CAPACITY--OPERATED PROTECTIVE SYSTEM
Patent
·
OSTI ID:4016293
A system for protecting a security area from intruders is described. The system is comprised of a sensing capacitor having first and second plates disposed in the security area. The detector is comprised of a transistor two- stage astable multivibrator with rectifier means for producing a proportional d-c output signal. The system also contains a monitor disposed at a location removed from the security area that responds to only sudden changes in input signal and thereby actuates an alarm device. Lines connect the output signal of the rectifier to the monitor input and the first sensing capacitor plate to the collector of one stage of the multivibrator, the second sensing capacitor plate being directly connected to the base of the other stage. The first sensing capacitor plate is at ground potential and the connection to the detector through the line is made by a ground connection at the monitor. (N.W.R.)
- Research Organization:
- Originating Research Org. not identified
- NSA Number:
- NSA-15-018321
- OSTI ID:
- 4016293
- Report Number(s):
- GB 867136
- Country of Publication:
- United Kingdom
- Language:
- English
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