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US2249534A
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Static reducing device
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Method of and means for reducing electrical disturbances
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Method of and means for reducing electrical disturbances
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Method of and means for reducing the effects of undesired oscillations
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Method of and means for reducing electrical disturbances
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Method and means for reducing electrical disturbances
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Method of and means for reducing the effects of electrical disturbances
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Method of and apparatus for controlling alternating currents
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Method of and apparatus for controlling alternating current
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Signaling system
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Method of and apparatus for electrical communication
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Microphone
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Apparatus for the production of high-frequency currents of electricity.
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Apparatus for and method of producing high-frequency currents of electricity.
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Apparatus for the production of high-potential electric currents.
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Signalling system
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Method of and apparatus for electrical communication
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