Advanced Triggering, Search & Navigation, and Segmented Acquisition Labs
3
3000 X-Series Oscilloscopes Advanced Training Guide
57
Your scope’s display should now look similar to
scope’s default rising edge type trigger, we can see pulses that have
various amplitudes. The pulses that have the lower amplitudes are “runt”
pulses. This particular data stream includes both positive runts (pulses
that fail to meet a minimum high level) and negative runts (pulses that fail
to meet a minimum low level). Let’s now set up the scope to trigger on
just positive runt conditions.
9
Press the
[Trigger]
front panel key; then turn the Entry knob to select
Runt
type triggering.
10
Press the
Level Select
softkey to select
Low
.
11
Turn the trigger level knob to set the lower trigger level threshold to be
approximately 1 division above the bottom of the waveform.
12
Press the
Level Select
softkey to select
High
; then turn the Trigger Level
knob to set the upper trigger level threshold to be approximately 1
division below the top of the waveform.
Your scope should now be triggering on positive runt pulses of two
different widths as shown in
. You can also change the polarity
of the runt triggering to either “positive runts only”, “negative runts only”,
or “either polarity runts” using the appropriate softkey selection. Note that
the Agilent 3000 X- Series oscilloscopes can also trigger on runt pulses
that meet a specific time qualification. Based on the scope’s current
timebase setting (100.0 ns/div), we can estimate that the width of these
two positive runt pulses shown in
are approximately 300 ns and
Figure 37 Triggering on positive runts.