Chapter 5 - Understanding Position Coordinates
Page 5-2
961 Operations and Reference Manual Rev. D
Using GPS to determine position
The 961 uses a high-performance GPS receiver as its primary
source of position data. Calculated directly from the received
satellite data are your present position in lat/lon coordinates,
time of day and date, speed-over-ground (SOG) and
course-over-ground (COG), and an estimate of the 961’s accu-
racy.
Lat/lon coordinates
On the
CHART
screen
INFO BAR
s, the 961 displays lat/lon as
degrees, minutes, and thousandths of minutes. To display this
data, press the
INFO
key several times. After pressing the first
INFO
key, a second
INFO
key is displayed, letting you display
additional data on the second
INFO BAR
.
SOG and COG
You can display SOG and COG in the
INFO BAR
on the
CHART
screen, or on the
3-D STEER
screen or numeric
STEER
screen.
To display SOG and COG on either the
STEER
or
3-D STEER
screens, press the
STEER
key once or twice.
SOG and COG readings result from ongoing measurements
derived from the satellite signals; GPS speed is updated every
second. You can set the 961 to display its SOG and COG read-
ings more smoothly by setting the GPS speed averaging value
up to 10 seconds. Increasing this averaging time, however,
may reduce overall reaction time. For details about GPS speed
averaging value, see ”Changing GPS speed averaging value”
starting on page 14-5.
Loran-C TDs
The 961 also calculates Loran-C TDs from the GPS coordi-
nates, and displays them on the
CHART
-screen
INFO BAR
s. For
details, see ”Viewing loran TDs” starting on page 5-9.
GPS receiver status
summary
To display information about the GPS satellites, press the
STAR
key to display the
SERVICE MENU
screen, then press
the
GPS STATUS
key. The 961 displays the
GPS SATELLITE
STATUS
screen, showing the status of the GPS receiver. This
screen also displays the status of the DPGS receiver, if installed
(961XD).
Summary of Contents for 961X
Page 1: ...961 961 GPS Chart Navigator Operations and Reference Manual P N GM1700 Revision D X XD ...
Page 8: ...Page viii 961 Operations and Reference Manual Rev D ...
Page 10: ...Page x 961 Operations and Reference Manual Rev D ...
Page 58: ...Chapter 2 Introducing the 961 Page 2 16 961 Operations and Reference Manual Rev D ...
Page 172: ...Chapter 7 Creating Avoidance Points Page 7 16 961 Operations and Reference Manual Rev D ...
Page 198: ...Chapter 8 Creating Routes Page 8 26 961 Operations and Reference Manual Rev D ...
Page 262: ...Chapter 12 Alarms TideTrack and Currents Page 12 16 961 Operations and Reference Manual Rev D ...
Page 374: ...Index Page I 12 961 Operations and Reference Manual Rev D ...