LeCroy SDA, Operator'S Manual

Page: 241 / 397

SDA Operator’s Manual
The next figure shows a part of the Excel workbook:
Here we see the gated waveform that has been created in Excel. The Mean parameter during the
region of interest (ROI) is placed in cell H3.
How Does this Work?
The amplitude of the signal is about 0.3 volts, and the screen height is 0.4 volts, as derived from
cells F7 and Fx. A threshold value for amplitude was calculated by placing 0.5 * (Fy – Fx) in cell
A4.
Remember that in the instrument the sources were defined to be A10 and B10. This means that
the first point on the waveform will be read into A10, and, since the waveform has 500 points, the
last point will be read into A510. The same holds true for F2 and column B, since F2 is assigned
as Source2, and data is defined to write into column B starting with cell B10.
To create the gating function in column C, the cell C10 was given the following formula:
IF ( ( B10 – B9) > $A$4, 1 – C9, C9). This was copied down the column. Column D, the output
column, is simply A * C.
The output was defined as cell H3.
The required mean in cell H3 is given by SUM (D10 : D509) / SUM (C10 : C509), for a 500 point
waveform.
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