The Scope Trigger Menu
Auto-Trig field
Auto-Trig field
The Auto-Trig field allows you to specify whether or not the acquisitions
should wait for the specified trigger condition to occur. When you select the
Auto-Trig field, the field toggles between On and Off. The On and Off fields
are discussed below.
The default selection for the Auto-Trig field is On.
On
When you set auto-trigger to On, the oscilloscope waits 50 ms (20-Hz rate)
for a trigger to occur. If a trigger does not occur within that time, the current
contents of acquisition memory are displayed. The message "Auto triggered"
is displayed if one of the following conditions occurs:
•
No signal is on the input. In this case, the oscilloscope will display a
baseline.
•
There is a signal but the specified trigger condition has not been met
within 50 ms. In this case, the waveform display will not be synchronized
to a trigger point.
Off
When you set auto-trigger to Off, the oscilloscope waits until a trigger is
received before the waveform display is updated. If a trigger does not occur,
the screen is not updated and the message "Waiting for Trigger" is displayed.
Use this mode when:
•
The trigger source signal has less than a 20-Hz repetition rate.
•
The trigger events counter (refer to "Count field") is set so that the
number of trigger events would not occur before 50 ms.
•
When you want to trigger on a specific event only.
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