CA1084137A - Methode et appareil de surveillance electronique de zones bien delimitees - Google Patents

Methode et appareil de surveillance electronique de zones bien delimitees

Info

Publication number
CA1084137A
CA1084137A CA287,373A CA287373A CA1084137A CA 1084137 A CA1084137 A CA 1084137A CA 287373 A CA287373 A CA 287373A CA 1084137 A CA1084137 A CA 1084137A
Authority
CA
Canada
Prior art keywords
signals
output
frequency
receiver
control zone
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
CA287,373A
Other languages
English (en)
Inventor
Robert D. Williamson
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to CA287,373A priority Critical patent/CA1084137A/fr
Application granted granted Critical
Publication of CA1084137A publication Critical patent/CA1084137A/fr
Expired legal-status Critical Current

Links

Landscapes

  • Burglar Alarm Systems (AREA)
CA287,373A 1977-09-23 1977-09-23 Methode et appareil de surveillance electronique de zones bien delimitees Expired CA1084137A (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CA287,373A CA1084137A (fr) 1977-09-23 1977-09-23 Methode et appareil de surveillance electronique de zones bien delimitees

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CA287,373A CA1084137A (fr) 1977-09-23 1977-09-23 Methode et appareil de surveillance electronique de zones bien delimitees

Publications (1)

Publication Number Publication Date
CA1084137A true CA1084137A (fr) 1980-08-19

Family

ID=4109608

Family Applications (1)

Application Number Title Priority Date Filing Date
CA287,373A Expired CA1084137A (fr) 1977-09-23 1977-09-23 Methode et appareil de surveillance electronique de zones bien delimitees

Country Status (1)

Country Link
CA (1) CA1084137A (fr)

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Legal Events

Date Code Title Description
MKEX Expiry