Title:
Intrusion detection system
United States Patent 3309689
US Patent References:
Photosensitive device
- - 1877279
Photo-electric system
- - 2016036
Photoelectric burglar alarm system
- - 2227147
Signal deviation warning system
- - 2656527
Light controlled electrical system and relay therefor
- - 3089065
Photosensitive device
- - 1877279
Photo-electric system
- - 2016036
Photoelectric burglar alarm system
- - 2227147
Signal deviation warning system
- - 2656527
Light controlled electrical system and relay therefor
- - 3089065
Inventors:
Keeney, Clare G.
Publication Date:
03/14/1967
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Export Citation:
Assignee:
SYLVANIA ELECTRIC PROD
Primary Class:
Other Classes:
250/221
International Classes:
G08B13/189