Subelement C: Satellite Systems— Topic :
Question 30C6
Element 9 (GMDSS Maintainer)What error message may be displayed if a connection to the Inmarsat Mobile Packet Data Service (MPDS) network fails?
Explanation
Inmarsat terminals provide specific hexadecimal error codes to inform users about connection issues. When a terminal fails to establish a connection to the Mobile Packet Data Service (MPDS) network because it has not successfully registered, the system displays "00F0h" or "00F1h." Registration is a fundamental step in satellite communication, signifying that the terminal has been authenticated and recognized by the network, allowing it to access services. Without successful registration, no data connection can be established.
Options A, B, and C describe different, incorrect, or non-standard error codes and formats for this particular failure. "ECM 0071" or "77F0h/77F1h" are not the correct indicators for a terminal not being registered to the Inmarsat MPDS network. Option B also uses "ECM" and the reason "failure to transmit" is a consequence, but "not registered" is the specific initial cause indicated by "00F0h/00F1h".
Related Questions
30C4 What condition can indicate a communication failure between the second receiver (RX2) and the Antenna Control Unit (ACU) in an Inmarsat Fleet 77 terminal?30C5 Which of the following devices can cause interference to Fleet 77/55 systems?31C1 An Inmarsat-C terminal shows a “No Receive Signal” alarm. There is no voltage on the antenna center pin. What is the most likely cause?31C2 An Inmarsat-C terminal will not “LOG IN”. A test antenna cable with a new ADE attached in view of the satellite allows the terminal to “LOG IN”. What steps would you take?31C3 An Inmarsat-C terminal will not “LOG IN” and shows an “Antenna not connected” alarm. What action would you take?