QuantAsylum QA401 User
’s
Manual
Page
37
In the plot above, we can see the second harmonic is about -107 dB below the fundamental. If we use
markers, we can see this a bit easier below. The THD function will sum the harmonic powers all the way
up to the specified Measurement Stop. In the plot above, the sum of the harmonic power is -107.1 dB.
To go from a dB measurement to a percent measurement, use the following:
THD pct = 10^(THDdb/20) * 100
This is done automatically in computing the % distortion figure.
