26
3000 X-Series Oscilloscopes Advanced Training Guide
2
Oscilloscope Familiarization Labs
26
After the Cursors menu closes, turn the Entry knob until the X1 cursor
is on top of the highest frequency peak (near the left side of the
display).
27
Push the Cursors knob again and select the
X2
cursor.
28
After the Cursors menu closes, turn the Entry knob until the X2 cursor
is on top of the 2nd highest frequency peak.
The frequencies at the X1 and X2 cursor locations are displayed near the
bottom of the scope’s display.
Let’s now verify the fundamental frequency of this signal using the scope’s
“counter” measurement.
29
Press the
[Meas]
front panel key.
30
Press the
Type
softkey; then turn the Entry knob until the arrow points
to
Counter
.
31
Now either push the Entry knob to select this measurement, or press
the
Add Measurement
softkey.
The “counter” measurement measures the average frequency over a fixed
gate time to provide a very high resolution (5 digits) measure of frequency,
similar to a standalone counter. But the measurement requires that the
input signal be repetitive.
The “frequency” measurement measures the period of just one cycle of the
signal, and then computes the frequency by taking the reciprocal.