User`s guide

Key Reference 4
N9320A Spectrum Analyzer 75
BW/Avg
Activates the resolution bandwidth function and accesses the
softkeys that control the bandwidth functions and averaging.
Res BW
Auto Man
Changes the 3 dB resolution bandwidth of the analyzer from
10 Hz to 3 MHz using the knob or arrow keys. When under
1 kHz, the available bandwidth is 10, 30, 100 Hz or 300 Hz.
If you enter an invalid bandwidth using the numeric keypad,
the analyzer uses the closest available bandwidth. As the
resolution bandwidth is decreased, the sweep time is
modified to maintain amplitude calibration. Resolution
bandwidth is also related to span. As span decreases, the
resolution bandwidth decreases. As the resolution bandwidth
changes, the video bandwidth, if VBW/RBW is set to AUTO,
changes to maintain the VBW/RBW ratio.
A “#” mark appears next to “Res BW” on the display when it
is not coupled. To recouple the resolution bandwidth, press
Res BW (Auto).
Key access:
Video BW
Auto Man
Changes the analyzer post- detection filter from 1 Hz to 3
MHz using the knob or arrow keys. If you enter an invalid
bandwidth, the analyzer use the closest available bandwidth.
As the video bandwidth decreases, the sweep time increases
to maintain amplitude calibration.
A “#” mark appears next to “VBW” on the bottom of the
analyzer display when it is not coupled. To couple the video
bandwidth, press Video BW (Auto).
Key access:
VBW/RBW
Auto Man
Sets the ratio between the video and resolution bandwidths.
If a signal level close to noise level is visually masked by the
noise, you need to set the ratio to less than 1 to lower the
noise. When Preset Type is set to Factory and Preset is pressed,
the ratio is set to 1. Change the ratio by using the arrow
keys, knob, or numeric keypad. When VBW/RBW (Auto) is
selected, the ratio is determined automatically by the rules
in Figure 1.
BW/
Avg
BW/
Avg