Lowrance LMS-350A, Инструкция по установке и эксплуатации

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This page shows the station ID
number, its frequency and bit
rate, the "health" of the station
(0 = best, 5 = worst), signal
strength (the higher the num-
ber, the better), and the signal-
to-noise ratio (SNR). The high-
er the SNR number, the better.
The lower half of the screen
shows statistics for each of the
receiver's five channels. This
includes the satellite number
(PRN), its status (STAT), the User Differential Range Error (UDRE), Time
status (TIME), and if SA (Selective Availablity) is on or off. The UDRE is
the range error from your position to the satellite. If there is an "OK" in this
field, then the range error to that satellite is 8 meters or less 68 percent of
the time.
For more information, read your beacon receiver's manual.
The LMS-350A can display navigation information in magnetic or true.
When it’s turned on for the first time magnetic is used. To switch to true,
press the MENU key while a GPS screen is displayed. Next, press the key
next to the “Change GPS Settings” label. Now press the key next to the
“Select Units of Measure” label. Now simply press the key next to the
“Bearing” label. This moves the black box from “MAG” to “TRU.” Press the
key next to the “Exit” label when you’re finished.
TRUE and MAGNETIC POSITION
True and magnetic north are not the same. True north is the top of the
world. It’s where all lines of longitude converge. Magnetic north is the
location our compasses point. It lies several hundred miles to the south of
true north, at a location in Canada.
Charts are usually laid out according to a Mercator projection that uses
true north. If you plot a course on a chart using the Mercator projection,
you’ll either have to convert magnetic to true or use true readings.