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October 2014
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.
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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.
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.
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.
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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Coupling
: Trigger coupling determines what part of the signal passes to the
trigger circuit. Coupling types include AC, DC, LF Reject and HF Reject.
AC
: AC coupling blocks DC components.
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 8 kHz.
HF Reject
: HF Reject coupling attenuates all signals with a frequency
higher than 150 kHz.
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Holdoff
:A time interval before the oscilloscope responses to next trigger
signal. During this Holdoff period, the trigger system becomes "blind" to
trigger 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.
