The Spectrum Application
R&S
®
FPC
92
User Manual 1178.4130.02 ─ 07
2. Select the "Time Line <x>" menu item.
The R&S
FPC opens an input field to define the position of the corresponding time
line (T1 or T2).
3. Position the time line by entering a number or moving it with the rotary knob.
Entering 0 sets the time line marker on the most recent frame. The maximum value
that you can enter is 1024 (the maximum number of frames the R&S
FPC can
store in its memory).
Figure 14-5: Time lines in the spectrogram
Note that not all frames are visible on the screen. If a frame is part of the history
outside the visible area, the time line is also not visible and you have to scroll
through the spectrogram to be able to see it again.
The upper window displays the spectrum of the frame at the time line position. By
moving the time line, you can thus browse through the history of spectra stored in
memory.
In the marker information field, the R&S
FPC shows the time stamp of the time line.
The time stamp of the first time line T1 is always referred to the top-most frame. A
time stamp of 00:00:50:000, for example, means that the data was measured
50
seconds prior to the topmost frame).
In addition to the time line (horizontal marker), you can also use (vertical) markers
in the spectrogram.
With the help of the
and the time line, you are able to find the exact
moment when a specific event has occurred in the spectrum.
4. Press the "Marker" key.
The R&S
FPC activates a marker and sets it on the peak level of the currently dis-
played spectrum.
5. Use the rotary knob or the cursor keys to move the marker on the x-axis to the fre-
quency you want to analyze, or enter the frequency directly with the number keys.
6. Select the "Time Line" softkey and browse through the spectrums using the rotary
knob or the cursor keys until the spectrum of interest is displayed in the upper win-
dow.
The time stamp of the selected time line (displayed in a field above the diagram
area) gives you a precise indication on when the event shown in the spectrum
occurred.
Measurements and Result Displays
