User`s guide

3 To Set the Horizontal System RIGOL

DS2000 User’s Guide

3-5

X-Y Mode

In this mode, the oscilloscope changes the two channels from voltage-time display

mode to voltage-voltage display mode. Wherein, the X axis and Y axis tracks the

voltages of CH2 and CH1 respectively. The phase deviation between two signals with

the same frequency can be easily measured via Lissajous method. The figure below

shows the measurement schematic diagram of the phase deviation.

According to sinθ=A/B or C/D (wherein, θ is the phase deviation angle between

the two channels and the definitions of A, B, C and D are as shown in the figure

above), the phase deviation angle is obtained, that is:

θ=±arcsin (A/B) or ±arcsin (C/D)

If the principal axis of the ellipse is within quadrant I and III, the phase deviation

angle obtained should be within quadrant I and IV, namely within (0 to π/2) or (3π/2

to 2π). If the principal axis of the ellipse is within quadrant II and IV, the phase

deviation angle obtained should be within quadrant II and III, namely within (π/2 to

π) or (π to 3π/2).

X-Y function can be used to measure the phase deviation occurred when the signal

under test passes through a circuit network. Connect the oscilloscope to the circuit to

II I

III IV

The signal must be

centered horizontally

II I

III IV