Elenco PK101 w/ Computer Interface - Manual (Page 14)

Smooth, well-rounded, and repetitive waveforms (in oscilloscope mode) have nearly all of their ener-
gy at a specific frequency. “Square” or “rectangular” looking waveforms and most music have a
series of mathematically-related peaks, while “random” waveforms (like from blowing into the speak-
er or several people talking at the same time) have a frequency “blob” instead of distinct peaks.
Click on the FFT button to look at the frequency spectrum for these signals. Try the amplitude and time
scales shown here to start, but your best settings will depend on what sounds you make, how loud you
speak, and how close you are to the speaker.
Notice that most women have
higher-frequency voices than most
men, and so their frequency peaks
are further to the right on your dis-
play.
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