Technical data

94 Agilent N8201A Performance Downconverter Synthetic Instrument Module, 250 kHz to 26.5 GHz
4 BW/Avg
Video BW
Enables you to change the N8201A post-detection filter from 1 Hz to 8 MHz in
approximately 10% steps. In addition, a wide-open video filter bandwidth (VBW) may be
chosen by selecting 50 MHz. Video BW (Auto) selects automatic coupling of the Video BW
filter to the resolution bandwidth filter using the VBW/RBW ratio set by the VBW/RBW
key.
Sweep Time is coupled to Video Bandwidth (VBW). As the VBW is changed, the sweep
time (when set to Auto) is changed to maintain amplitude calibration. This occurs because
of common hardware between the two circuits, even though the Video BW filter is not
actually “in-circuit” when the detector is set to Average. Because the purpose of the
average detector and the VBW filter are the same, either can be used to reduce the variance
of the result.
Although the VBW filter is not “in-circuit” when using the average detector, the Video BW
key can have an effect on (Auto) sweep time, and is not disabled. In this case, reducing the
VBW setting increases the sweep time, which increases the averaging time, producing a
lower-variance trace.
However, when the EMI Average detector is selected, the Video BW is restricted to 1 Hz
while the sweep time is set to Auto.
When using the average detector with either Sweep Time set to Man, or in zero span, the
Video BW setting has no effect and is disabled (grayed out).
A “#” mark appears next to VBW on the bottom of the N8201A display when it is not
coupled. To couple the video bandwidth, press Video BW (Auto).
Key Path: BW/Avg
Saved State: Saved in Instrument State
Factory Preset: Auto (3 MHz)
Range: 1 Hz to 50 MHz
Remote Command:
[:SENSe]:BANDwidth|BWIDth:VIDeo <freq>
[:SENSe]:BANDwidth|BWIDth:VIDeo?
[:SENSe]:BANDwidth|BWIDth:VIDeo:AUTO OFF|ON|0|1
[:SENSe]:BANDwidth|BWIDth:VIDeo:AUTO?
Example:
BAND:VID 1 kHz