HW V4 / © 2005 – 2013 Aaronia AG, DE-54597 Strickscheid
21
Manual Spectran V4
Functional description
5.3.4. RBW
(bandwidth)
RBW
(3MHz)
RBW
(1MHz)
By adjusting bandwidth, you can adjust detail clarity and
sensitivity at once.
When bandwidth is set to a very high value or even to FULL,
the sweep will be very fast, however, the display becomes
comparatively inaccurate and sensitivity is low. Hence, very
weak signals will not be picked up anymore. The smaller the
bandwidth, the longer the sweep will take, but the display
will be more precise and weaker signals can still be
displayed. Thus, for example, a single signal initially
sweeped with high bandwidth can turn out to be a number of
several narrow, close together signals.
However, this gain in accuracy has its downside in the far
longer sweep times.
5.3.5. VBW
(video filter)
VBW
= Full
VBW
– 100KHz
The video filter is intended for visual smoothing of the signal.
The lower the video filter setting, the broader and smoother
the display of the signal becomes. Using this filter, you can
mostly suppress unwanted noise, harmonics or sporadic
peaks. However, with a very low video filter setting, the
display can become less meaningful. In our example, there
might be three separate signals present. However, the low
video filter straightens these signals out to become one
single “smooth” signal. The alleged noise band around the
signal has also been “smoothed out”. Thus, when dealing
with weak signals, the highest possible video filter setting
should be used.
Tip
: By using the Right/Left arrow keys, you can simply move the sweep range by exactly
one Span to the right or left.
