Does anyone actually use DSC?

[BillKny]

Originally Posted by Dockhead

Here I will have to disagree with you, and I think if you will talk to any Coastguardsman you will be disabused of this notion. A DSC distress call sets off a loud alarm on all VHF sets within range and, crucially, gives your lat, long, name of vessel, MMSI, and nature of emergency to the Coastguard and everyone else, instantly. In a real emergency this can be crucially better than trying to read all that information off, possibly not being heard well, or something mistranscribed of misunderstood -- all while you're in some kind of disaster. And the DSC part of a Mayday call is not INSTEAD OF a the voice part, but in addition to. Please do use the red button, if you get into such a situation. Any SAR worker or Coastguardsman will tell you the same.

I hear you. However, I would point out that I was specifically talking about getting MY ATTENTION. If I hear a DSC distress alarm I push the ACK button (How does that work, again???) and then ignore it unless I hear something else on voice comms.

Also, never have I heard the USCG tell a boat in distress to "Push the red button," after an initial voice connection to transmit position data.

I do know that the times I have listened to the follow up on DSC distress alarms the USCG did not physically launch SAR assets to respond to the DSC alert. In the absence of collaborating information it was treated as a false alarm.

I have never heard a DSC broadcast distress alarm that actually was the result of an real distress situation. I am sure someday it will happen.

If I have ignorant crew on board who had no idea how to use a VHF, then the "Red Button" is certainly part of the safety briefing, but that is a vanishingly rare situation on my boat.

I sometimes sail in a lot of very busy and congested areas along the US east coast. I have never been in a place where CH16 was so busy that a hail was difficult to fit in. Very, very rarely CH16 can be tied up with a SAR event, but that is infrequent enough I don't worry about it.

For collision avoidance, I think there is a lot of benefit to the "party line" approach that goes with standard voice coms. I know I gain a LOT of situational awareness in congested areas listening to other ship's Bridge-to-Bridge coms and wouldn't want those to go private.

The first time I get an actual DSC call from a commercial or official vessel I'll start to pay attention to it. In the meantime, I treat it as a nerdy yachtie's toy.

By the way, I am not being intentionally insulting there. Nerdy yachties help keep out technology moving forward.

[rslifkin]

In my mind, in a real emergency, DSC distress call first, voice call second. That way if you have to bail or lose your ability to transmit fairly quickly, you've at least gotten the message and your position out there first.

[Tupaia]

Originally Posted by rslifkin

In my mind, in a real emergency, DSC distress call first, voice call second. That way if you have to bail or lose your ability to transmit fairly quickly, you've at least gotten the message and your position out there first.

Think all this is valid and shows the failings of the GMDSS system. If you are in a "non" technical underdeveloped country then you are mad to relay on DSC distress. The system was designed by "westerners" for use in "western" countries (and as is evident from postings here this has not been embraced by many). In remote locations you are far more likely to reach a boat close by calling Mayday on Ch16. Many countries do not even have rescue services some have rescue services on paper but no boats or boats that don't work.

[donradcliffe]

Originally Posted by Dockhead

You set the radio on the mother ship to respond automatically to position requests (you can set to respond to only one or a list of MMSI's or to anyone who calls). Otherwise position requests are answered only if someone on the mother ship confirms.



Then you ping the mother ship from the dink with a position request. You get lat, long, range and bearing. You use these are you like. Range and bearing is usually all you need; otherwise write down lat and long and plot or transfer to a nav app on whatever device you have with you.


From the mother ship, received position reports are plotted automatically on the plotter.

Nice in theory, but the reality is that every radio manufacturer has a different set of menus which require instructions buried in the 15 pages of the manual that deals with DSC. To date, I have never seen one that can provide for automatic responses to position requests.

[Dockhead]

Originally Posted by Tupaia

Think all this is valid and shows the failings of the GMDSS system. If you are in a "non" technical underdeveloped country then you are mad to relay on DSC distress. The system was designed by "westerners" for use in "western" countries (and as is evident from postings here this has not been embraced by many). In remote locations you are far more likely to reach a boat close by calling Mayday on Ch16. Many countries do not even have rescue services some have rescue services on paper but no boats or boats that don't work.

Again, it's not either/or. GMDSS protocol requires you to send the DSC distress signal AND call Mayday in phone on 16.

And don't underestimate the technical abilities of coast guards in third world countries. I would guess that approximately all of them know very well how to receive and log the data from a DSC distress signal. Even if they don't have vessels to send out for you, their job is to coordinate rescue, and they will almost certainly have a higher and better antenna than you have and better overview of what vessel could get to you most easily.

It would be very bad practice to skip the red button part of the protocol.

[George_SD]

Never used it.

Doing it via radio's minimalistic controls and menu systems on a tiny screen is a PIA. As others mentioned - it is a good idea with poor implementation. I think if they did it with a rotary dial like old phones it would be used more often than the menu-up-down-left-right-select nonsense.

Many engineers are just terrible at UI/UX because they don't need it to be intuitive. Their level of familiarity with the original idea, what it does and how it could work skews their view of usability vs someone who has never seen it or may need to use it once every couple of months.


Regular use of DSC by occasional sailor has two hurdles to overcome: long and convoluted menu + terrible "dialing" process. Both are usability issues.

