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Tracker500/500i User Manual
15.0 Chart Datums
GPS derived positions are based on a worldwide reference (datum) known as WGS 1984.
Many charts are based on datums other than WGS 1984. This results in an offset between
a Lat/Lon plotted on the chart and the same Lat/Lon plotted on the Tracker500/500i. To
match the Tracker500/500i with your chart you must enter the datum specified on the chart.
See section 14.0 Setup for details on how to select a chart datum. Once your local datum
has been entered, all latitudes and longitudes, including waypoints, will match the chart.
Note: When using a number of charts with different datums it is important
to ensure that you change the datum to match the chart currently being
used. If the destination waypoint is on a different chart, be sure to
change to that chart’s datum before entering the latitude and longitude of
the destination waypoint.
Alternatively, you can manually enter a lat/lon offset value to bring the displayed lat/lon
values in line with the chart you are using. See the Setup screen for details on how to enter
a lat/lon offset.
The lat/lon offset function is typically used to match the Tracker500/500i
with older charts where an island may have a large position error, but all points around the
island have the same error.
ADINAN
Adindan
ADI-M
Ethiopia, Sudan
AFGOOYE
AFGOOYE
AFG
Somalia
AINELABD 70
AIN EL ABD 1970
AIN-A
Bahrain Island
AMRICN SAMOA
American Samoa 1962
AMA
American Samoa Islands
ANNA 1 AST65
Anna 1 Astro 1965
ANO
Cocos Islands
ANTIGUA
Antigua
AIA
Leeward Islands
ARC 1950
ARC 1950
ARF-M
Botswana, Lesotho, Malawi, Swaziland, Zaire,
Zambia, Zimbabwe
ARC 1960
ARC 1960
ARS-M
Kenya, Tanzania
ASCN IS 1958
Ascension Island 1958
ASC
Atlantic Ocean
ASTRO BCN”E”
Astro Beacon E
ATF
Iwo Jima
ASTRODOS71/4
Astro DOS 71/4
SHB
St. Helena Island
ASTR STN1952
Astronomic Station 1952
ASQ
Marcus Island
AUST.GEO1966
Australian Geodetic 1966
AUA
Australia and Tasmania
AUST.GEO1984
Australian Geodetic 1984
AUG
Australia and Tasmania
AUST.GEO1984
Ayabelle Lighthouse
PHA
Djibouti
BELLEVUE
Bellevue (IGN)
IBE
Efate & Erromango Islands (Vanuatu)
BERMUDA 1957
Bermuda 1957
BER
Bermuda Islands
BOGATA
Bogota Observatory
BOO
Colombia
CAMPO INCH
Campo Inchauspe
CAI
Argentina
CANTON AST66
Canton Island 1966
CAO
Phoenix Islands
CAPE CANAV
Cape Canaveral
CAC
Florida, Bahamas
CAPE
Cape Province
CAP
South Africa
CARTHAGE
Carthage
CGE
Tunisia
CHATHAM 1971
Chatham 1971
CHI
New Zealand
CHUA ASTRO
Chua Astro
CHU
Paraguay
Tracker
Datum name
Datum
Locality
abbreviation
code
Tanslation of Locality in the datum
table is optional but please do not
translate anything else in the table.