UNI-T UTD2000M, Operating Manual

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UTD2000M User Manual
Trigger Type
Press TRIGGER
MENU key, then press F1, after that, turn “
MULTIPURPOSE
” knob to select trigger type. Press
“
MULTIPURPOSE
” knob down to select less amplitude pulse triggering.
Signal Source
Press F2 to switch among trigger source where you can choose one from CH1, CH2, EXT, EXT/5, AC LINE and
ALTER. Once complete the setting, current signal source will be displayed at a lower position of the screen.
Notes: Only by selecting those channels that has signal input as the source for triggering, can we get reliable
triggered waveform.
Pulse Polarity
Press F1 to select the pulse polarity that can arouse less amplitude pulse triggering.
Negative polarity: trigger on negative less amplitude pulse.
Positive polarity: trigger on positive less amplitude pulse.
Triggering Condition
Press F2 to set triggering condition for less amplitude pulse triggering.
Irrelevant: do not set triggering condition for less amplitude pulse triggering.
>
：
Trigger when the less amplitude pulse width is larger than the preset lower limit of pulse width.
<
：
Trigger when the less amplitude pulse width is smaller than the preset upper limit of pulse width.
=
：
Trigger when the less amplitude pulse width equals the preset pulse width.
Notes: UTD2202HM&CM does not have less amplitude pulse triggering.
2.4.6 Trigger Hold Off Settings
The function of trigger hold off is to observe complicated waveform (i.e. pulse string). Hold off time refers to
the waiting time before oscilloscope restarts its trigger circuit. During such time, the oscilloscope won’t be
triggered until such time ends. For example, see Fig. 2 ‐ 23, which is a pulse string. If we demand trigger to occur at
the first pulse of this pulse string, then we can set hold off time to be the width of this pulse string.
Table 2 ‐ 14 Trigger Hold off Menu
Menu Setting Description
Window —— Press F1 key to enter into “main window”
Window Expansion —— Enter into window expansion menu, see Table 2 ‐ 8
Hold off 96.0000ns
～
1.50000s Use “MULTIPURPOSE” to adjust hold off time
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