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Results tagged with microwave
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user 97482
Microwaves are radio waves with a frequency from 300MHz to 300GHz which corresponds to a wavelength of one meter down to one millimeter. Often in RF engineering however it is used to refer to a narrower region such as 1 to 100GHz.
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votes
A few questions on PIRs and other motion detectors
PIR sensors have quite a few advantages:
they’re very cheap
they use very little power (since they’re passive) – very important for battery powered/wireless sensors. We’re talking microwatts here.
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