RIGOL DS1000B - Manual (Page 78)

RIGOL
User’s Guide for DS1000B series 2-48
display becomes stable on the screen.
Any factor results in the instability of waveforms can be detected by Auto Trigger,
such as the output of Power supply.
NOTE: When horizontal control is set under 50 ms/div, Auto mode allows the
oscilloscope not to capture trigger signal.
 Normal:
The Normal mode allows the oscilloscope to acquire a waveform only when it is
triggered. If no trigger occurs, the oscilloscope keeps waiting, and the previous
waveform will remain on the display.
 Single:
In Single mode, after pressing the Single key, the oscilloscope waits for trigger.
While the trigger occurs, the oscilloscope acquires one waveform then stop.
3. Coupling:
Trigger coupling determines which signal component passing to the trigger
circuit. Coupling types include AC, DC, LF Reject and HF Reject.
 AC: AC coupling blocks DC components and attenuate signal lower than 10 Hz.
 DC: DC coupling passes both AC and DC components.
 LF Reject: LF Reject coupling blocks DC component, and attenuates all signal
with a frequency lower than 10 kHz.
 HF Reject: HF Reject coupling attenuates all signals with a frequency higher
than 100 kHz.
4. Pre-trigger/delayed trigger:
The data is collected before and after trigger.
The trigger position is typically set at the horizontal center of the screen. In the
full-screen display the 6div data of pre-trigger and delayed trigger can be
surveyed. More data (14div) of pre-trigger and 1s delayed trigger can be
surveyed by adjusting the horizontal
knob.
This feature is very useful to study the events that led up to the trigger point.
Everything on the right of the trigger point is called post-trigger information.
Delay range (pre-trigger and post-trigger information) depends on the sweep
speed selected.