I just got a Standard Horizon Handheld VHF HX850S with GPS and DSC (Digital Selective Calling) For the boating I will mostly do this should be sufficient. I went to the BoatUs site to register my MMSI# and I read something that says DSC is really only effective in areas that Rescue 21 is active. For me that means Great Lakes in 2011 or the Ohio River in 2012.

So If I need a Mayday will I have to use it the old fashioned way by hailing on 16? Or will the Coast Guard still be able to respond to my coordinates if I use the DSC distress call, assuming they are in radio range?

Has any body here picked up a distress call on their DSC capable radio.

Al?

I have had a DSC radio since 2002. The original USCG estimate for Rescue 21 for the Great Lakes was to be in 2006, but they keep sliding the dates back.

Even through the USCG will not necessarily be able to respond, its my understanding that any boat within range will receive a distress call.

And there is one other aspect of DSC; buddy lists. If you have a boating friend, you can put their MMSC number in your contact list on your radio, and if you want to connect to them, DSC will establish a clear channel and put both radios on that channel.

Of course, you and yourr buddy's DSC must have the buddy capability (not all radios do). And some radios - for instance, my Icom radio does this - once your buddy calls (or even a ship in distress), the radio can plot the location on your chartplotter, and even plot a course.

Some of the earlier DSC radios did not quite do this; my old 2002 era Standard Horizon Intrepid would not plot to the chartplotter; so there is a lot of different capabilities depending on the radio. I believe the only thing the radio must support is emergency calling, not necessarily plotting a chart or buddy calling. But the older radios were more limited in this regard than the newer designs.

At this point, its all theory as I have yet to find anyone local having a DSC radio so that I can play with the radio. My sailboat buddy has one but he doesn't have his chartplotter hooked up to it. I'll probably convince him to connect it up so that we can play with the DSC functions.

Thanks Al,

The radio I have is portable no built in on my bowrider. It has an internal GPS. I do have buddy lists, at least I think I do I can put other MMSI numbers into memory any way. Obviously I can't plot a course but it does have a NMEA hook up.

I can also poll my buddy's position. The manual states that If I receive a distress call it will give the position. and switch me to 16 to listen.

I would have to think that the USCG would have a similar set up. So that my distress signal would at least give the position. And that would at least allow the CG a quicker response. I can actually also choose the nature of my emergency fire, explosion, grounding etc. although I don't know what the CG would receive.

I don't know anyone near me with DSC either so I can't play. After I get my MMSI number I may go to the local CG station and ask what info they receive and if it is actually better than the old way and call them with my DSC boater to boater option.

Still curious to know if anybody has received a DSC distress call?

Check out this radio tutorial.

USCG interactive tutorial

No, I have never received a distress call via DSC.

I would think that the DSC would be a good idea in an emergency but if you have the time I would still put out the mayday the old school way.

If you didn't have the time at least there would be a further chance that someone would pick it up. There are many DSC radios out there and even if the CG doesn't technically have their system up and running I would be surprised if they did not have a "civilian" DSC radio on thier boats. Commercial traffic also have them on board so your chances are definately better.

Tglee,

I went through that tutorial. That's actually where I got my question.


Prober,

Based on my radio operation and the tutorial I think that is how it works any way. After you send the distress your radio switches automatically to 16. If you receive a Distress over the DSC your radio will switch to 16 for you to listen to see if you can be of assistance. At least mine works that way. So you still have to speak the nature of your distress.

I suspect the CG will receive the Distress and either wait for the nature of the call over the analog system or ask how they can be of assistance.

Either way I am sure it could save precious time as at least a location will be transmitted.

Its my understanding that only the MMSI number and GPS lat/lon is transmitted by your radio, as well as the nature of the emergency. I may be wrong, but I do not believe that your boat name is included in the transmission as stated in the tutorial.

Rather, its my understanding that the MMSI number is used to look up the database entry that you created when you got your MMSI number.

The database has fields for your boat name, boat description, owner, next-of-kin, and similar information, and I think this is the source of that information. However, it is still of trememdous help as they can stil find the boat description and name, which is a huge help during a rescue.

While we have not received any DSC distress calls, my understanding is that other DSC equiped vessels that receive your call will have your location appear on their chart plotter if it is able to do so.

That is my understanding as well, provided, as you say, with a properly equipped chartplotter AND VHF radio. Not all VHF radios can send plot instructions to a chartplotter, and this is where the different brands vary quite a bit.

The Standard Horizon radio on my last boat would receive lat-lon data from the chartplotter for sending the position when I sent a DSC signal, but it had no provisions to send a message to the chartplotter to plot a location from a DSC reception; either emergency or not.

I know this because there was no NMEA0183 output connection on the Standard Horizon - only NMEA0183 input.

In contrast, my current Icom specifically states that it does the chartplotting function, and, well, it has a NMEA0183 output connection as well.

There are so many different configurfations of VHF radios in this regard that you should check the specs before purchase if this is an important feature.

Al, we have a SH CP155C charplotter and SH PS-1000 VHF radio. This combination does show the position of a DSC distress call or the location of a polled vessel. This in one of the main reasons I selected this pair.

Unfortunately, I don't seem to have any local friends that have the same capability, so I have never tested it. And happily, we have never received a local distress call.

Courtesy of the VHF, we did get to watch a sherrif aprehend a drunk on a jet ski that had earlier run into his friends boat.

I am sure that feature varies with the model of radio.

I didn't mean to imply that all SH radios do not have that capability, but some don't (as the one I had didn't).

I am sure other brands of radios have certain models that do not support the chartplotter feature either.

So if it is a feature you want, make sure the model radio you are considering supports it.

I do wish there was a way to test the distress signal broadcast without sending a real one.

A friend also has DSC and has also secured an MMSI but we were not able to call each other. He has since sold his old boat so I'm not sure what he has dome about an MMSI on the new boat.

On my Uniden 525 it does seem like an overly complex process to send out a digital distress call. I do hope I remember the steps if I need it.

I think at this point, your chances are better if your chartplotter and radio are from the same manufacturer.

This is a great concept, but it does not seem that many are embracing it...