Boating and Sailing.pdf - Moja ladja

Chapter 13: Tools and Tricks of Navigation
Why should you spend more for either system since getting within 20 meters is often
enough? First, if you’re an avid bottom fisherman, you’ll find that being dead on the reef
or ledge is often required for good action. Second, if you have to depend on your GPS to
put you on the right side of a channel marker on a dark and foggy night, that extra accuracy
can be hugely important. And for those who race sailboats, where speed differences
of less than 1 mph can sometimes mean winning
or losing, the extra accuracy of the speed
indications of these units make them well worth
the cost. Currently cost of DGPS receivers,
which plug in to DGPS-ready units, is $300 to
$500, and WAAS systems, complete within one
box, are about the same.
Basic Global Positioning Systems are becoming
more affordable each year, and some are now
available in console versions for around $200.
Unlike radios, portable or handheld GPS units are
just as useful as fixed units and just as accurate.
They burn batteries rapidly, but converters allow
you to hook them to the boat batteries. Some cost
as little as $100, or less than a tenth of what the
first units to hit the civilian market went for!
Do-It-All Chart Plotters
The ultimate inshore navigational tool is a chart plotter with a built-in GPS. On the
screen, you zoom in on a navigational chart of the area you’re cruising, usually via
postage-stamp–sized chart cards that insert into the machine.
The GPS then positions your boat on the chart, and you can see your progress as it tracks
your course. Even the buoys and other navigational aids are shown, and you can track
your boat on-screen as it zooms past Marker 1 and heads for home.
Recent models allow you to simply place a cursor on a distant location, click a couple of
buttons, and the machine plots a latitude/longitude course to that location.
You can insert as many waypoints, locations along the way where you might want to check
your navigation or simply stop for a picnic, as you like. You can even get a graphic tide
chart of the area as part of the display.
Simpler, hand-held chart plotter/GPS units have fewer bells and whistles, but some of
them also offer charts on-screen. Battery life can be a problem for some, but all offer
12-volt battery hook-ups.
189
Boat Bytes
Do you really need electronic
navigation gear? If
you do your boating on
inland lakes and rivers,
you’ll probably never miss
it, although it could be a help in
finding your favorite offshore fishing
spots at times. On the other
hand, if you operate on the
Great Lakes or the coasts, out of
sight of land, electronic positioning
equipment is a must. It’s by
far the most reliable and easiest
way of keeping track of where
you are.