OWON VDS Series - Manual (Page 17)

Note: Different machines have different ranges of time base, here just take VDS3102 for instance.
The further from the center, the higher the changing speed is.
Keyboard Shortcuts
←: Time base decreases one level
→: Time base increases one level
See also:
11.How to zoom the waveform
4.How to Set the Trigger System
Trigger determines when VDS starts to acquire data and display waveform. Once trigger is set correctly, it can convert the unstable display to
meaningful waveform.
When VDS starts to acquire data, it will collect enough data to draw waveform on left of trigger point. VDS continues to acquire data while waiting
for trigger condition to occur. Once it detects a trigger it will acquire enough data continuously to draw the waveform on right of trigger point.
Click to show Function menu, choose "Trigger".
You can also click in the right bottom window to show it.
Trigger Control
The oscilloscope provides two trigger types: single trigger and alternate trigger.
Single trigger: Use a trigger level to capture stable waveforms in two channels simultaneously.
Alternate trigger: Trigger on non-synchronized signals.
The Single Trigger and Alternate Trigger menus are described respectively as follows:
Single trigger
1. In Trigger menu, choose "Single" (the chosen label has a mark).
2. Choose Source.
3. Choose Mode.
Single trigger has four modes: edge trigger, video trigger, slope trigger and pulse trigger.
Edge Trigger: It occurs when the trigger input passes through a specified voltage level with the specified slope.
Video Trigger: Trigger on fields or lines for standard video signal.
Slope Trigger: The oscilloscope begins to trigger according to the signal rising or falling speed.
Pulse Trigger: Find pulses with certain widths.
The four trigger modes in Single Trigger are described respectively as follows:
Edge Trigger
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