Tektronix NetTek YBT250, Руководство пользователя

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Locating Interference
3- 44
YBT250 Field Transmitter & Interference Tester User Manual
4. Select a channel.
5. Tap the Reverse Link button.
6. Tap the Interference button.
7. Tap the Noise tab.
The Noise Floor measurement is displayed below the trace
display. Noise Floor is displayed in dBm, with a resolution of
0.1 dB. The two vertical lines in the trace display indicate the
upper and lower frequencies of the channel being measured.
Locating Intermittent Interference
Requires Option IN1
Intermittent interference can be difficult to identify. The YBT250
Spectrogram display is ideal for spotting intermittent interference. A
spectrogram displays how a signal changes over time, in addition to
frequency and level. Because the spectrogram displays signals over a
period of time, signals that are intermittent are easy to spot.
To locate an intermittent interference signal:
1. Connect the YBT250 RF INPUT to the signal. The signal may be
from an antenna for off-the-air signals or you may need to
connect to a test point on the base station.
2. Tap the Spectrum button .
3. Set the Measurement Frequency and span to show the frequency
range of concern.
4.
Set the Vertical Scale (dB/div) so that the trace nearly fills the
vertical range of the graph area.
5. Tap the Spectrogram tab. See Figure 3--25.