beatfrekvensoscillator
Beatfrekvensoscillator, often referred to in English as beat frequency oscillator (BFO), is a local oscillator used in some radio receivers to generate an audible reference signal for demodulating certain modulation modes. The oscillator operates at or near the receiver’s intermediate frequency and is mixed with the IF signal in the detector, producing an audio-frequency beat that can be heard as sound.
In practice, the BFO is used to recover information from signals that lack conventional amplitude modulation,
Technically, BFOs are typically simple LC oscillators built with transistors or tubes and paired with the receiver’s
A related use of the term exists in metal detectors, where a beat frequency oscillator compares two