GB1228647A - - Google Patents

Info

Publication number
GB1228647A
GB1228647A GB2768468A GB1228647DA GB1228647A GB 1228647 A GB1228647 A GB 1228647A GB 2768468 A GB2768468 A GB 2768468A GB 1228647D A GB1228647D A GB 1228647DA GB 1228647 A GB1228647 A GB 1228647A
Authority
GB
United Kingdom
Prior art keywords
oscillators
signals
oscillations
produced
frequencies
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
GB2768468A
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 GB1228647A publication Critical patent/GB1228647A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00—Individual registration on entry or exit
    • G07C9/00174—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys
    • G07C9/00658—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by passive electrical keys
    • G07C9/00714—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by passive electrical keys with passive electrical components, e.g. resistor, capacitor, inductor
    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00—Individual registration on entry or exit
    • G07C9/20—Individual registration on entry or exit involving the use of a pass
    • G07C9/28—Individual registration on entry or exit involving the use of a pass the pass enabling tracking or indicating presence
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING SYSTEMS, e.g. PERSONAL CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/22—Electrical actuation

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Burglar Alarm Systems (AREA)
  • Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
GB2768468A 1968-06-11 1968-06-11 Expired GB1228647A (enExample)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2768468 1968-06-11

Publications (1)

Publication Number Publication Date
GB1228647A true GB1228647A (enExample) 1971-04-15

Family

ID=10263615

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2768468A Expired GB1228647A (enExample) 1968-06-11 1968-06-11

Country Status (1)

Country Link
GB (1) GB1228647A (enExample)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4321586A (en) 1980-08-21 1982-03-23 Knogo Corporation Article theft detection

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4321586A (en) 1980-08-21 1982-03-23 Knogo Corporation Article theft detection
DE3128980A1 (de) * 1980-08-21 1982-04-08 Knogo Corp., 11801 Hicksville, N.Y. Verfahren und vorrichtung zum schutz von gegenstaenden gegen diebstahl

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Legal Events

Date Code Title Description
PS Patent sealed
PLNP Patent lapsed through nonpayment of renewal fees