Page 31 - Vibrations
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When we use a dB scale.
By using the dB scale more prominence is given to
the smaller features - in this case the noise.
As can be seen from this example the noise is 30dB
down on the signal peak (close to 0 dB).
To measure the signal to noise ratio (S/A), perform
several spectra, average them and measure the
noise magnitude.
Perform the ratio calculation.
When measuring vibrations, these are the methods
used to try an characterise them.
Very often when measuring vibrations, small
components are masked by much larger ones.
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