FCC GMDSS study guide
FCC GMDSS · Work through your exam, one topic at a time.
The FCC GMDSS Radio Operator Certificate is the U.S. commercial operator credential associated with the Global Maritime Distress and Safety System, the international framework that governs maritime distress, urgency and safety communications at sea. The FCC GMDSS study guide has 6 sections and about 2,863 words.
01Distress, Urgency and Safety Communications Procedures
The Distress, Urgency and Safety Communications Procedures domain asks you to choose the correct priority, message format and frequency for an emergency, and to control or relay traffic without interfering with other stations. Most missed questions come down to one decision: is there grave and imminent danger right now, or only a safety concern?
532 words, about 3 min02GMDSS System Architecture and Sea Area Requirements
This domain tests the four sea areas, the functional requirements GMDSS satisfies, and the minimum equipment a given ship must carry for the area it sails. A1 - within radiotelephone coverage of at least one VHF coast station offering continuous DSC alerting (normally about 20–30 nm, further where a coast station extends it).
478 words, about 2 min03DSC (Digital Selective Calling) Operation
DSC Operation tests your command of digital calling: formats, MMSI addressing, the distress alert sequence, acknowledgments, and the discipline that keeps Ch 70 and the DSC distress frequencies clean. DSC formats are distress, all ships, individual, group and geographic area; categories are distress, urgency, safety and routine.
509 words, about 3 min04Satellite Communications (Inmarsat) and MSI Reception
This domain tests the satellite side of GMDSS - what each Inmarsat service does, how a distress alert reaches an RCC, and how maritime safety information is received in each sea area. Inmarsat operates geostationary satellites over four ocean regions (Atlantic East, Atlantic West, Indian, Pacific), covering about 70°N to 70°S - the A3 band.
443 words, about 2 min05Radiotelephony and NBDP / Telex Procedures
This domain tests the spoken and printed sides of GMDSS: voice discipline on the distress frequencies, and the narrow-band direct-printing conventions that carry distress, urgent and MSI traffic where voice is unusable. Use the ITU phonetic alphabet (Alfa, Bravo, Charlie) and standard prowords: THIS IS, OVER, OUT, ROGER, SAY AGAIN, I SPELL, WAIT, CORRECTION.
434 words, about 2 min06FCC Rules, Licensing and Radio Regulations
This domain tests the legal frame around GMDSS: who may operate, what the station needs, what is prohibited, and which instruments apply. The FCC regulates maritime radio under 47 CFR Part 80 (Subpart W covers GMDSS); internationally the ITU Radio Regulations and SOLAS Chapter IV apply.
467 words, about 2 min