38
20.9. Creating and Displaying Limit Lines
The two current lists are selected by pressing Line1 or Line 2 at the top of the screen (the blue highlight
shows which is selected). The window shows up to six points within the current list. Use the scroll
arrows to move through the list.
The two dotted lines below the window are the two numeric editing areas (frequency and amplitude).
The editing cursor can be moved between the two using the Navigator hard keys (or by touching the
screen). The Palm keyboard is used to enter or modify numbers, the cursor can be moved using the
Navigator keys or by touching the screen at the desired position.
Note that amplitudes are entered in dBm or dBµV depending upon the setting chosen in the Level menu.
Existing values are automatically converted when the dBm/dBµV mode is changed.
Once a new frequency/amplitude point has been created in the editing area, it can be added to the
current list by pressing the Add key below. The maximum number of frequency/amplitude points in a
limit line list is 400.
To modify or delete an existing point, it can be brought into the editing area by selecting it from within the
list window. To delete the point press the Del key. To modify the point, edit it with the Palm keyboard
and then press the Mod key.
To start a completely new list, press the New key. This deletes all points in the current list. To exit the
editor screen while saving all of the changes, press the Finish key. To exit without saving any changes
press the Cancel key.
Note that frequency/amplitude points are automatically placed in ascending frequency order. However
where two identical frequency points are included to create a step change, the “from” amplitude point
must appear above the “to” amplitude point in the list.
Limit lines can be stored and recalled to and from the memory card in a similar way to traces. The store
and recall procedures are similar to those described in section 20.8 . Note that a limit line will be stored
from (or recalled to) either Line 1 or Line 2 depending upon which is currently selected.
Limit lines are created by defining a list of frequency &
amplitude points (minimum 2). Straight lines are drawn
between these points. Where a frequency is repeated
with different amplitudes, the line becomes vertical
representing a step change.
Two limit lines can be displayed simultaneously. The
limit line editor controls the current lists for these two
lines. Limit line lists can be created, modified, stored
and recalled from this screen.
Note that the display of the Limit Lines is controlled
from the Traces menu.
Creating or Editing Limit Lines
The editor is accessed using the Lim. Line Editor key
within the Stores menu.
Values are entered using the Palm numeric keyboard -
- see section 20.11. Because of its small size, it is
likely to require the use of the Palm stylus or similar
pointing device.