194 Keysight InfiniiVision 2000 X-Series Oscilloscopes User's Guide
14 Measurements
Frequency
Frequency is defined as 1/Period. Period is defined as the time between the
middle threshold crossings of two consecutive, like-polarity edges. A middle
threshold crossing must also travel through the lower and upper threshold levels
which eliminates runt pulses. The X cursors show what portion of the waveform is
being measured. The Y cursor shows the middle threshold point.
See Also • “To isolate an event for frequency measurement" on page 194
To isolate an event for frequency measurement
The following figure shows how to use Zoom mode to isolate an event for a
frequency measurement.
You may need to change the measurement window setting so that the
measurement is made in the lower, Zoom window. See “Measurement Window
with Zoom Display" on page 200.
If the waveform is clipped, it may not be possible to make the measurement.
Figure 35 Isolating an event for Frequency measurement