Contents - Index - Next


What is a Spectrum Analyzer

A spectrum analyzer is an instrument used to convert a signal from the time domain (amplitude-vs-time) to the frequency domain  (amplitude-vs-frequency).  If you are familiar with an ordinary oscilloscope you know what a time domain display looks like.  A frequency domain display is known as a spectrum.   Unless you are measuring a single tone, an oscilloscope provides little in the way of frequency information; however, a spectrum analyzer clearly reveals this information.  

What Can it Do?
A Spectrum Analyzer is very useful for measuring the fundamental frequency  components which are contained in a signal.  It can accurately measure the frequency of single or multiple tones and the frequency difference between them. 

How does it work?
The program works in conjunction with a DT 9800 data acquisition module.  SpectraPLUS -DT then performs an "Analog-to-Digital" conversion on the analog signal.  This digitized signal is then passed through a math algorithm known as a Fast Fourier Transform (FFT) which converts the signal from the time domain to the frequency domain.  The CPU on your computer is used to perform this transformation. 


See also:  Performance Issues