Datasheet

54
output of the network.
(3) Push the Autoset button, with the oscilloscope turning on the signals of the two channels
and displaying them in the screen.
(4) Turn the Vertical Scale knob, making the amplitudes of two signals equal in the rough.
(5) Push the Acquire button to display the right menu.
(6) In the right menu, select XY Mode as ON. The oscilloscope will display the input and
terminal characteristics of the network in the Lissajous graph form.
(7) Turn the Vertical Scale and Vertical Position knobs, optimizing the waveform.
(8) With the elliptical oscillogram method adopted, observe and calculate the phase
difference (see Figure 0-6).
Figure 0-6 Lissajous Graph
Based on the expression sin (q) =A/B or C/D, thereinto, q is the phase difference angle, and
the definitions of A, B, C, and D are shown as the graph above. As a result, the phase
difference angle can be obtained, namely, q =± arcsin (A/B) or ± arcsin (C/D). If the principal
axis of the ellipse is in the I and III quadrants, the determined phase difference angel should be
in the I and IV quadrants, that is, in the range of (0 - π /2) or (3π / 2 - 2π). If the principal axis of
the ellipse is in the II and IV quadrants, the determined phase difference angle is in the II and
III quadrants, that is, within the range of (π / 2 - π) or (π - 3π /2).
The signal must be
centered and kept in the
horizontal direction.