LeCroy SDA, Operator'S Manual

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3. If you want to change the parameter listed, or a measurement characteristic, touch the
parameter button ( P1 for example) alongside the check box. A pop-up menu of
parameters categorized by type appears. To display parameter icons only, touch the icon
button at the bottom of the menu. To display the icons in list form, along with an
explanation of each parameter, touch the list button . Use the Up/Down buttons to
scroll through the list of icons.
4. When you make a selection from the parameter icon menu, the setup dialogs for that
parameter appear. You can then change the waveform source and other conditions of the
parameter.
5. If you are setting up an "@level" parameter, make selections for Level type (percent or
absolute), Slope (positive, negative, both), and Hysteresis level.
6. Touch the Gate tab, and set the position of the gate posts.
From a Vertical Setup Dialog
1. In the "Cx Vertical Adjust" dialog, touch the Measure button .
2. Select a parameter from the pop-up menu. (The Actions for trace source defaults to the
channel or trace whose dialog is open. If a parameter, it goes into the next "available"
parameter, or the last one if all are used.)
3. Select another parameter or touch Close .
From a Math Setup Dialog
1. In the "Fx" dialog, touch the Measure button .
2. Select a parameter from the pop-up menu. (The Actions for trace source defaults to the
channel or trace whose dialog is open. If a parameter, it goes into the next "available"
parameter, or the last one if all are used.)
3. Select another parameter or touch Close .
Parameter Calculations
Parameters and How They Work
Determining Top and Base Lines
Proper determination of the top and base reference lines is fundamental for ensuring correct
parameter calculations. Analysis begins by computing a histogram of the waveform data over the
time interval spanned by the left and right time cursors. For example, the histogram of a
waveform transitioning in two states contains two peaks (see Figure 1 as follows).
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