NorthStar 958, Руководство оператора

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Page 66 958 Operator’s Manual, Rev. A
Chapter 5 - Determining Your Position
Using loran
This section explains how you can use the 958 to navigate
using displayed loran coordinates if the 958 is connected to an
loran receiver (such as the Northstar 800). If you don’t plan to
use loran, you can skip this section.
Selecting and
displaying loran
To display loran time differences (TDs) from a connected loran
receiver:
1. Press the
STAR
key to display the
OPTIONS/SERVICE
INFO
screen.
2. Press the
NAVIGATION OPTIONS
menu key, then select
the
NAVIGATION SOURCE
field.
3. Press the
EDIT
menu key, then press the
CURSOR PAD
to
display
EXTERNAL LRN
as the position source.
4. Press the
ENTER
key, then press the
RETURN
menu key.
5. Press the
CHART
key to display the
GPS POSITION
screen.
6. Press the
CHECK LORAN
key to display the
LORAN POSI-
TION
screen.
TOO FEW CORRECTIONS
DGPS is off because not enough satellites with corrections are
available.
POOR BCN DOP
DGPS is off because the satellites with corrections have poor
geometry (DOP is an acronym for Dilution Of Precision).
OLD CORRECTIONS
DGPS is on, but the current corrections are older than the timeout
you’ve set in the receiver options (see ”Choosing a DGPS correc-
tions time-out” starting on page 176).
DGPS IN USE/OK
DGPS is on and the corrections are current.
UNKNOWN
An unknown status code has been received from the GPS receiver.
Table 4: DGPS status messages (continued)
DGPS message Meaning