Fluke ScopeMeter 196 Manual Do Utilizador

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Triggering on Waveforms
Triggering on Pulses
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Finding Missing Pulses
The next example covers finding missing pulses in a train
of positive pulses. In this example it is assumed that the
pulses have a 100 ms distance between the rising edges.
If the time accidently increases to 200 ms, a pulse is
missing. To set the test tool to trigger on such missing
pulses, let it trigger on gaps bigger than about 150 ms.
Do the following:
1
Display the 
TRIGGER 
key labels.
2
Open the Trigger Options menu.
3
Select Pulse Width on A... to
open the Trigger on Pulse
Width 
menu.
4
Select the positive pulse icon to
trigger on the gap between the
positive pulses, then jump to
Condition.
5
Select >t, then jump to Update.
6
Select On Trigger.
The test tool is now prepared to trigger on pulse gaps.
Observe that the trigger menu at the bottom of the
screen has been adapted to set the pulse condition: