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Spectrum Analyzer Mode
R&S
®
Cable Rider ZPH
192
User Manual 1321.0950.02 ─ 07
Figure 8-7: Screen layout for the AM modulation depth measurement
1 = AM modulation depth measurement mode
2 =
Measurement Result View
3 = Modulation depth
4 =
Parameter view
5 =
Configuration overview
6 = Threshold line (blue line)
7 = Trace
8 = Markers
9 = AM modulation depth softkey menu
By default, delta marker 2 is active for editing. If you move the delta marker to another
position, the other delta marker will be moved by the same distance relative to the nor-
mal marker. Note that this happens only if you move delta marker 2 (D2). When mov-
ing delta marker 3 (D3), only this marker is repositioned.
From the values of the markers, the R&S Cable Rider ZPH then calculates the AM
modulation depth. The AM modulation depth is the ratio between the power values at
the reference marker and at the delta markers. When the powers of the two AM side
bands are not the same, the R&S Cable Rider ZPH uses the mean value of the two
sideband values.
If the R&S Cable Rider ZPH is unable to find any AM modulated carriers, it shows the
message:
Performing Spectrum Measurements