The Spectrum Application
R&S
®
FPC
87
User Manual 1178.4130.02 ─ 07
● Two arrows (one up, one down) indicate that the spectrogram area displayed is
somewhere in the middle of the available history.
● A single up arrow in the upper right corner of the spectrogram indicates that the
lowest line of the spectrogram represents the end of the history buffer.
14.2.7.2
Color Definition
Colors are an important element of the spectrogram. The R&S
FPC provides various
features to customize the display for the best viewing results.
Selecting a color scheme
The first and most obvious way to adjust colors is to select a different color scheme.
1. Press the "Meas" key to open the measurement menu.
2. Select the "Settings" menu item to open the spectrogram settings menu.
3. Select the "Color Table" menu item to open the color table menu.
4. Select the color scheme you are most comfortable with.
The R&S
FPC adjusts the screen colors according to your selection.
The following color schemes are available.
● Default
● Green-Yellow
● Green-Blue
● Black-White
● Red-Purple
● Blue-Black
Adjusting the color distribution
It is possible that the color distribution is not ideal in the default configuration. The
R&S
FPC provides several settings to further enhance the color display in the spectro-
gram.
The following examples are based on the red-purple color scheme.
The first method is to cut the reference level. It eliminates amplitudes from the color
map that are not part of the signal.
Example: By default, the spectrogram reference level is -20
dBm.
That means that signal parts with an amplitude of -20
dBm would be red in the spectro-
gram, and signal parts with a very small amplitude would be purple. Everything in
between is a shade of the colors between. As the colors are distributed over a very
large range (about a 100
dBm or more), it is likely that you cannot distinguish details in
the signal.
Measurements and Result Displays
