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GX2200
9.6 GROUP CALL
This feature allows the user to contact a group of specific vessels (e.g.
members of a yacht club) using DSC radios with group call function to auto-
matically switch to a desired channel for voice communications. This func-
tion is very useful for yacht clubs and vessels traveling together that want
to collectively make announcements on a predetermined channel. Up to 32
group MMSIs may be programmed.
9.6.1 Setting up a Group Call
For this function to operate, the same group MMSI (Maritime Mobile Service
Identity Number) must be programmed into all the DSC VHF radios within
the group of vessels that will be using this feature. To understand Group
MMSI programming, first a ship MMSI has to be understood.
Ship MMSI
:
The first three digits called MID (Mobile Identity Group) of a ship
MMSI denote the country the ship registered for an MMSI. The last 6 digits
are specific to the ships ID.
Ship MMSI Example
: If your MMSI is “366123456”, “366” is MID which
denote the country and “123456” is your ships MMSI.
Group MMSI
:
Group MMSI numbers are not assigned by the FCC or other organiza-
tions licensed to assign ship MMSI numbers.
The first digit of a group MMSI is always set to “0” by International rules.
All Standard Horizon radios are preset so when programming a group
MMSI the first digit is set to “0”.
The USCG recommends programming the MID of a ship MMSI into the
Second, Third and Fourth digits of the group MMSI as it denotes the area
the ship is located in.
The last 5 digits are decided upon by persons in the group. This is an
important step as all radios in the group must contain the same group
MMSI so they can be contacted by each other. There is a chance that
another group of vessels may program in the same group MMSI. If this
happens, simply change one or more of the last 5 digits of the group
MMSI.
