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Maritime Mobile
Service Identity (MMSI)
Nothing Comes Close to a Cobra
®
9
8 English
Digital Selective Calling (DSC)
The vessel Corsair calling the vessel Vagabond:
Corsair:
“Vagabond, this is Corsair (station license number call sign) .”
Vagabond:
“Corsair, this is Vagabond . Over .”
Corsair:
“Vagabond go to working Channel 68 . Over .”
Both parties switch over to the agreed upon working channel . . . .
Corsair:
“Vagabond I need to talk to you about . . . Over .”
Vagabond:
“Corsair in answer to your question about . . . Over .”
Corsair:
“Vagabond, thanks for the information about . . . (call sign and
out
) .”
After each transmission, say “OVER” and release the microphone
Push to Talk
(PTT)
button . This confirms that the transmission has ended . When all communication with
the other vessel is totally completed, end the message by stating your call sign and
the word “OUT .” Remember, it is not necessary to state your call sign with each
transmission, only at the beginning and end of the message .
NOTE
For best sound quality at the shore station or other vessel receiving your call, hold
the microphone/speaker at least 2 in . (51 mm) from your mouth and
slightly off to one (1) side . Speak in a normal tone of voice .
Digital Selective Calling (DSC)
•
Digital selective calling is a semi-automated system for establishing a radio
call . It has been designed by the International Maritime Organization (IMO)
as an international standard for VHF, MF, and HF calls and is part of the
Global Maritime Distress and Safety System (GMDSS) .
DSC will eventually replace aural (listening) watches on distress frequencies
and will be used to announce routine and urgent maritime safety information
broadcasts . Until DSC is fully implemented, it is still necessary to maintain a listening
watch on Channel 16 .
The DSC system allows mariners to instantly send a distress call with GPS
position coordinates (requires a GPS receiver to be connected to the radio)
to the Coast Guard and other vessels within range of the transmission .
DSC also allows mariners to initiate and receive distress, urgent, safety,
routine, position request, position send, and group calls between vessels
equipped with DSC capable radios .
VHF Marine Radio Protocols
VHF Marine Radio Protocols
Maritime Mobile Service Identity (MMSI)
•
The MMSI Number Is Available In The U.S.A. From Any Of Two (2) Sources:
n
U .S . Power Squadron www .usps .org
n
BoatU .S .: 1-800-563-1536 – www .boatus .com/mmsi
NOTE
The above references are for recreational vessels only . Commercial vessels
should contact the FCC .
An MMSI is a nine (9) digit number used on a marine radio capable of using digital
selective calling (DSC) . It is used to selectively call other vessels or shore stations and
is similar to a telephone number .
For your CobraMarine
™
radio to operate in the
DSC
mode, you must enter your
maritime mobile service identity (MMSI) number . See page 41 for instructions
on how to enter it .
In Canada, Contact:
n
Industry Canada Spectrum Management Office (only available on the Internet):
www .ic .gc .ca and search for “MMSI” .
To Obtain An MMSI Number Outside The U.S.A.:
Users can obtain an MMSI from their country’s telecommunications authority
or ship registry . This may involve amending or obtaining a ship station license .
WARNING
This equipment is designed to generate a digital maritime distress and
safety signal to facilitate search and rescue . To be effective as a safety
device, this equipment must be used only within communication range
of a shore-based VHF marine channel to distress and safety watch system .
The range of the signal may vary, but under normal conditions should be
approximately 20 nautical miles .
For Example
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