Dynamic loudspeaker for producing high audio power
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Engraving process and product thereof
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Tapped transformer/switch assembly
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Power control system
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Battery charger
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End of charge detector
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Power control system for periodically and selectively energizing or shorting primary windings of transformers for controlling the output voltage across a common secondary winding
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Engraved plastic article
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Microphone and acoustic equalizer therefor
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Loudspeaker and acoustic transformer therefor
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High output loudspeaker for low frequency reproduction
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High output loudspeaker system
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Constant directivity loudspeaker horn
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Multiple driver manifold
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Microphone with non-symmetrical directivity pattern
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Loudspeaker enclosure for a vibrating diaphragm loudspeaker
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Loudspeaker system with combination crossover and equalizer
