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R&S ZVH
Spectrum Analyzer Mode (R&S ZVH-K1)
Performing Spectrum Measurements
Operating Manual 1309.6946.12 - 09
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The result however, still does not
show signal differences in detail.
The only thing that happened is
that the colors have shifted, in the
example to yellow, because the
color that corresponds to the
reference level has shifted from
green to yellow. All other colors
that are part of the color scheme
are still unused, because the
spectrogram level range is still the
same (150 dB).
► Press the "Spectrogram Settings" softkey.
► Select the "Spectrogram Level Range" menu item.
The R&S ZVH opens an input field to enter the spectrogram level range.
In the example, the level range of the signal is from about -60 dBm to about
-100 dBm.
► Therefore set the level range to
40 dB to get the whole signal.
As the level range is now adjusted,
the R&S ZVH is able to map its
complete color range to the level
range of the signal.
This means that signal parts with a
low amplitude are in a shade of
green while signal parts with a
high amplitude are yellow.
The best way to display a spectrogram is therefore to reduce the level range until
the lowest signal part is mapped to the lower end of the color map and the highest
signal part to the upper end of the color map.
In a last step you can configure the spectrogram in a way that it only shows signal
peaks in color and the noise floor in black. To get a result like that you have to
reduce the level range, until the noise floor is outside the displayed range.