Specifications

79
Let’s see what happened to our dynamic range as a result of our concern
with measurement error. As Figure 6-6 shows, second-order-distortion
dynamic range changes from 72.5 to 61 dB, a change of 11.5 dB. This is one
half the total offsets for the two curves (18 dB for distortion; 5 dB for noise).
Third-order distortion changes from 81.7 dB to about 72.7 dB for a change
of about 9 dB. In this case, the change is one third of the 18 dB offset for the
distortion curve plus two thirds of the 5 dB offset for the noise curve.
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01 3 4 5 6 7 82
Displayed S/N (dB)
Error in displayed signal level (dB)
Figure 6-7. Error in displayed signal amplitude due to noise