GB507923A - Improvements in or relating to electric signalling equipment - Google Patents

Improvements in or relating to electric signalling equipment

Info

Publication number
GB507923A
GB507923A GB3556637A GB3556637A GB507923A GB 507923 A GB507923 A GB 507923A GB 3556637 A GB3556637 A GB 3556637A GB 3556637 A GB3556637 A GB 3556637A GB 507923 A GB507923 A GB 507923A
Authority
GB
United Kingdom
Prior art keywords
alarm
portable
impulses
over
equipment
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
GB3556637A
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB3556637A priority Critical patent/GB507923A/en
Publication of GB507923A publication Critical patent/GB507923A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B27/00—Alarm systems in which the alarm condition is signalled from a central station to a plurality of substations
    • G08B27/001—Signalling to an emergency team, e.g. firemen
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B27/00—Alarm systems in which the alarm condition is signalled from a central station to a plurality of substations
    • G08B27/006—Alarm systems in which the alarm condition is signalled from a central station to a plurality of substations with transmission via telephone network

Landscapes

  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Alarm Systems (AREA)

Abstract

507,923. Electric signalling systems. STANDARD TELEPHONES & CABLES, Ltd., and BOWSHER, E. A. H. Dec. 22, 1937, No. 35566. Drawings to Specification. [Class 40 (i)] A portable electric alarm unit, more particularly for use by air-raid wardens, comprises an alarm device, e.g. a bell, a device responsive to signals transmitted over the electricity supply network for operating the alarm and a manually-operated device such as a pushbutton for terminating the operation of the alarm. The equipment is contained in a portable case and is provided with a connecting lead and plug which may be inserted in a wall or lamp socket of the supply network. The system may be of the type described in Specification 495,057, wherein time-spaced impulses are transmitted over the network and effect operation at the receiver over the contacts of a rotary distributer; in this case, the portable equipment also includes the distributer. Firemen's and warden's alarms may be operated over the same systems by differently spaced impulses; alternatively, in a system wherein distributers are dispensed with, impulses of different polarity are used.
GB3556637A 1937-12-22 1937-12-22 Improvements in or relating to electric signalling equipment Expired GB507923A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB3556637A GB507923A (en) 1937-12-22 1937-12-22 Improvements in or relating to electric signalling equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3556637A GB507923A (en) 1937-12-22 1937-12-22 Improvements in or relating to electric signalling equipment

Publications (1)

Publication Number Publication Date
GB507923A true GB507923A (en) 1939-06-22

Family

ID=10379156

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3556637A Expired GB507923A (en) 1937-12-22 1937-12-22 Improvements in or relating to electric signalling equipment

Country Status (1)

Country Link
GB (1) GB507923A (en)

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