See frequency modulation.
In physics, symbol for frequency modulation, or the variation of the frequency of a carrier wave in accordance with the signal to be transmitted. Used in radio, FM is constant in amplitude and has much better signal-to-noise ratio than AM (amplitude modulation). It was invented by US electronic engineer Edwin Armstrong.
Factory Mutual Research Corporation. An organization which sets industrial safety standards.

Fermium

Federated States of Micronesia

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