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Personnel monitoring tag with tamper detection and secure reset
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Drive-by personnel monitoring system with radio link
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Automatic personnel monitoring system
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Methods and apparatus employing apparent resonant properties of thin conducting materials
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Electronic coin detection apparatus
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Gaming apparatus
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Gaming apparatus
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Techniques for detecting a condition of termination on a telephone line
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Gaming apparatus with color sensitive detector
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Gaming device using visible randomization
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Techniques for detecting a condition of response on a telephone line
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Telephone sequential number dialer with number incrementing
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Telephone polling apparatus using a plurality of timers to detect the line conditions
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Telephone polling apparatus
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