Technical data

5-8
Operating Concepts
Sweep Types
frequencies. If no list has been entered, the message CAUTION: LIST TABLE EMPTY is displayed. A
tabular printout of the frequency list data can be obtained using the LIST VALUES, function in the copy
menu.
Stepped Edit List Menu
The EDIT LIST, softkey within the sweep type menu provides access to the edit list menu.
This menu is used to edit the list of frequency segments (subsweeps) defined with the edit subsweep
menu, described next. Up to 30 frequency subsweeps can be specified, for a maximum of 1601 points. The
segments do not have to be entered in any particular order: the analyzer automatically sorts them and
shows them on the display in increasing order of start frequency. This menu determines which entry on the
list is to be modified, while the edit subsweep menu is used to make changes in the frequency or number of
points of the selected entry.
Stepped Edit Subsweep Menu
Using the EDIT, or ADD, softkey within the edit list menu will display the edit subsweep menu. This menu
lets you select measurement frequencies arbitrarily. Using this menu it is possible to define the exact
frequencies to be measured on a point-by-point basis. For example, the sweep could include 100 points in a
narrow passband, 100 points across a broad stop band, and 50 points across the third harmonic response.
The total sweep is defined with a list of subsweeps.
The frequency subsweeps, or segments, can be defined in any of the following terms:
• start/stop/number of points
•start/stop/step
• center/span/number of points
• center/span/step
• CW frequency
The subsweeps can overlap, and do not have to be entered in any particular order. The analyzer sorts the
segments automatically and lists them on the display in order of increasing start frequency, even if they are
entered in center/span format. If duplicate frequencies exist, the analyzer makes multiple measurements
on identical points to maintain the specified number of points for each subsweep. The data is shown on the
display as a single trace that is a composite of all data taken. The trace may appear uneven because of the
distribution of the data points, but the frequency scale is linear across the total range. Once the list
frequencies have been defined or modified, the list frequency sweep mode can be selected with the LIST
FREQ [STEPPED], softkey in the sweep type menu. The frequency list parameters can also be saved with
an instrument state.
Swept List Frequency Sweep (Hz)
The LIST FREQ [SWEPT] softkey activates a swept list frequency sweep, one of two list frequency sweep
modes. The swept list mode allows the analyzer to sweep a list of arbitrary frequency points which are
defined and modified in a way similar to the stepped list mode. However, this mode takes data while
sweeping through the defined frequency points, increasing throughput by up to 6 times over a stepped
sweep. In addition, this mode allows the test port power and IF bandwidth to be set independently for each
segment that is defined. The only restriction is that you cannot specify overlapping frequency segments.
Similar to stepped list mode, the LIST FREQ [SWEPT] softkey also provides access to the segment menu.
However, swept list mode expands the way segments can be defined. Refer to the following information on
how to enter or modify the list segments.
Swept Edit List Menu
The EDIT LIST, softkey within the sweep type menu provides access to the edit list menu. The function of
this menu is the same as in the stepped list mode.