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ognized, while the ear and brain try to supplement the missing periodicity. The
impulse generates bars in the entire frequency range which die down in ampli-
tude as the frequency increases. This means that all those frequencies have
been found by the Fourier transformation, although the impulse was an isolat-
ed occurrence with not really any frequency. The human ear will respond simi-
larly because its design will cause an excitation of all hair cells along the wind-
ings of the cochlear and send signals of all audible frequencies to the brain.
16.3 Typical Gear Noise
In a constructed example, the single flank error signal in the graphic in Fig-
ure 2 consists only of sine functions. The top graphic is the recording of one
ring gear revolution. In the example a ratio of 3.00 was chosen, which means
the graphs in Figure 2 will be exactly repeated for additional ring gear revolu-
tions.
Figure 2: Separation of harmonic transmission elements of motion graph
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