Tektronix RSA6100A Series, Help Manual

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Controlling the Acquisition of Data > Using Triggers to
Capture Just What You Want > Triggering Advanced Tab (Triggering)
400 µs), it will appear to the analyzer that the signal is continuously in violation. Shorter and Inside
settings will not produce a trigger in this situation.
Advanced Tab (Triggering)
Menu Bar: Setup > Trigger > Advanced
Application Toolbar: Trig > Advanced
Allows you to set parameters for trigger position and holdoff settings.
Setting Description
Position Sets the point along the acquisition record the trigger event should occur.
Delay Sets how long after the trigger event speci fi ed by the Position setting, the spectrum
analyzer should wait before actually initiating the trigger event.
Holdoff Prevents triggers until there have been no trigger events for at least the speci fi ed time.
Range: 20 ns–10 s.
Trigger each frequency
segment in Swept acquisition
mode Sets the spectrum analyzer to wait for a trigger for each acquisition in a swept spectrum
or other measurement requiring multiple acquisitions worth of span.
xxx
Holdoff
Holdoff on the spectrum analyzer does not work exactly like the traditional Holdoff setting on an
oscilloscope. On an oscilloscope, once the instrument triggers, the holdoff setting causes the oscilloscope
to refuse to accept another trigger until the holdoff time has expired. On the spectrum analyzer, once a
trigger event is identi
fi ed, the instrument determines how long it has been since the previous trigger event
occurred and if the time since the previous trigger event is greater than the holdoff time, the trigger event
is accepted and an acquisition is completed. If the time since the previous trigger event is less than the
holdoff time, the latest trigger event is ignored (no acquisition occurs) and the holdoff time count restarts.
The most common reason for using holdoff is ensuring that the instrument triggers on the fi rst pulse in a
burst. For this application, the difference between the spectrum analyzer holdoff and the traditional
oscilloscope holdoff has no effect on acquisitions.
The case where the difference can be noticed is when the time between trigger events is always less than
the speci
fi ed holdoff time. An oscilloscope will trigger on the fi rst event after the holdoff time expires,
no matter how short the time has been since the most recent rejected trigger event. In such a situation,
the spectrum analyzer will not ever trigger because it requires that there are no trigger events during
the holdoff time before an accepted trigger event.
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RSA6100A Series Real-Time Spectrum Analyzers Help