Resolution Bandwidth; Video Bandwidth - Keysight N9912A User Manual

 Then
Resolution Bandwidth (Res BW)
In SA Mode, the Res BW provides the ability to resolve, or see closely spaced signals.
The narrower (lower) the Res BW, the better the spectrum analyzer can resolve
signals. In addition, as the Res BW is narrowed, less noise is measured by the
spectrum analyzer ADC and the noise floor on the display lowers as a result. This
allows low level signals to be seen and measured. However, as the Res BW is
narrowed, the sweep speed becomes slower.
How to set Res BW
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The current Res BW setting is shown at the bottom of the screen.
#Res BW x.xx XHz ( # ) means manual setting.
This setting could impact the accuracy of the measurement. See Specifications on
page 201.
NOTE The Res BW setting also affects the Sweep Type setting. Learn how on page 82
Video Bandwidth (Video BW)
Video BW is a smoothing operation that is performed after measurement data is
acquired. The trace data is effectively smoothed so that the average power level of
the displayed noise is the same, but the peaks and valleys of adjacent data points are
smoothed together. More smoothing occurs as the Video BW is set lower. However,
as the Video BW is narrowed, the sweep speed becomes slower.
How to set VBW
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 Then
NOTE To change this setting from Man to Auto, press Video BW twice.
The current Video BW setting is shown at the bottom of the screen.
# VBW x.xx XHz ( # ) means manual setting.
When the Res BW/Video BW ratio exceeds 10,000, a
appear to indicate that the Video BW filter has reached the maximum capacity for
averaging.
In Zero Span, the maximum Res BW/ Video BW ratio is 100.
SA (Spectrum Analyzer) Mode
Battery Saver OFF
Press BW 2.
Res BW Auto | Man.
Res BW is coupled to the frequency span. As the frequency span is
Auto
o
narrowed, the Res BW is also narrowed providing increased ability to resolve
signals.
To change this setting from Man to Auto, press Res BW twice.
Enter a Res BW value using the numeric keypad, the ▲|▼ arrows, or the
Man
o
rotary knob. Then press a multiplier if necessary or press Enter.
Press BW 2.
Video BW Auto Man.
Couples Video BW to the ResBW in a 1-to-1 ratio.
Auto
o
Enter a Video BW value using the numeric keypad, the ▲|▼ arrows, or
Man
o
the rotary knob. Then press a multiplier if necessary or press Enter.
warning may
Meas UNCAL
81