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Acquisition and Waveform Setup
R&S
®
RTM20xx
15
User Manual 1317.4726.02 ─ 01
value of several adjacent sample points of the same waveform and displays it. The result
is a moving average that uses the full data and can be used for non-periodic signals.
2.1.2.3
Acquisition Control
You can run the R&S
RTM in two ways:
●
Continuous: the instrument acquires data until you stop it manually.
●
NxSingle: the instrument samples and processes a specified number of acquisitions.
The determining point of an acquisition is the trigger. The instrument acquires continu-
ously and keeps the sample points to fill the pre-trigger part of the waveform record. When
the trigger occurs, the instrument continues acquisition until the post-trigger part of the
waveform record is filled. Then it stops acquiring and waits for the next trigger. When a
trigger is recognized, the instrument will not accept another trigger until the acquisition is
complete.
The trigger modes define how the instrument triggers:
●
Normal: The instrument acquires a waveform only if a real trigger occurs, that is, if
all trigger conditions are fulfilled.
●
Auto: The instrument triggers repeatedly after a fixed time interval if the trigger con-
ditions are not fulfilled. If a real trigger occurs, it takes precedence. If the real trigger
is faster than the auto trigger, both modes are virtually the same.
In practice, both trigger modes are useful: The auto mode lets you see the signal with
very little adjustment, while the normal mode selects the interesting part of the waveform.
If you want to acquire a specified number of waveforms with NxSingle, make sure to
select the normal trigger mode. Thus you get only the required number of interesting
acquisitions.
See also:
2.1.3 Horizontal System
As described before in
chapter 2.1.2.3, "Acquisition Control"
the determining point of the waveform record.
Two parameters set the position of the horizontal acquisition window in relation to the
trigger point:
time reference
and
trigger offset
. Using these parameters, you choose
the part of the waveform you want to see: around the trigger, before, or after the trigger.
Basics