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11.3 Selecting measurement parameters
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11.3 Selecting measurement parameters
Measurement parameters are basically set in the same way as for
Time Domain (Scope) High Resolution Scope mode (see
Selecting
measurement parameters
on page 184). The following settings are crucial
here:
1.
Press the
Fcent
softkey to set the center frequency (see
Setting the
center frequency (Fcent)
on page 91).
2.
Press the
BW
softkey to set the channel bandwidth (see
Setting the
bandwidth (RBW / CBW)
on page 94).
3. Time Span
is always automatically set to the maximum possible value
when the bandwidth is changed. Redfuce the value if necessary (see
Selecting Time Span
on page 205).
4.
Press the
Reference Level
softkey to set the reference level for correct
modulation (see
Setting the reference level (Reference Level)
on page 97).
5.
Make settings in the Trigger menu in order to start event controlled
capture. Otherwise the measurement will be in Free Run mode (see
Using the trigger function
on page 192).
11.3.1 Setting the channel bandwidth (CBW)
You must choose a channel bandwidth that allows the entire signal to be
captured. The maximum possible time resolution (1/CBW) results from the
bandwidth setting.
The fast Fourier transformation (FFT) requires the selection of a higher
channel bandwidth for computing the spectrum.
Fspan = 0.8 x CBW (maximum value approx. 22 MHz)
 See
Setting the bandwidth (RBW / CBW)
on page 94.
11.3.2 Selecting Time Span
1.
Press the
Time Span
softkey.

Entry is in seconds by default.