Page 8 - Vibrations 4
P. 8
You will note the positive waveform is larger than the
negative waveform – distortion is taking place.
As Fourier said, whenever you distort a sine wave, you will
be adding harmonics to it.
2
2
2
√ + + + ⋯
3
2
1
=
1
For a good audio system, you would expect the THD to be
no more than 0.5%.
The response of an accelerometer is being checked in this
example.
You can see the region in the accelerometer which is
linear – the region over which is should be used.
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