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Common Measurement Settings
R&S
®
FSW
420
User Manual 1173.9411.02 ─ 19
Pre-trigger offsets are possible because the R&S
FSW captures data continuously in
the time domain, even before the trigger occurs.
See
Trigger Hysteresis
Setting a hysteresis for the trigger helps avoid unwanted trigger events caused by
noise, for example. The hysteresis is a threshold to the trigger level that the signal
must fall below on a rising slope or rise above on a falling slope before another trigger
event occurs.
Example:
In the following example, the second possible trigger event is ignored as the signal
does not exceed the hysteresis (threshold) before it reaches the trigger level again on
the rising edge. On the falling edge, however, two trigger events occur as the signal
exceeds the hysteresis before it falls to the trigger level the second time.
Trigger level
T
T
T
Trigger
hysteresis
T
Fig. 6-24: Effects of the trigger hysteresis
See
Trigger Drop-Out Time
If a modulated signal is instable and produces occassional "drop-outs" during a burst,
you can define a minimum duration that the input signal must stay below the trigger
level before triggering again. This is called the "drop-out" time. Defining a dropout time
helps you stabilize triggering when the analyzer is triggering on undesired events.
Trigger and Gate Configuration