Furuno FAR-3210 Operator's Manual page 377

4. For [Manual], manually enter position, enter a comment if required, then click the
[Record] button.
Enter position manually.
The position event mark appears at the manual input position. The position is re-
corded to the [Voyage] log.
Time of entry
5. For [LOP], see the description below.
Position fixes defined by Line of Position (LOP)
A plotted line on which a vessel is located, determined by observation or measure-
ment of the range or bearing to an aid to navigation or other charted element. Two or
more simultaneous observations can be combined to produce an estimate of the
ship's current position. If the position is based on only two observations, it is an "esti-
mated position" (EP); otherwise it is called a fix. A maximum of 6 observations can be
entered to obtain a fix.
Basic operation: Coordinates of the aid to navigation can be entered into dialog box-
es or they can be selected graphically on the chart. Click on a charted object (beacon,
light, buoy etc.). Description of the object appears above coordinate boxes.
Default values for bearing and range are approximated from ship's current position in-
formation. The time of observation is stopped when the object is selected (or when the
[Add] button is clicked). Click the [Add] box to include the observation in the fix com-
putation. The counter shows "new/1", at the input of the second observation. The word
"new" indicates that the observation currently displayed is not yet included in the fix
computation, and it appears as a dashed line or ring on the chart. The added obser-
vations can be edited or deleted after selecting them at the counter. When at least two
measurements are entered, the EP or fix is computed and the coordinates are shown
in the top part of the dialog.To show a position symbol on the chart, click the [Record]
button. In the case of an EP, the letters EP are shown on the right side of the coordi-
nates. If a valid position estimate cannot be obtained, a message is displayed under
the coordinates. This may happen, for example, if the lines / circles have multiple
crossings that are far apart, or if two lines are nearly parallel or don't intersect at all.
The accuracy limit (estimated standard error) is 1.0 NM. If the estimate is valid, the
[Record] box can be clicked to record the current position estimate in the [Voyage] log.
Discrepancy between LOP result and ship position is also recorded in the log (this in-
formation may be viewed by Info query on the position event symbol on the chart -
which is displayed if position event display is on in chart display settings).
1044
DGPS1
Navigator selected
Position event mark
19. RECORDING FUNCTIONS
Enter comment
here if required.
19-3