User manual

Chapter 2 Front Panel Operation RIGOL
User’s Guide for DSA700 Series
2-21
Sweep and Function Settings
BW/Det
Set the RBW (Resolution Bandwidth), VBW (Video Bandwidth) and detector type
parameters of the analyzer.
RBW
Set the desired resolution bandwidth in order to distinguish between signals which
are close in frequency.
Key Points:
 Reducing RBW will increase the frequency resolution, but will increase the
sweep time (Sweep Time is affected by a combination of RBW and VBW when
it is in Auto mode).
 RBW varies with the span (non-zero span) in Auto RBW mode.
 You can modify this parameter using the numeric keys, knob or direction keys.
For more details, please refer to "Parameter Setting".
Note: If the detector type is "Quasi-Peak" or the filter type is "EMI", RBW can be
200 Hz, 9 kHz or 120 kHz only.
VBW
Set the desired video bandwidth in order to filter out the noise outside the video
band.
Key Points:
 Reducing the VBW will smooth the spectrum line to differentiate small signals
from noise, but will increase the sweep time (Sweep Time is affected by a
combination of RBW and VBW when it is in Auto mode).