Subelement C: DSC & Alpha-Numeric ID Systems— Topic :
Question 14C6
Element 7R (GMDSS-RO)Which of the following numbers indicates a ship station MMSI?
Explanation
A Maritime Mobile Service Identity (MMSI) is a unique 9-digit number assigned to stations in the maritime mobile service. For a ship station, the MMSI always begins with a three-digit Maritime Identification Digit (MID), which ranges from 201 to 799.
* **D) 623944326** is a 9-digit number starting with '623'. Since '623' falls within the 201-799 range, this indicates a ship station.
Let's look at why the others are incorrect:
* **A) 003372694** starts with '00'. This prefix designates a coast station.
* **B) 030356328** starts with '0'. A single '0' followed by an MID typically indicates a group call station (e.g., for a fleet) or other specialized stations like an aid to navigation (AtoN) or aircraft. It is not a standard ship station MMSI.
* **C) 3384672** is only 7 digits long. An MMSI must be 9 digits.
Related Questions
14C4 Which of the following numbers indicates a U.S. flag ship station?14C5 Which of the following MMSI numbers indicates a U.S. flag ship station?15C1 A DSC call is received from a station with a MMSI number of 003669991. What type of station made the call?15C2 A valid MMSI number for a DSC call to a specific group of vessels is:15C3 A MMSI 030346239 indicates what?