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Collapsible multicorner reflector for ultra high frequency radiant energy
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Measuring potential gradients in space
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Humidity variable resistance
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Advertising method and magnet motivated object
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Altitude measuring
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Pulse echo distance and direction finding
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Humidity measuring
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Measuring cloud height and thickness
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Warning system for indicating the proximity of aircraft
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Automatic steering system
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Radio system for automatic control of aircraft, as during landing
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Aircraft blind landing beam system
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Ultrahigh frequency radio amplifier
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Multistage ultra high radio frequency amplifier
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Visual type radio beacon
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Radio system for azimuth indication
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Radio system for collision prevention
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Method and apparatus for radio beacon course and quadrant identification
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Course indicator for blind flying and landing
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Radio beam and receiving device for blind landing of aircraft
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