Which statement best describes how to verify that an Inmarsat-C terminal is operational?

• A. Compose and send a brief message to your own Inmarsat-C terminal
• B. Request a coast station diagnostic
• C. Run a full satellite diagnostic
• D. Use a loopback test

Answer: (A)

To verify an Inmarsat-C terminal is operating, you test the ability to originate and deliver a message through the satellite network by sending a brief message to your own terminal. If you can compose and transmit a short message and receive it at the same terminal, you’ve demonstrated that the transmitter, path to the satellite, network routing, and the receiver are functioning. This practical, end-to-end check confirms the terminal can actively participate in the Inmarsat-C system.

Other options aren’t as useful for a quick functional check: a coast station diagnostic tests the ground station rather than your own unit; a full satellite diagnostic checks the satellite itself, which you can’t directly verify from your ship; a loopback test isn’t a standard means to verify Inmarsat-C operation since it wouldn’t reflect end-to-end operation over the satellite network.