It is designed to detect the low-frequency radio pulses emitted by lightning strikes.

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They emitted so much radio-frequency interference that Mr. Clark struggled to get a clear signal for the band's wireless instruments and in-ear monitors.

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Agarwal is in the early stages of further research that can model the human body's role in protecting from radio-frequency electromagnetic waves emitted from cell phones.

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The trick is to tune the crystal, by modifying the details of pattern, so that as much of the emitted energy as possible is at the frequency most efficiently captured by indium gallium arsenide.

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Extrapolating from Dr Freund's laboratory experiments, the strain in a real-life geological fault such as the San Andreas could, as it shifted, generate hundreds of thousands of amperes per cubic kilometre in a fluctuating pattern that would cause very low frequency radio waves to be emitted, thus disrupting the ionosphere.

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