Scan Modes - Teledyne HDO9000 Operator's Manual

When setting up WaveScan, you can customize the presentation by choosing different WaveScan
display features, called
events are found, such as stopping the acquisition or sounding an alarm.
Note: The instrument reverts to Real-time sampling mode when WaveScan is enabled.

Scan Modes

The Scan Mode determines the type of search to be performed. Select the Mode along with the
Source trace to be searched on the main WaveScan dialog. For each mode, different controls appear
on the WaveScan dialog, providing additional inputs to the search criteria. Make the appropriate
entries in these fields before starting the search.
Edge Mode
Edge Mode is used for detecting the occurrence of edges. Events that meet the threshold level are
captured and tabulated. When the acquisition is stopped, scan filters can be applied to the edges to
find specific characteristics. Edge Mode settings are:
Slope. Choose Pos, Neg, or Both.
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Level is (set in...). Choose Percent or Absolute.
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Percent/Absolute Level. Enter a threshold value as a percentage of Top to Base or voltage
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level.
Non-monotonic Mode
Non-monotonic Mode looks for edges that cross a threshold more than once between high and low
levels. All events that meet the criteria of slope, hysteresis, and level are presented in a table and
highlighted in the source trace. The value displayed in the table is the difference of the max. and min.
of the non-monotonicity. This can be confirmed with cursors. The hysteresis value is used to
eliminate noise. A non-monotonicity is detected only when its amplitude is greater than the
hysteresis. Therefore, when setting a hysteresis level, set a value that is greater than the amplitude
of the noise. Non-monotonic Mode settings are:
Slope. Choose Pos, Neg, or Both.
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Hysteresis is (set in...). Choose Division, Percent, Absolute.
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Division/Percent/Absolute. Enter hysteresis level in the selected unit.
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Levels are (set in...). Choose Percent, Absolute, or Pk-Pk%.
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High/Low Level. Enter top and bottom thresholds in the selected unit.
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Runt Mode
Runt Mode looks for pulses that fail to cross a specified threshhold. You can search for positive-
going or negative-going runts, or both. An adjustable hysteresis band is provided to eliminate noise.
In the case of negative-going runt pulses, the value displayed in the table is the difference (delta) of
the high level of the signal and the runt amplitude (i.e., where the runt bottoms out). This can be
confirmed by placing cursors on the runt pulse and reading the delta Y value in the trace labels. In the
Scan Views. Optionally, set actions to occur automatically when unusual
Analysis Tools
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