Rohde & Schwarz FSH4, Руководство по эксплуатации

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R&S FSH Spectrum Analyzer Mode
Performing Spectrum Measurements
Operating Manual 1309.6275.12 - 14 60
M Activate the input by pressing the "Select" softkey.
The channel turns green and the check box in the first column is marked.
M Enter the limit value you need.
The R&S FSH automatically activates the check flag, so that the limit is included in
future limit checks.
M To deactivate the limit check for a specific channel, move the cursor to the channel
in question with the rotary knob or the cursor keys and deselect it with the "Select"
softkey.
Defining absolute limits
M Press the "Channel Settings" softkey.
M Select the "Channel Limit Absolute" menu item.
The R&S FSH opens a dialog box to define the absolute limits for each adjacent
channel.
M The procedure of defining absolute limits is analogous to that of defining relative
limits.
Performing a limit check
M Press the "Channel Settings" softkey.
M Select the "Check Channel Limits" menu item.
The R&S FSH automatically
performs limit checks.
The results of the limit check are displayed in the table above the trace. If a result
fails the limit check, it turns red and has a star (*) in front of its power level.
2.1.5 Measuring the Spectrum Emission Mask
The Spectrum Emission Mask (SEM) measurement is a method to detect spurious
emissions or intermodulation products of a signal. When performing a SEM
measurement, the R&S FSH checks the signal against a spectral mask to see whether
the signal complies with a specific standard or not. Therefore, the R&S FSH provides
predefined spectrum emission masks for various telecomunications standards.
However, you can define your own spectral masks with the R&S FSH4View software to
perform measurements in frequency ranges other than the predefined. To learn how to
define Spectrum Emission Masks, refer to the R&S FSH4View manual.
M Press the MEAS key.
M Press the "Meas Mode" softkey.
The R&S FSH opens the measurement menu.
M Select the "Spectrum Emission Mask" menu item.
The R&S FSH starts to measure the spectrum emission mask.