Lowrance 3000mt 操作ガイド
7
GPS OPERATION
NOTE: A LGC-12S GPS module or an external GPS receiver with NMEA
output must be attached to this unit in order to use the position and navi-
gation features.
output must be attached to this unit in order to use the position and navi-
gation features.
WARNING!
Use this product only as an aid to navigation. A careful navigator never
relies on only one method to obtain position information.
relies on only one method to obtain position information.
CAUTION
This GPS receiver (like all GPS navigation equipment) will show the short-
est, most direct path to a waypoint. It provides navigation data to the
waypoint, regardless of obstructions. Therefore, the prudent navigator will
not only take advantage of all available navigation tools when travelling to
a waypoint, but will also visually check to make certain a clear, safe path
to the waypoint is always available.
est, most direct path to a waypoint. It provides navigation data to the
waypoint, regardless of obstructions. Therefore, the prudent navigator will
not only take advantage of all available navigation tools when travelling to
a waypoint, but will also visually check to make certain a clear, safe path
to the waypoint is always available.
INTRODUCTION TO GPS
The Global Positioning System (GPS) was developed by the United States
Department of Defense as a 24-hour a day, 365 days a year global navi-
gation system for the military. Civilian availability was added (but with less
accuracy) using the same satellites. Twenty-four satellites orbit the Earth.
Three of these satellites are spares, unused until needed. The rest virtu-
ally guarantee that at least four satellites are in view nearly anywhere on
Earth at all times.
The Global Positioning System (GPS) was developed by the United States
Department of Defense as a 24-hour a day, 365 days a year global navi-
gation system for the military. Civilian availability was added (but with less
accuracy) using the same satellites. Twenty-four satellites orbit the Earth.
Three of these satellites are spares, unused until needed. The rest virtu-
ally guarantee that at least four satellites are in view nearly anywhere on
Earth at all times.
The system requires three satellites in order to determine a position. This
is called a 2D fix. It takes four satellites to determine both position and
elevation (your height above sea level - also called altitude.) This is called
a 3D fix.
is called a 2D fix. It takes four satellites to determine both position and
elevation (your height above sea level - also called altitude.) This is called
a 3D fix.