NorthStar 941X Reference Manual page 129

NMEA 0183
lat/lon precision
Rev. D
the listener device is expecting. Check the listener device's instruction
manual to determine which "talker ID" codes it will respond to.
Use the EDIT menu key, then scroll through the three choices using the
up/down cursor arrow keys to make your choice. Press ENTER when
done.
The interfaced equipment will then receive the 0183 data in the correct
nav-source format.
(PORT 1 / PORT 2 SETUP) (PORT 1 / PORT 2 SETUP)
(PORT 1 / PORT 2 SETUP) (PORT 1 / PORT 2 SETUP)
For added versatility in communicating with a variety of other devices,
you can control the level of precision of the 0183 position information as
it's output by the 941X.
Using the EDIT menu key and the up/down cursor keys, you'll see the
display change from:
XX.XX ' (lat/lon precision to two decimal places / hundredths of
minutes / or 60 feet) to
XX.XXX ' (three decimal places / thousandths of minutes / or 6
feet), to
XX.XXXX ' (four decimal places / ten-thousands of minutes / or
roughly ½ foot).
The factory default is .XXX .XXX .XXX (thousandths of minutes). .XXX
Precision output to three or four decimal places does not mean
that your 941X navigates with such accuracy, unless it is using
DGPS. Position information can be output and displayed to
four decimal places, but your actual ability to navigate to such
a precise point is limited by the accuracy of the Loran and GPS
systems (see "Comparing GPS and Loran," on page 5). There-
fore, specifying more decimal places in the data output does
not result in greater navigating accuracy.
The choice you make is dependent upon the equipment to which you are
outputting NMEA data. The 941X conforms to the NMEA version 2.10
standard, but is also compatible with version 1.50. Equipment typically
benefiting the most from three and four decimal places of precision are
electronic and pen plotting devices. However, most all older devices de-
signed to operate with the original 0183, and other formats, can only
9 — Installation and Interfacing 9 — Installation and Interfacing
9 — 9 — Installation and Interfacing Installation and Interfacing
NOTE
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