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19.13.
Traces Menu
Live Trace:
toggles the live trace on and off - the live trace (green) is updated by the sweep function.
Ref. Trace:
toggles the reference trace on or off - the reference trace (purple) can be either recalled
from memory or copied from the live trace. If no reference trace has been created or recalled, the key
will have no function.
Note: If the sweep parameters (start/stop or centre/span) are different from their values when the
reference trace was captured, the trace is automatically shifted and scaled so as to correctly represent
the stored trace for the new frequency span. The trace may therefore occupy only a part of the screen
or may be off the screen altogether. An off-screen trace is indicated by a purple arrow at the appropriate
edge of the graticule.
Live > Ref.:
copies the live trace, as currently displayed on the screen, onto the reference trace.
Hi Res/Lo Res:
toggles the screen resolution of the trace area. Hi Res uses 320 x 300 pixels, Lo Res
uses 160 x 150 points where each point is 4 pixels; this provides thicker lines but less resolution.
Video Filter
: toggles the video filter function on or off. When on, an analogue filter is applied to the trace
which attenuates sudden transitions and noise.
Limit Lines
: toggles the limit lines (L1 and L2) on or off. Successive presses step through a sequence:
Both Off > L1 On > L2 On > L1 + L2 On > Both Off. If no limit lines have been created or recalled, the
key will have no function. The colour of Limit Line 1 is red. Limit line 2 is blue.
To exit this menu
and return to the home menu press the Back (Home) hard key, or the grey area at
the top left of the menu.
19.14.
Stores Menu
Each key brings up a dialogue box which includes a scrollable window of existing files, a line for the
currently selected file name, and three keys - OK, Cancel and Delete.
When a file is being stored, a default filename is allocated. This can be overwritten using the on-screen
keyboard. Existing files can be overwritten by selecting them from the files window and pressing OK (a
warning message is displayed).
Existing files can also be deleted by selecting them from the files window and pressing Delete (a warning
message is displayed).
Note:
The store, recall and copy functions are only available when the memory card is inserted.
This menu allows the live trace and the reference trace
to be turned on and off and the live trace to be copied
to the reference trace. It also allows the screen
resolution for the trace area to be changed, and the
video filter function to be turned on or off. The current
status is shown within the menu area.
Traces can be stored to memory as files of amplitude
and frequency (comma-separated-variable format).
These files can be recalled to the reference trace. The
complete set-up of the instrument can be to saved to
files for recall later. The whole screen (traces,
graticule, annotation) can be stored to a bit-map image
file for viewing or printing outside of the application.