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R&S FSH
Spectrum Analyzer Mode
Performing Spectrum Measurements
Operating Manual 1309.6275.12 - 14
65
2.1.6.2 Optimizing the Display of Harmonics
The R&S FSH places the markers on the other harmonics even if they are outside of
the display range.
M
Press the MEAS key.
M
Press the "Adjust Settings" softkey.
The R&S FSH performs a measurement to determine the ideal reference level,
frequency and span in order to display all harmonics.
2.1.6.3 Activating the Harmonics List
To see the exact frequency of the harmonic, you can activate the marker list that
shows the value for each harmonic or marker.
M
Press the MKR key.
M
Press the "View List" softkey.
The R&S FSH displays the marker list that contains the values for each harmonic.
2.1.7 Measuring the AM Modulation Depth
The AM Modulation Depth measurement analyzes AM modulated signals and
calculates the modulation depth of the signal using the measurement results. Note that
the measurement works properly only if you apply an AM modulated signal.
M
Press the MEAS key.
M
Press the "Meas Mode" softkey.
The R&S FSH opens the measurement menu.
M
Select the "AM Modulation Depth" menu item.
The R&S FSH starts to measure the AM modulation depth.
After you have started the measurement, the R&S FSH places three markers on the
trace. The first marker is placed on the peak power level. The R&S FSH assumes that
position as the level of the carrier. The second and third markers are delta markers.
These are placed symmetrically on the adjacent peak values to the left and right of the
carrier.
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
normal marker. Note that this happens only if you move delta marker 2 (D2). When
moving delta marker 3 (D3), only this marker is repositioned.
From the values of the markers, the R&S FSH 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 FSH uses the mean value of the two sideband values.