Simrad MX575D User Manual

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Technical specications | HS80/HS80A/MX575C/MX575D User Manual
Partial manual tune command ($GPMSK):
This command instructs the internal beacon receiver to tune to a specified frequency and
automatically select the correct MSK rate.
It has the following form:
$GPMSK,fff.f,M,,A,n<CR><LF
The internal SBX will reply with the following response:
$PCSI,ACK,GPMSK,fff.f,M,,A,n<CR><LF>
When this message is acknowledged by the internal beacon receiver, it will immediately tune
to the frequency specified and demodulate at the rate specified.
Field Description
fff.f Frequency in kHz (283.5 to 325)
M Designates manual frequency selection
ddd MSK bit rate (100 or 200 bps)
A Designates Automatic MSK bit rate selection
n
Period of output of performance status message, 0 to 100 seconds
($CRMSS)
Automatic beacon search command ($GPMSK,305):
This command initiates the beacon receiver to automatic mode of operation in which the
receiver operates without operator intervention, selecting the most appropriate beacon station.
This command has the following format:
$GPMSK,305,A,,A,,,<CR><LF>
The internal beacon receiver will reply with the following response:
$PCSI,ACK,GPMSK,,A,,A,n<CR><LF>
Field Description
A1 Automatic Frequency selection Mode
A2 Designates Automatic rate selection
null
The Smart GPS compass provides the above response to this variety of $GPMSK message,
and immediately tunes to the optimum beacon station in automatic mode, provided a
valid beacon almanac is present in receiver memory. Without a valid almanac, the beacon
receiver will perform a Global Search to identify candidate stations in the area, followed by the
acquisition phase of the initial search.
Beacon database search mode ($GPMSK,305):
This operating mode has been added to the MX575C/MX575D beacon receiver in order to
be compliant with the specification IEC 61108-4 for ship borne DGPS maritime radio beacon
receiver equipment.
The basic operation is outlined below.
1. The receiver will determine the 10 closest beacon stations after the GPS receiver has
calculated a valid position fix. The list can be accessed using the command $PCSI,3,2*.
2. The primary beacon channel tries to tune to the closest available station, using the frequency
and bit rate specified in the station database.
3. The background channel tunes to the frequency of the closest station using an alternate bit
rate.

Simrad MX575D Specifications

General

Brand	Simrad
Model	MX575D
Category	Marine GPS System
Language	English