Tektronix NetTek YBT250, Руководство пользователя

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Locating Interference
YBT250 Field Transmitter & Interference Tester User Manual
3- 41
You can change the volume of the audible tone using the slider
control at the bottom-left of the results display area.
The Beep causes the audible tone to switch on and off at a rate that
varies with the signal strength. The stronger the signal, the faster the
audible tone beeps. The Beep is activated by selecting the
Beep
checkbox located at the bottom-center of the results display area.
You can increase the rate at which the signal strength indicators are
updated by selecting the
Fast Update checkbox. When Fast Update
is checked, the trace update rate is slowed so that the strength
measurement can speed up. The variation in pitch of the audible tone
(and Beep if it is selected) occurs much faster when Fast Update is
enabled.
Demodulating an Interfering Signal
Requires Option IN1
One method to identify an interfering signal is to demodulate the
signal. This enables you to listen for any identifying information,
such as a station ID, in the signal. A station ID can be particularly
helpful when the interfering signal is a radio or broadcast television
station. You may also be able to discriminate between possible
sources by listening to the characteristic sounds of paging, video,
control signals or the harmonics of other common signals.
To demodulate the audio of an interfering signal:
1. Tap the Interference button.
2. Tap the Audio tab.
3. Display the trace of the interfering signal.
4. Tap the trace at the peak of the suspected interfering signal to set
the measurement frequency. See Figure 3--23.