R&S RTO6, Руководство пользователя

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Triggers
R&S
®
RTO6
221 User Manual 1801.6687.02 ─ 05
"Auto" The instrument triggers repeatedly after a time interval if the trigger
conditions are not fulfilled. If a real trigger occurs, it takes prece-
dence. This mode helps to see the waveform even before the trigger
conditions are set correctly. The waveform on the screen is not
synchronized, and successive waveforms are not triggered at the
same point of the waveform. The time interval depends on the time
base settings.
"Normal" The instrument acquires a waveform only if a trigger occurs, that is, if
all trigger conditions are fulfilled. If no trigger occurs, no waveform is
acquired and the last acquired waveform is displayed. If no waveform
was captured before, none is displayed.
When no trigger has been found for longer than one second, a mes-
sage box appears that shows the time elapsed since the last trigger.
"Repetitive" The instrument starts acquisition immediately and triggers after a
short time interval independent of the time base settings and faster
than in "Auto" mode. Real triggers are ignored. Use this mode if the
"Auto" mode is too slow.
Remote command:
TRIGger<m>:MODE
on page 1430
Force Trigger
If the acquisition is running in normal mode and no valid trigger occurs, forcing the trig-
ger provokes an immediate single acquisition. Thus you can confirm that a signal is
available and use the waveform display to determine how to trigger on it.
If you need this function frequently, you can add the "Force Trigger" icon to the toolbar.
Remote command:
TRIGger<m>:FORCe
on page 1430
Holdoff mode
Selects the method to define the holdoff condition.
The trigger holdoff defines when the next trigger after the current will be recognized.
Thus, it affects the next trigger to occur after the current one. Holdoff helps to obtain
stable triggering when the oscilloscope is triggering on undesired events.
Holdoff settings are not available if the trigger source is an external trigger input or
serial bus. For the TV trigger, only the "Events" mode is useful.
Example:
You want to analyze the first pulse in a burst of several pulses. At first, you select a
sufficiently slow time base to display the entire burst. Then, you set the holdoff time a
little longer than the length of the burst. Now, each trigger corresponds to the first pulse
in successive bursts, and you can change the time base to display the waveform in
more detail.
The following methods are available:
"Time" Defines the holdoff directly as a time period. The next trigger occurs
only after the "Holdoff time" has passed.
Mode / Holdoff