NorthStar 6000i, Быстрый старт и справочное руководство

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Reference section 10 — Setup
Changing your receiver settings Reference Manual Revision D
steadiest readings and highest accuracy,
such as when you want to trawl at a
certain optimum speed.
Choosing beacon frequency and baud
rate (optional equipment)
Differential corrections are invaluable for
navigating in narrow or congested areas,
such as ports and waterways, or whenever
you require extreme accuracy in order to
locate a particular spot.
WAAS is one source of accurate correc-
tions received directly from satellites. If
you need an alternate source, you can
interface your
6000i with an optional
external Northstar beacon receiver. A
beacon receiver takes corrections broad-
cast by shore-based marine radiobeacons
situated along most of the U.S. coastline
and uses those corrections to further
enhance the accuracy of GPS. Beacon
frequencies are automatically selected as
you move from one differential coverage
area to another, or as weather conditions
change. The receiver constantly evaluates
the quality of the radiobeacon signals, and
selects the best station.
Automatic mode
Automatic differential mode can normally
be used at all times. One receiver channel
tracks the best available differential signal
and sends DGPS corrections to the 6000i’s
GPS receiver. Another channel continu-
ously scans the entire differential
frequency band (283.5 to 325kHz), evalu-
ating available DGPS signals.
If the signal that’s received and monitored
by Channel 1 degrades for any reason
(such as bad weather between your vessel
and the transmitter), the 6000i tries to
select a better frequency from the direc-
tory it has compiled. This function allows it
to switch to the best differential signal
before your GPS accuracy is affected.
Manual mode
Although the need is rare, you can
manually override the beacon receiver’s
automatic mode at any time. In manual
mode, the beacon receiver uses only the
selected station.
To manually choose a differential station,
you must select the frequency of the
desired station:
1. On the
RECEIVER OPTIONS
screen,
highlight the Beacon Frequency option
and press
Edit
.
2. Change the settings from AUTO to MAN-
UAL. A differential transmitter frequency
appears to the right of the word MANUAL.
3. Press the cursor pad to the right to high-
light the digits you want to change. Enter