Furuno GD-3300, GP-3300 2.5 Track Plotting Interval

2-6
2.5 Track Plotting Interval
The plot interval determines how the track will be reconstructed on
the display and track storage time. The equipment has two plot inter-
vals, plot interval 1 and plot interval 2, which you can set as desired.
You can select which one to use by the [PLOT INTVL] key. This
section shows you how to preset the plot intervals, on the INITIAL
SETTINGS menu.
How the track is drawn
The “quality” of the track displayed largely depends on the plot inter-
val setting, smoothing rate, etc. In drawing the track, first the ship’s
position fed from the navigation receiver is stored into this unit’s
memory at an interval of time or distance selected by the operator.
This interval of time or distance is called the “Plot Interval” and it is
selected considering the ship’s speed, the chart scale, etc. If a shorter
interval is selected, a reconstructed course line is provided with bet-
ter accuracy, but total storage time of the track is reduced.
Plot interval and track reconstruction
Obviously there is a trade off between smooth reconstruction of the
track and plot storage time: The shorter the interval the smoother the
reconstruction but storage time is reduced. Figure 2-10 compares plot
interval and track reconstruction.
ACTUAL
TRACK DISPLAYED TRACK
Figure 2-10 Plot interval and track reconstruction
Plot interval by time or distance
The plot interval can be selected by “Time” (00 sec. to 99.59 min.) or
“Distance” (00 nm to 9.99 nm). If the plot interval is selected by
distance, you will not use up memory points when the boat is an-
chored.