Which functions may the holder of a GMDSS Radio Operator License NOT perform on the Inmarsat-C equipment?

The correct response highlights a key aspect of the roles and responsibilities associated with the operation of Inmarsat-C equipment under the GMDSS framework. While the holder of a GMDSS Radio Operator License is permitted to maintain the equipment and perform basic operational tasks such as logging on and off, handling traffic, and entering position data, they are not authorized to adjust intricate technical specifications like the transmitter Effective Isotropic Radiated Power (EIRP).

This restriction on optimizing performance by adjusting EIRP is in place because such adjustments typically require specialized technical knowledge and could potentially interfere with the system's proper functioning or with other communications. Only certified technicians or engineers with the requisite training and qualifications should perform maintenance and adjustments that affect the equipment's transmission characteristics. The integrity and performance of communication systems in maritime environments rely heavily on adhering to strict operational protocols, making it essential that licensed operators not take on tasks that fall outside their training and authority.