Tektronix DPO2304SX, Печатная инструкция

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After a trigger event, the instrument will not accept another trigger event until after the holdoff value is exceeded. Holdoff is
usually specified in units of time, but other units may be used.
Trigger holdoff (Random)
When Trigger Holdoff is set to Random, the instrument delays the trigger a random amount of time between triggers. This means
that successive acquisitions are unrelated to the previous trigger signal.
Trigger holdoff (Time)
After a trigger event, the instrument will not accept another trigger event until after the holdoff value is exceeded. Holdoff is
usually specified in units of time, but other units can be used.
When the Trigger Holdoff is set to Time, you can manually adjust the value with the multipurpose knob. Use this option when the
signal that you want to trigger on has several possible trigger points. Use the Trigger Holdoff control to delay the trigger system
for a specified amount of time between triggers so that you can obtain a stable display.
Set the trigger level
The trigger level determines the voltage level where the trigger point occurs.
To use.
■
Adjust the trigger level with the front-panel Trigger Level knob.
■
Click in the Level entry box in a Trigger control window and use the multipurpose knob to adjust the level.
Select the trigger on options
Select a value from the Trigger On drop-down list to specify where the trigger will occur on the video signal. The Trigger On drop-
down list contains the options Field, All Lines, and Line #.
■ If you select Field, use the drop-down list to select Odd, Even, or All.
■ If you select Line #, click in entry field and use the multipurpose knob to set the line number. Line numbers wrap when their
limits are reached. The range of line numbers depends on the chosen Format.
NOTE. If you select the NTSC format, use the multipurpose knob to first scroll through all of the odd lines, and then the even
lines.
Select the bus trigger on data
In the Trigger On drop-down menu, select the type of data to trigger on. The available selections are different for each bus type.
Select the glitch trigger polarity
The Polarity buttons set the glitch polarity.
■ Click Pos to trigger on a positive-going pulse.
■ Click Neg to trigger on a negative-going pulse.
■ Click Either to trigger on positive or negative glitches.
Oscilloscope reference
DPO70000SX, MSO/DPO70000DX, MSO/DPO70000C, DPO7000C, and MSO/DPO5000B Series 835