HP 16533A, User Reference, Page: 81 / 152

Auto-Trig Field
The Auto-Trig field allows you to specify whether or not the acquisitions
should wait for the specified pattern condition to occur. When you touch
the Auto-Trig field, the field toggles between On and Off.
On
When you set auto-trigger to On, the oscilloscope waits for approximately 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:
•
If no signal is on the input. In this case, the oscilloscope will display a
baseline.
•
If there is a signal but the specified pattern condition has not been met.
In this case, the waveform display is not 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, below) is set so that the
number of trigger pattern events would not occur before approximately
50 ms.
•
When you want to trigger on a specific event only.
•
When using pattern duration triggering and the events that meet the
duration specification occur infrequently.
The default selection for the Auto-Trig field is On.
The Trigger Menu
Auto-Trig Field
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