Example 6: Video Signal Trigger - Owon SDS1104 User Manual

6.Demonstration
The signal must be
centered and kept in the
horizontal direction.
Figure 6-6 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).

Example 6: Video Signal Trigger

Observe the video circuit of a television, apply the video trigger and obtain the stable
video output signal display.
Video Field Trigger
For the trigger in the video field, carry out operations according to the following
steps:
(1) Push the Trigger Menu button to display the right menu.
(2) In the right menu, select Type as Single.
(3) In the right menu, select Single as Video.
(4) In the right menu, select Source as CH1.
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