Making Low Frequency Measurements With The Scope - Fluke 91 Series II User Manual

ScopeMeter Test Tool Tutorial
MAKING LOW FREQUENCY
MEASUREMENTS WITH THE SCOPE
Connection
Connect the red scope probe from INPUT A to TP4 on the
Demo Board. Remove the grey Scope probe.
Making the Measurement
1. Reset the ScopeMeter test tool (
2. Press to select the SCOPE mode.
3. Press .
To find the waveform, do the following:
4. Press .
5. Use to select AC coupling (indicated on the top
left of the display).
This technique was used to display the waveform around
the ground level. The ground icon ( ) on the right side of
the display identifies the ground level.
Look at the display and notice that the waveform
occassionally makes larger changes in level. The
Continuous Auto Set tries to find the best trigger level. To
trigger on low frequency waveforms, you have to set the
trigger level manually.
6. Press
7. Use
8. Use
The ScopeMeter test tool is in the Free Run mode, which
+ ). updates the display if a trigger is not found within 100 ms of
starting the acquisition. For slow waveforms, Free Run
must be off to prevent false triggering. To accomplish this:
9.
10. Press
11. Use
12. Use
13. Press
Most of the time the displayed waveform remains still and
the status NOTRIG appears in the top right display. This
status message changes to RUN when the large level
occurs and indicates that triggering has taken place. Adapt
the range and the time base to see the waveform.
.
to higlight "trigger level", and press
select.
to adjust the trigger level to one
division above ground " " level.
Press .
to open the MORE TRIGGER menu.
to highlight TRACE START, and press
to open the list box.
to highlight "wait for trigger", and press
to select.
to close the window.
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