Keysight Technologies FieldFox A Series, User Manual

Page: 166 / 756

166 Keysight N9927-90001 User’s Guide
SA (Spectrum Analyzer) Mode
SA Mode Settings
This setting could impact the accuracy of the measurement. See Specifications
in Appendix B.
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
— Press BW 2 .
— Then Video BW
— Then choose from the following:
— Auto Couples Video BW to the ResBW in a 1-to-1 ratio.
— Man Enter a Video BW value using the numeric keypad, the
arrows, or the rotary knob. Then press a multiplier if necessary or
press Enter . Setting VBW higher than RBW may smooth the trace.
.
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 Meas UNCAL warning
may appear to indicate that the Video BW filter has reached the maximum
capacity for averaging.
Sweep Type
In SA mode, the FieldFox uses two sweep types to process inputs signals. The
sweep type that is currently being used ( FFT or Step ) is displayed in the
lower-left corner of the FieldFox screen.
For a more comprehensive tutorial, see Spectrum Analysis Basics (App Note
150) at http://literature.cdn.keysight.com/litweb/pdf/5952-0292.pdf
The Res BW setting also affects the Sweep Type setting. Learn how in
“Sweep Type” on page 166
To change this setting from Man to Auto, press Video BW twice.