A spectrum analyzer or spectral analyzer is a device, which is used to calculate the magnitude of an input signal within the full frequency range. The main purpose of the spectrum analyzer is to measure the power of spectrum of “known” and “unknown” signals. The Electrical signal is used as input signal in a spectrum analyzer for measurements. However, it can measure other signals such as acoustic pressure waves or optical light waves converted to their electrical signal using transducers.
The spectrum analyzer displays the frequency on the horizontal axis and amplitude on the vertical axis. A spectrum analyzer might look like an oscilloscope to a casual observer. But in reality it is different except for those laboratory instruments which can operate as oscilloscope or a spectrum analyzer.
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