Agilent Technologies ESA Series User's/Programmer's Reference page 63

Selects the ratio between the video and resolution bandwidths. If signal
VBW/RBW
responses near the noise level are visually masked by the noise, the
Auto Man
ratio can be set to less than 1 to lower the noise. The knob and step keys
change the ratio in a 1, 3, 10 sequence. When
Factory
the ratio is set to 1.000 X. The ratio can be changed using the step keys,
knob, or numeric keypad. When
determined by the rules in
Figure 2-3 VBW/RBW Ratio Auto Rules
Key Access:
Chapter 2
and is pressed or
Preset
Figure
BW/Avg
Front-Panel Key Reference
Preset Type
, have been selected,
Auto Couple Auto All
is selected, the ratio is
VBW/RBW (Auto)
2-3.
BW/Avg
is set to
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