GRATTEN GA1022CAL, Руководство пользователя

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[FORCE]
No matter whether the oscilloscope detects the trigger, the key can be pressed to
perform force trigger once so as to finish acquisition of the current waveform. The key
is mainly applied to “Normal” and “Single” in the trigger modes.
Pre-trigger/delay trigger
The key is used for triggering the sampled data before/after the event.
The trigger position is generally set in the horizontal center of the screen, so that the
pre-trigger and delay information can be observed. The horizontal [POSITION] knob
can be further revolved to regulate horizontal displacement of the waveform so as to
check more pre-trigger information or delay trigger information. For instance, if burrs
generated by the circuit are caught, the causes of generation of the burrs may be found
out by observing and analyzing the pre-trigger data.
Attention: pre-trigger and delay trigger are invalid at a slow scan state.
2.7.1 Signal source
The “Signal source” option can be used for selecting a signal as a trigger source for the
oscilloscope. The signal source may be any signal connected to channels
BNC(CH1,CH2), external triggers BNC(EXT,EXT/5) or an AC power line (AC Line is only
used for “Edge” trigger). The EXT/5 setup option is used for expanding the external
trigger electric level range.
2.7.2 Types
This series of oscilloscopes provide five trigger types: Edge, Pulse, Video, Slope and
Alternation.
1. Edge trigger: the most basic as well as the most common trigger type,
as shown in figure 2-29.