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JD700B Series User’s Guide
Figure 394 RFoOBSAI spectrum measurement
Conducting spectrogram
The Spectrogram is particularly useful when attempting to identify periodic or intermittent signals as it
captures spectrum activity over time and uses various colors to differentiate spectrum power levels. When
the directional antenna is used to receive the signal, you will see a change in the amplitude of the tracked
signal as you change the direction of the antenna and see a change in the Spectrogram colors. The source
of the signal is located in the direction that results in the highest signal strength.
After setting test parameters as described in “Configuring test parameters” on page 653, you can perform
spectrogram measurements.
Procedure
1
Press the
MEASURE SETUP
hot key.
2
To set the amount of time between each trace measurement:
Press the
Time Interval
soft key.
Enter a value, and then press the
Sec
soft key.
3
To set the time cursor on a specific trace position, complete the following steps:
Toggle the
Time Cursor
soft key and select
On
.
Press the
Position
soft key.
Turn the rotary knob to move the time cursor. You can also enter a value and then press the
Enter
soft key.
To turn the time cursor off, toggle the
Time Cursor
soft key and select
Off
.
NOTE
Enabling the time cursor puts the measurement on hold and you can make post-
processing analysis for each measurement over time using the time cursor.
4
To start a new measurement, press the
Reset/Restart
soft key.
5
To clear current (C) and history (H) status of OBSAI alarm on LOS and LOF and start a new
monitoring, press the
MEASURE SETUP
hot key and then the
Clear History
soft key.
6
Optional
. Go to
SAVE/LOAD > Save
, and then select the save option from the choices available
for your measurement mode. See “Using save” on page 35 for more information.
The spectrogram shows a vertical line on the chart when the marker is enabled on the screen.
