How To Use A Spectrum Analyzer (video)

Spectrum Analyzers measure the magnitude of input signals at each frequency within the range of the instrument, showing the power spectrum of signals. By analyzing the spectra of electrical signals, peak frequency, power, distortion, harmonics, bandwidth, and other spectral components of a signal can be observed that are not easily seen in time domain waveform displays. These parameters are useful in the characterization of electronic devices, such as wireless transmitters.

here's a helpful video by Jason Chonko from Siglent Technologies:  

https://youtu.be/lD01VYo9TSY