Selecting the Segment

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Using Spectrum Analyzer Features

Using limit-line Functions

Press SEGMENT TYPE , then FLAT, SLOPE, or POINT to specify the segment type. The segment type determines how to connect the coordinate point of the current line segment with the coordinate point of the next line segment. The segment type determines whether the line segment is horizontal, vertical, sloped, or a single point. The three segment types are:

1.Flat draws a zero-slope line between the coordinate point of the current segment and the.coordinate point of the next segment, producing limit-line values equal in amplitude for all frequencies or times between the two points. If the amplitude values of the two segments differ, the limit-line will “step” to the value of the second segment. See Figure 3-7.

2.Slope draws a straight line between the coordinate point of the current segment and the coordinate point of the next segment, producing limit-line values for all frequencies between the two points.

3.Point specifies a limit value for the coordinate point. It specifies a limit at a single frequency or time, and for no other frequency/time points. For an upper limit line, a point segment is indicated by a line drawn from the coordinate point, vertically off the top of screen. For a lower limit line, a point segment is indicated by a line drawn from the coordinate point, vertically off the bottom of screen. The point segment type should be used as the last segment in the limit-line table. However, if the last segment in the table is not specified as the point segment type, an implicit point is automatically used. (If a visible point segment at the right-hand edge of the display is not desired, add an explicit last point segment to the limit-line table that is higher in frequency than the stop frequency.)

Figure 3-7 demonstrates the different segment types.

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