Sound is pressure — the louder the sound, the greater the pressure. The greater the pressure, the more damage it can do to your ears. If you’re in a noisy environment, it’s important to know how ...

This circuit can easily be assembled on a small piece of prototyping board. Use low-current types for the LEDs. They have a low forward voltage and are fairly bright at current levels as low as 1 mA.

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It’s music to their ears. City regulators are making a bid to address the bane of New Yorkers’ existence: noise! The city Department of Environmental Protection ...

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