GMDSS-SRC-L1.3

MMSI and maritime identities

GMDSS-SRC-M1 · Radio fundamentals · GMDSS-SRC-M1-A How VHF works, what each channel is for, DSC and the identities behind it.

Every DSC set, AIS unit and modern beacon identifies itself by a **nine-digit number**. Knowing how MMSIs are built tells you at a glance whether a call comes from a **ship, a coast station, a group, an aircraft or a survivor's beacon**.

Independent study. xplor is not an accredited training provider and awards no certificate or Certificate of Competency. The SRC is awarded only after a course at an RYA-recognised centre and the RYA's written and practical exam, conducted on behalf of the MCA. AI-drafted content pending subject-matter-expert review.