Using Spectrum Analyzer Features
Using limit-line Functions
•The upper and lower limit-line table format is accessed by Edit Up/Low With the upper and lower limit-line table format, the upper and lower limit-line coordinates can be entered at the same time: the frequency (or time), upper amplitude, lower amplitude, and type are specified. The frequency (or time) and upper amplitude comprise the coordinate point for the upper limit line; the frequency (or time) and lower amplitude value comprise the coordinate point for the lower limit line. It is not necessary to specify both an upper- and lower-amplitude component for every frequency component. Three asterisks in the table indicate that an amplitude value has not been entered for the segment.
•The mid/delta limit-line table format is accessed by Edit Mid/D&t . Like the upper and lower limit-line table format, the mid/delta limit-line table format provides a means of specifying the upper and lower limit lines at the same time. Unlike the upper and lower table format, the amplitude values are specified as a middle amplitude value with a delta: the upper and lower limit lines are then drawn at an equal positive and negative distance from the middle amplitude. With the mid/delta format, the frequency (or time) and the mid-amplitude plus the delta comprise the upper limit line; the frequency (or time) and the mid-amplitude minus the delta comprise the lower limit line. The difference between the mid/delta format and the upper/lower format is the way the amplitude values are entered; however, in both formats, the frequency coordinate begins a segment. The mid/delta format can be used if the upper and lower limit lines are symmetrical with respect to the amplitude axis.
N O T E
Editing a limit line table can be done using a different format than the one that was used for creating it.