Agilent Technologies 54657A, User Manual

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To make phase measurements automatically
Phase shift between two signals can be measured using the Lissajous method.
Refer to the
User and Service Guid e for your oscilloscope for more
information.
With the Measurement/Storage Module installed, phase is automatically
measured and displayed. Measurement is made from the rising edge of the
first full cycle on the input 1 signal, to the rising edge of the first full cycle on
the input 2 signal. The method used to determine phase is to measure delay
and period, then calculate phase as follows:
Phase =
delay
period of input 1
x 360
1
Adjust controls so that a minimum of one full cycle of the signal
connected to input 1 is displayed.
2
Press
Time
.
3
Press the Next Menu softkey until the Define Thresholds softkey is
displayed on the far left side.
4
Press the
Measure Phase
softkey. Phase is measured and displayed on
the screen.
Negative phase values indicate the displayed signal on channel 2 is leading
the signal on channel 1.
Automatic Phase Measurement Hints
If one full cycle of the signal connected to input 1 is not displayed, phase will not
be measured.
User thresholds has no effect on automatic phase measurements. Phase is
always measured at the 50% transition point (threshold level).
When using the delayed timebase, the instrument will attempt to perform the
measurement using the delayed window. If the selected channel 1 edge,
channel 2 edge, and channel 1 period cannot be found in the delayed window,
the main window is used. See "Time Measurements" in the
User and Service
Guide for your oscilloscope for more information.
Operating the Measurement/Storage Module
To make phase measurements automatically
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