The latch works by running an electrical current down a signal wire, through two switches.

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The maneuver also required distributing fifty-seven tons of new maps, uprooting and reinstalling an extensive signal-wire network, and stockpiling fuel and ammunition, including shells for twelve hundred guns in the army's 108 artillery battalions.

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If you crack open your GPS, you could extend the wire between the antenna and the internal antenna, but the loss from the extra wire would degrade the signal.

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The fences work by burying a boundary wire which transmits a radio signal to a collar.

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It's also providing copper cable networks for the "last mile" of installed wire from central switches to homes and businesses, and products that help increase bandwidth, maintain signal integrity and optimize wavelength.

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He can sense when a moth is blowing a raspberry by attaching a wire to the muscle that controls the insect's tongue, and using it to transmit a signal via one of Dr Hildebrand's tiny electronic backpacks.

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