Rigol MSO4000 User Manual page 74

RIGOL
The X-Y function can be used to measure the phase deviation when the signal under
test passes through a circuit network. Connect the oscilloscope to the circuit to
monitor the input and output signals of the circuit.
Application example: measure the phase deviation of the input signals of two
channels.
Method 1: Use Lissajous method
1. Connect a sine signal to CH1 and then connect a sine signal with the same
frequency and amplitude but a 90° phase deviation to CH2.
2. Press AUTO and enable X-Y mode. Then, press XY1 to select "On".
3. Roate VERTICAL
center of the screen and roate VERTICAL
to observe. At this point, the circle as shown in the figure below should be
displayed.
4. As shown in the figure above, the distances from the crossing points of axis and
the circle to the origin of the coordinates are approximately equal. Thus, the
phase deviation angle θ=±arcsin1=90°.
Note:
In Y-T mode, the oscilloscope could use any sample rate (within the guaranteed

range) to capture the waveform. The maximum sample rate of X-Y mode is 2.0
GSa/s. Generally, reducing the sample rate can improve the displayed Lissajous
figure.
3-6
POSITION of CH1 and CH2 to display the signals at the
3 To Set the Horizontal System
SCALE to make the signals easy
MSO4000/DS4000 User's Guide