Furuno FA Manual page 207

6. With the MARK box selected, roll the wheel to choose mark desired and then
push the left button. See the list on page 5-5 for available marks.
7. Push the left button again. The cursor jumps into the effective display area
and the guidance box reads "MARK / EXIT."
8. Roll the trackball to place the cursor where you want to inscribe a mark and
then push the left button to inscribe the mark. (You can see the range and
bearing to the cursor location by monitoring the mark range and bearing
indication just below the MARK box.)
To continue inscribing the same mark, repeat step 8.
To enter a different mark, push the right button when the guidance box reads
"MARK / EXIT" and then do steps 6-8. ("MAP MARK" should be chosen on the
MARK menu beforehand.)
To quit entering marks, push the right button when the guidance box reads
"MARK / EXIT".
.
5. VIDEO PLOTTER OPERATION
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