User`s manual

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(spectrum only builds up using specified Number of Averages, can never come
down, thus capturing any strong peaks that might occur).
Marker Block: Used to turn the vertical red marker in the Spectrum Display area on and off
via the Marker button; GREEN LED indicates the marker is on, LED OFF
indicates the marker is off. The marker allows frequency (Freq) and magnitude
(Mag) readout of any point in the spectra. Also, the Show Grid checkbox can
be used to turn the grid markings on and off as needed for viewing the spectral
graph most clearly.
To move the marker, simply click and/or drag the mouse cursor to any desired
point within in the Spectrum Display area. Clicking the Find Peak button
instantly moves the marker to the largest magnitude in the Spectrum Display.
Trace 1 Block: Defines what is displayed by the yellow-colored spectrum trace. The signal
selection combo box allows the user to place the analysis for Trace 1 at any
point in the processing chain; available options depend upon the System
Bandwidth and Input Mode settings.
The Gain scroll bar allows the user to apply digital gain to the Trace 1 input
signal prior to FFT analysis, allowing signals which fall below the 70dB
dynamic range of the analyzer to be viewed. Gain may be adjusted from 0dB
(no gain) to 40dB.
If the Gain setting is too large, the Trace 1 input may be overloaded, causing a
distorted spectrum display. When an overload does occur, the Gain label will
change to OVL and the yellow magnitude readout at the bottom of the display
will change from yellow to red. Overloads affect only the display and have no
effect on the processed signal.
The Show Trace checkbox allows Trace 1 to be turned on and off as
necessary; note that showing both Trace 1 and Trace 2 will tend both to clutter
the grid and slow down the screen update; it is therefore recommended that
only one or the other be checked at any given time, unless overlayed viewing is
needed.
Trace 2 Block: Identical to the Trace 1 Block, except that it manages the blue-colored
spectrum trace.
Spectrum Display: Spectra are displayed in Cartesian (X,Y) format, with the Y axis representing
magnitude in dB and the X axis representing frequency in Hertz. An optional
grid can be superimposed on the black background to assist the user in visually
judging frequency and magnitude of spectral components.