Agilent Technologies 89410A Operator's Manual page 85

5.
Change the number of colors used in the color map.
Press [return].
Press [
Press 5 [enter].
Press 10 [enter].
Press 64 [enter] to return to the default number of colors.
In this example, changing the number of colors erases the upper portion
of the spectrogram display. This happens because the traces in this area
are not in the spectrogram buffer. In other words, the spectrogram buffer
does not contain enough traces to fill the entire display. Changing the
number of colors forces the analyzer to recompute scaling factors for the
y-axis. The analyzer can do this only for traces in the spectrogram buffer.
6.
Adjust the threshold to remove noise from the spectrogram display.
Press [threshold].
Rotate the knob to obtain the desired display.
As demonstrated, you can use the threshold feature to hide unwanted
information. When you specify a threshold, the analyzer displays colors at
or above the threshold; below the threshold, the analyzer uses the bottom
color in the colorbar.
You specify threshold as a percentage of the colorbar. A threshold of 0%
displays the entire signal. A threshold of 50% only displays colors in the
upper half of the colorbar—colors below this point (or threshold) are
displayed in the same color as the bottom color in the colorbar.
Hint
You may overlay another type of trace on a spectrogram and observe, for
example, the spectrum or PSD of the input signal. To do this, press [Display]
[view/overlay traces] and turn on the trace that you want to use as an overlay.
Color map, enhance, and threshold affect all traces that contain
spectrogram displays.
displays, changing the color map for trace A also affects trace B.
] 2 [enter].
number colors
For example, if traces A and B contain spectrogram
Using Waterfall and Spectrogram Displays (Opt. AYB)
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