Menu is easy to fix, just don't ask an engineer to do it.

Dialing can be simplified with rotating knob with push to select that is used to select numbers on a two row display where options are shown on one line and selection added on the other would have solved part of the problem. Similar to how many cars these days have rotating dial and push to select when entering street address or house number.

[Dockhead]

Originally Posted by donradcliffe

Nice in theory, but the reality is that every radio manufacturer has a different set of menus which require instructions buried in the 15 pages of the manual that deals with DSC. To date, I have never seen one that can provide for automatic responses to position requests.

Icom M604 does:



And so can my handheld:





I don't believe I've seen a DSC radio where you CANNOT set up an automatic response to a position request. It's even the DEFAULT condition of my handheld.

[rslifkin]

Originally Posted by donradcliffe

To date, I have never seen one that can provide for automatic responses to position requests.

My Standard Horizon GX1850s can do it.

[sail sfbay]

A VHF-DSC radio must include an integrated GPS OR be properly interfaced with the boat’s GPS to give position data......something the Coast Guard estimates 8 out of 10 boaters fail to do—and it must be registered with a Maritime Mobile Service Identity (MMSI) number. I have vhf radios on my sailboat and powerboat, each with GPS and integrated AIS receiver, and backup vhf radio with DSC on each boat.

You might consider additional safety devises to alert search and rescue in the event of an emergency on your boat such as Emergency Position Indicating Radio Beacon (EPIRB) with internal GPS, Personal locator beacon (PLB) and wearable Man Overboard (MOB) safety devices.

[Tupaia]

Originally Posted by Dockhead

And don't underestimate the technical abilities of coast guards in third world countries. I would guess that approximately all of them know very well how to receive and log the data from a DSC distress signal. Even if they don't have vessels to send out for you, their job is to coordinate rescue, and they will almost certainly have a higher and better antenna than you have and better overview of what vessel could get to you most easily.

It would be very bad practice to skip the red button part of the protocol.

I listened to a distress situation in Fiji involving calls to the Navy. It took 25 mins to respond to repeated Mayday calls. They were unable to coordinate a rescue relaying on the boat in distress to handle the things. They were unable to comprehend the lat and long position had no idea how to plot this and the boat that was eventually sent out capsized and the crew were rescued by the boat in distress that was high and dry on the reef.


Totally agree with red button but don't relay on a response.

[Mike OReilly]

Originally Posted by donradcliffe
To date, I have never seen one that can provide for automatic responses to position requests.

Originally Posted by rslifkin

My Standard Horizon GX1850s can do it.

So does my SH GX2200 ... I've just never used it, except while testing the system.

[Bill_Giles]

I teach marine band radio for licences in the UK. DSC is included in the exam so I teach it. I know that in any other situation than Distress DSC is barely used. It is a shame that if our vhf radios were to be replaced as frequently as mobile phones the system would be much more widely used because it would have been made much more user friendly. It is useful if you cruise in company and the UK Coast Guard would like it if you called them on it.

Interestingly, we were called by the CG through DSC who had our MMSI through AIS to ask us to look out for red flares after some had reported seeing them near our position. (We did not see anything)

[Happ]

Originally Posted by BillKny

I know how DSC on a marine VHF works, it is set up on my radio, I have tested it.

With the exception of a few (always false alarm) DSC distress calls NEVER has anybody placed a DSC call to my radio.

NEVER have I placed a VHF DSC call to anybody else’s radio.

NEVER have I talked to anyone who has actually placed a DSC radio call, or received one.

NEVER have I been in a real world situation where I thought, “Gee, DSC would really help right here...”

Am I just not one of the cool people who hang with the “in” crowd? Or is this a VHF radio feature that has never received any actual user traction?

Is there a broad base of use in the commercial shipping world I have just never heard of?

It’s called AIS! Yes I use it every time I leave the dock. I was sailing back from Annapolis and a 40’ powerboat was going along at about 7 knots. I saw them on AIS hailed them and he altered course. AIS gives the boat’s name, speed and direction. Also how close you will come to other boats.

You need to know what you own and how to use it. A GPS does you no good if you don’t know how to use it.

[Dockhead]

Originally Posted by Bill_Giles

. . . and the UK Coast Guard would like it if you called them on it.

Interestingly, we were called by the CG through DSC who had our MMSI through AIS . . .

I think the UK Coast Guard make DSC the default calling protocol. I always call them on DSC and they seem to always call me that way.


I have received DSC calls from other coast guards. Years ago in Estonian waters, I got a DSC call from the Estonian Coast Guard asking me, of all things, if I was aware of shallow water ahead. What service! I guess the guy had extra time on his hands.


Once in Finnish waters, I got a DSC call from the Finnish Coastguard asking me if I were aware that I was about to cross into Russian waters. I laughed and told him I was about to tack.


I guess it's not surprising that Coast Guards will be ahead of most of the rest of us in adopting these new protocols.

[geoffschultz]

I use DSC all of the time to make VHF calls to other boats when I don't want the whole anchorage to follow. Very useful. I've also used it to contact ships when they don't respond to a standard hail.


I've never used DSC on my SSB, nor do I know how to use it, despite having tried to figure it out.


-- Geoff