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One of the most popular ways to record sound is RF condenser microphone (RF = radio frequency). It is used in telephones and high-fidelity recording microphones. RF condenser microphone can produce very good sound quality. It doesn’t need a big mass to be moved by the soundwave. This means that RF condenser microphone needs a separate power source.
By: Iiro Sivula, Janne Järvinen & Hester Verwej