Table of Contents
Advertisement
Lab #2: Using Zoom Display to Perform Gated Measurements
When performing automatic parametric measurements, such as positive
pulse width measurements, on an exactly repetitive input signal, such as a
simple sine wave or square wave, it really doesn't matter which particular
pulse the scope chooses to make the measurement on; each pulse is the
same. But what if the input signal you are probing is more complex; where
each pulse has unique parametric characteristics? In this case, you would
first need to set up the scope to trigger at a unique point in time on the
complex signal, and then you would need to set up the scope's
measurements in such a way that the scope would be more selective as to
which pulse it chooses to perform measurements on. In this lab you will
learn how to perform selective, or "gated", measurements on specific
pulses using the scope's Zoom display mode.
1
2
3
4
5
6
7
8
9
10
With the scope's trigger holdoff feature turned on and set to 4.0 µs, the
scope now triggers on the 1st rising edge of the burst, disarms triggering
for 4.0 µs, and then re- arms triggering after the last pulse in the burst so
that the scope will again trigger on the 1st pulse during the next
repetition of the burst. We have now established a stable and unique
trigger point on this complex digital signal using Trigger Holdoff. You can
learn more about Trigger Holdoff during
Burst using Trigger Holdoff"
2000 X-Series Oscilloscopes Advanced Training Guide
Connect the channel- 1 probe to the Demo 1 terminal and ground.
Press the [Default Setup] key on the scope's front panel.
Press [Help]; then press the Training Signals softkey.
Using the Entry knob, select the Digital Burst with Infrequent Glitch signal;
then press the Output softkey to turn it on.
Set channel- 1's V/div setting to 1.0 V/div.
Set channel- 1's position/offset setting to approximately 2.0 V in order to
center the waveform on- screen.
Push the trigger level knob in order to automatically set the trigger
level at approximately 50% (~1.7 V).
Set the scope's timebase to 1.000 µs/div.
Press the [Mode/Coupling] front panel key near the trigger level knob.
Press the Holdoff softkey; then turn the Entry knob clockwise to set the
trigger holdoff value to 4.000 µs.
Oscilloscope Familiarization Labs
"Lab #7: Triggering on a Digital
on page 40.
2
19
Advertisement
Table of Contents
