Definition On Terms - JRC FF50 Instruction Manual

Definition on Terms

2D (two-dimentional) ..... Position fixing using satellites and height information.
3D (three-dimensional) ... Position fixing using satellite information only from
Anchor alarm .................. An alarm indicating that the vessel has deviated more
Arrival alarm ................... An alarm indicating that the vessel has come within
Automatic sequencing
mode .............................. Function that automatically steps from one waypoint
Bow ................................ The front of a vessel (nautical term).
Cavitation ....................... Air bubbles in the water which affect the echo level
CDI ................................ Course Deviation Indicator. Information that indi-
Chart speed ..................... The rate at which echoes scroll across the display. The
Default value .................. Factory set value
DGPS ............................. The process of correcting the inaccuracies of GPS
Fairing block ................... A block used when mounting a thru-hull transducer,
GPS satellite ................... GPS stands for "Global Positioning System." Several
HDOP ........................... Indicates the accuracy of Horizontal position fixing.
Hull ................................ The exterior surface of a ship.
four or more satellites
than the set distance from a waypoint.
the set distance of a waypoint.
to the next when the arrival perpendicular point has
been detected.
measured by a transducer, normally caused by mount-
ing the transducer at an incorrect angle or location.
cates the extent you have strayed from the route
intended and the direction to steer.
higher the chart speed, the quicker response of the
picture. The slower the chart speed, the more history
the picture displays.
position data from GPS satellites by receiving a beacon
Differential Signal from a base station whose exact
position is known. And which transmits correction
data for the GPS satellites it receives.
for shimming the transducer to align it on a perfect
horizontal plane versus the rise of the hull.
satellites launched by the US Department of Defense
to establish a military navigational aid system.
The smaller the number shows the more accurate the
position fixing.
When the satellites are grouped together, HDOP
increases and position fixing accuracy is poorer when
the satellites are Farther apart, HDOP decreases and
position fixing accuracy is enhanced.
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