Keysight Technologies 3458A Guide D'utilisation page 197

Level Triggering
When digitizing, it is important to begin sampling at some defined point on the
input signal such as when the signal crosses zero volts or when it reaches the
midpoint of its positive or negative peak amplitude. Level triggering allows you to
specify when (with respect to voltage and slope) to begin sampling. For example,
Figure 5-5
positive slope.
Figure 5-5
Level triggering examples
For DCV and direct sampling, level triggering can be used as the trigger event
(TRIG LEVEL command) or the sample event (NRDGS n, LEVEL command). For
sub-sampling, level triggering can be used as the sync source event only (the sync
source event is discussed later in this chapter under Sub-Sampling). The program
examples in this section use the DCV method of digitizing and the 10 V range.
Refer to
for complete programs showing specific information on how to use level triggering
with each digitizing method.
The LEVEL command specifies the level triggering voltage as a percentage of the
measurement range. {The ranges are shown later in this chapter under the
discussions for each digitizing method,) The LEVEL command also specifies the
coupling (AC or DC) to the level detection circuitry.
Keysight 3458A User's Guide
shows sampling beginning as the input signal crosses 0 V with a
Level triggering at zero crossing, positive slope
DCV Digitizing, Direct-Sampling, and
Digitizing
Sub-Sampling later in this chapter,
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