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Common Measurement Settings
R&S
®
FSW
421
User Manual 1173.9411.02 ─ 19
T
Drop-Out
T
T
Fig. 6-25: Effect of the trigger drop-out time
See
Drop-out times for falling edge triggers
If a trigger is set to a falling edge ("Slope" = "Falling", see
measurement is to start when the power level falls below a certain level. This is useful,
for example, to trigger at the end of a burst, similar to triggering on the rising edge for
the beginning of a burst.
If a drop-out time is defined, the power level must remain below the trigger level at
least for the duration of the drop-out time (as defined above). However, if a drop-out
time is defined that is longer than the pulse width, this condition cannot be met before
the final pulse, so a trigger event will not occur until the pulsed signal is over!
Drop-Out
T
T
T
Fig. 6-26: Trigger drop-out time for falling edge trigger
For gated measurements, a combination of a falling edge trigger and a drop-out time is
generally not allowed.
Trigger Holdoff
The trigger holdoff defines a waiting period before the next trigger after the current one
will be recognized.
Trigger and Gate Configuration