The first mode in a tiered marine Emcomm system known as Global Maritime Distress and Safety System - Wikipedia or GMDSS. You may know from the RYA, as even leisure craft in coastal waters require for some form of vhf comms & a basic qualification (read license as it requires responsible use). VHF is your primary form of communication within sea area A1( both digital or DSC & radiotelephony or voice), but areas A2 & A3 further from land require MF, HF and satellite technology. Without going into too much detail larger & commercial vessels have a legal requirement for GMDSS, however other vessels can opt in. Back to VHF & its many uses from Distress, ship to ship/shore, Port Authority, Harbour Master, marina & MSI (Marine Safety Information). Remember this is line of site communication albeit up to 60 nautical miles, if you must 1 nautical mile is 1.15 land miles.
Intended use, I started with a handheld for personal carry for both leisure diving and SAR work. A basic marine VHF course, over 2 days in my case can be found through https://www.rya.org.uk or by looking online. The course will cover DSC https://en.wikipedia.org/wiki/Digital_selective_calling. Hopefully you will pass & can apply for your Ofcom license & MMSI ( Maritime Mobile Service Identity). The MMSI is the vital part of the service and Identifies the user, vessel, aircraft or coast station.
Although I’m not covering SOLAS (Safety of Life at Sea), GMDSS for sea areas A2,3, & 4 require either Long Range or General operators licenses with respect to MF, HF and satellite communications use. There are of course voluntary fitted vessels should the need exist for longer range comms. Naturally these courses & exams are studied in more depth. These vessels still carry VHF capability as part of that tiered system.
The phrase ‘Use it or lose it’ applies here. Practice makes perfect & gives you confidence in use. Regular maintenance & practice means it’s ready for use when you need it.
My own MMSI for handheld
When I first did my VHF course I needed it for a handheld, but it became a useful personal tool even if ours or other vessels had radios. It was class D DSC on me, simple digital automation of a distress signal. Well kept & always on you…Nuff said.
Doing the course for the license
Proved to be more fun than you may first think. A little study beforehand from a reference book calms the exam nerves, but the course will put you in good stead. Taking a group of guys, who’d just joined the SAR team, became a legendary tale, my advice crash the course in a group.
Continued personal development, bet you thought I meant something else. I went on to study for the LRC and will probably carry on to the GOC. Yes the courses are more expensive & you have to do them for the exam. Work meant that I would have to do the courses, but the books are out there to read for reference. We have always worked to the maxim of at least being consciously incompetent, rather than unconsciously !