Understanding Electronic Charts - NorthStar 951X Operator's Manual

Understanding electronic charts

Chart boundary
Chart details
951/952 Operator's Manual Rev. B
distance across the chart, from edge to edge), along with either
your present SOG and COG, or the distance and bearing to
your waypoint, or your position coordinates.
You also can use the
get to the waypoint without needing to remain precisely on the designated
course line.
Navionics' electronic charts contain much of the information
from the original paper charts, although spot depth soundings,
some nav aids, and other data are missing from the electronic
version. When used with the proper caution, however, elec-
tronic charts can open up a new world of navigation accuracy
and simplicity.
Don't let yourself become overconfident when using electronic
charts. Always be cautious!
Each cartridge contains data from a number of paper charts.
The boundary line for each chart can be displayed on the
lines
CHART screen. Although the chart identification numbers
can't be displayed, the experienced mariner with local knowl-
edge may be able to identify the original chart sources by the
size and location of the boundary lines. Familiarity with chart
sources can help in identifying the features found on an elec-
tronic chart.
As you move from one chart to another, be aware that the
available detail levels may vary from chart to chart. If you
move from a highly-detailed chart to a less detailed one, you
may see a sudden change in the detail shown on the screen,
just as if you were changing from one paper chart to the next.
NOTE:
CHART
screen to steer by when your objective is to
CAUTION!
Chapter 4 - Using Charts
Page 43