User Manual of
OWON
Color Mixed Signal Digital Storage Oscilloscope
45
Term interpretation
1. Source
: Trigger can occur from several sources: Input channels (CH1, CH2), AC Line,
Ext, Ext/5.
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Input
:It is the most commonly used trigger source. The channel will work when
selected as a trigger source whatever displayed or not.
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Ext Trig:
The instrument can trigger from a third source while acquiring data from
CH1 and CH2. For example, you might want to trigger from an external clock or with a
signal from another part of the test circuit. The Ext, Ext/ 5 trigger sources use the
external trigger signal connected to the EXT TRIG connector. Ext uses the signal
directly; it has a trigger level range of +1.6 V to -1.6 V. The EXT/ 5 trigger source
attenuates the signal by 5X, which extends the trigger level range to +8 V to -8 V. This
allows the oscilloscope to trigger on a larger signal
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AC Line:
AC power can be used to display signals related to the power line frequency,
such as lighting equipment and power supply devices. The oscilloscope gets triggered
on its power cord, so you do not have to input an AC trigger signal. When AC Line is
selected as trigger source, the oscilloscope automatically set coupling to DC, set trigger
level to 0V.
2.
Trigger Mode:
The trigger mode determines how the oscilloscope behaves in the absence of a trigger
event. The oscilloscope provides three trigger modes: Auto, Normal, and Single.
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Auto
: This sweep mode allows the oscilloscope to acquire waveforms even when it
does not detect a trigger condition. If no trigger condition occurs while the oscilloscope
is waiting for a specific period (as determined by the time-base setting), it will force
itself to trigger.
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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, if any, will remain on the display. Single: In Single mode, after pressing the
RUN/STOP key, the oscilloscope waits for trigger. While the trigger occurs, the
oscilloscope acquires one waveform then stop.
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Single:
In Single mode, after pressing the RUN/STOP key, the oscilloscope waits for
trigger. While the trigger occurs, the oscilloscope acquires one waveform then stop.
3. Coupling:
Trigger coupling determines what part of the signal passes to the trigger circuit. Coupling
types include AC, DC, LF Reject and HF Reject.
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AC
: AC coupling blocks DC components.
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DC
: DC coupling passes both AC and DC components.
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LF Reject
: LF Reject coupling blocks DC component, and attenuates all signal with a
frequency lower than 8 kHz.
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HF Reject:
HF Reject coupling attenuates all signals with a frequency higher than
150 kHz.
4. Holdoff:
A time interval before the oscilloscope responses to next trigger signal.During
this Holdoff period,the trigger system becomes “blind” to grigger signals.This function
helps to view complex signals such as an AM waveform.Press Holdoff button to activate
“TRIG LEVEL” knob,then turn it to adjust Holdoff time.
