LeCroy DDA 7 Zi series, Руководство оператора

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WavePro 7Zi
259
WP700Zi-OM-E-RevA
the Limits button to set up a precise pulse-width range by setting Lower Limit and Upper Limit
values, using the slider bar , pop-up keypad button, or the Default button.
OR
Touch the Out Of Range button on some oscilloscopes and perform the previous part of this step
for In Range triggering.
Note : Use the TriggerScan tab to run the Trainer (a wizard-like tool to configure triggers), Save , and Load
trigger setups for reuse.
Trigger Setup Considerations
Trigger Modes
1.
A
UTO
mode causes the scope to sweep even without a trigger. An internal timer triggers the sweep so that
the display remains, even when the signal does not cause a trigger.
2. In
N
ORMAL
mode, the scope sweeps only if the input signal reaches the set trigger point. Otherwise it
continues to display the last acquired waveform.
3. In
S
INGLE
mode, only one sweep occurs each time you press the button.
4.
S
TOP
mode inhibits all sweeps until you select one of the other three modes.
Determining Trigger Level, Slope, Source, and Coupling
Level defines the source voltage at which the trigger circuit generates an event (a change in the input signal that
satisfies the trigger conditions). The selected trigger level is associated with the chosen trigger source. Note that
the trigger level is specified in volts and normally remains unchanged when the vertical gain or offset is modified.
The Amplitude and Range of the trigger level are limited as follows:
x
±5 screen divisions with a channel as the trigger source
x
±400 mV with EXT as the trigger source
x
±4 V with EXT/10 as the trigger source
x
±40 mV with EXT*10 as the trigger source
x
none with LINE as the trigger source (zero crossing is used)
Note: Once specified, Trigger Level and Coupling are the only parameters that pass unchanged from trigger
mode to trigger mode for each trigger source.
Coupling refers to the type of signal coupling at the input of the trigger circuit. Choices of trigger coupling vary by
scope model.
With DC coupling, all of the signal's frequency components are coupled to the trigger circuit for high-frequency
bursts.
Slope determines the direction of the trigger voltage transition used for generating a particular trigger event.
Choose Positive , Negative , or Either from the slope choices. Like coupling, the selected slope is
associated with the chosen trigger source.