Rohde & Schwarz R&S UPP, Руководство пользователя

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Getting Started
R&S
®
UPP
105 User Manual 1411.1055.32 ─ 10
a) In the default instrument setup, the numeric measurement display is already
open.
If the DUT is correctly connected to the audio analyzer, the measured values
for the total harmonic distortion can be read off in the first column.
In the default setup, THD+N values are given in dB; if a display in % is desired,
this unit can be changed in the "Function Config" panel.
5. Step: Displaying the spectrum in the graphical window
Display of the numeric value alone is sufficient for the majority of harmonic distor-
tion measurements. Here, however, the spectral composition of the output signal at
the DUT is also to be analyzed.
With the audio analyzer, it is possible to follow up all distortion measurements with
an FFT analysis.
The necessary settings for this are explained in the following section:
a) In the "Analyzer Function" panel already used for configuring the THD+N mea-
surement, an FFT analysis to be performed following the measurement can be
set after the actual measurement function has been selected.
To do this, activate the "Post
FFT" checkbox.
The size of the FFT can be adjusted if necessary.
b) To graphically display the results of the FFT analysis, first change to screen 5,
which is empty in the default setting.
Introduction to Instrument Operation Using Examples