP Patent lapsed through nonpayment of renewal fees