DSC distress signal monitored by USCG?

[mpel]

My VHF radio has a distress button for using Digital Selective Calling (DSC) protocols to automatically transmit an emergency condition, and it is interfaced with my GPS to relay coordinates in this manner. I know I still need to register my MMSI number. My question is whether the Coast Guard is officially and actively monitoring this form of distress call? The USCG web site indicates that "DSC distress alerts will be received by the Coast Guard when Rescue 21 is fully operational in your area." What is unclear to me is whether this is currently operational in my area (Rhode Island) or any other. I've encountered mixed opinions on this matter from fellow boaters, but so far have not located an authoritative source.

Thanks for any info.

Mike P.

[DougSea]

My VHF radio has a distress button for using Digital Selective Calling (DSC) protocols to automatically transmit an emergency condition, and it is interfaced with my GPS to relay coordinates in this manner. I know I still need to register my MMSI number. My question is whether the Coast Guard is officially and actively monitoring this form of distress call? The USCG web site indicates that "DSC distress alerts will be received by the Coast Guard when Rescue 21 is fully operational in your area." What is unclear to me is whether this is currently operational in my area (Rhode Island) or any other. I've encountered mixed opinions on this matter from fellow boaters, but so far have not located an authoritative source.

Thanks for any info.

Mike P.

Hey Mike,

Rescue 21 is now operational on nearly all of the non Great Lakes shores of the continental US. See this link for a coverage map and some great information:

http://www.gdc4s.com/content/detail.cfm ... 0e9f7972fa

[mhanna]

DSC sends out an alert not only to the Coast Guard when you hit that button but any DSC VHF radio in range should go into alarm. Now how many people know what that means is another thing.
I found this on "thehulltruth.com"

No matter where you boat, in an emergency your DSC mayday signal will be received by every DSC-capable radio in range and will sound a distinctive audio alarm, regardless of the radio’s volume control. Connecting the radio to a GPS or Loran can be critically important as everyone receiving your call for assistance will know your precise location and may be able to assist long before the Coast Guard.

Trying to read the information on the screen and then type this into your GPS could be challenging especially if time is critical. If you have a DSC radio that talks back to your GPS and its configured properly the position of the alert should pop up on it making it much easier to identify where the alert came from. There is another thread here in the electronics forum that talks about AIS viewtopic.php?f=27&t=4196 and in there is a radio I have bought where it should do the above as well as AIS.

I have connected it up and as of right now I get all the Lat, Long data on the VHF, once the boat is unwrapped and the antenna goes up I will report back on how it works.

More info on how to test the DSC feature is here http://www.boatus.com/gov/rescue21_update0906.asp

Matt

[Ron222]

Glad to learn the DSC will alarm if any other boat presses the DSC button within range. For Paumanok that is probably around 20 nm. For those who have connected their VHF to the GPS I am wondering how you connected the wires. I have a new Std Horizon VHF that I need to connect to the Garmin 182C. Of course, the colors are not standard and the 182C instructions are sufficiently ambiguous to wonder which NMEA (+), NMEA (-) and NMEA (com) to pick. I will call Garmin to get this clarified. But, the wires are soooo fine (thinner than 22 gauge) that I thought there must be a special butt connector for such fine wires or, maybe they need to be soldered? The alternative is just twisting them together and use electrical tape but that just doesn't seem the best option. West Marine's smallest butt connectors are 22 - 18 AWG. To use these connectors will require folding the wires several times to get the right thickness. If you connected these wires....how did you do it?
Ron
Paumanok, A34

[jcollins]

This is an interesting post. My DSC alarm goes off about once a month. It is loud! Once I was at least 100 feet away on another pier at my marina and I could hear it. Another time I was cruising with friends. They thought it was some type of engine alarm. Scared the ...well you know, out of them.
But, I have never heard the CG respond after hearing the alarm. I'm assuming it's guys "testing" the alarm button. Believe me, it works.

[joe.baar]

Ron,
Re: connecting those really fine wires, I'm going to try using a voice/data RJ45 or RJ11 plug and jack. The wires don't need to be stripped when crimped into a plug or when punched down on the back of a jack. You would need to keep track of which wire went where but the pin diagram should give a good start in that direction. I also use "electrical grease" (sometimes called "dielectric grease", although it's really just the opposite) on every connection I make.

I haven't actually done this yet so I can't report how well it works.

The Coast Guard apparently estimates that 90% of DSC-capable VHFs are NOT hooked up to a GPS and so are unable to do this reporting. I'm told one of the big issues is a complete lack of industry standards about which wire goes where; and therefore standardized plugs and jacks are not available for this particular connection.

[Ron222]

Joe,
This question has turned out to be more complicated that I thought. I called Garmin and they gave me the wiring colors to connect the 182C to the radio. But, their technical expert couldn't remember how the wires should be connected. After waiting for the Garmin expert to try to remember what was the name of the connector he consult higher management (and probably called their electrical consultants) he got back to me and said "we don't recommend any one method for connecting the wires". However, he did tell me that Garmin is aware of installers using heat shrink butt connectors and soldering with heat shrink wrap. By the way, Garmin never heard of anyone using voice/data jacks. I told him one of my buddies said I should just twist them together and use tape. He told me they do that too. Yikes. I am going back to soldering.
Ron
A 34, Paumanok

[mhanna]

I had to do the same thing when connecting the VHF to the GPS, I used this small gauge terminal strip from Radio Shack.
http://www.radioshack.com/product/index ... Id=2103231

I think it had 8 positions, I cut it for 4, screwed it to the back of the dash and then using a fine screwdriver put the fine wires in it (It clamps down on the wires).
It is working great and if changes are needed later just unscrew..

Matt

[DougSea]

I like Matt's method. It allows flexibility if you need to hook up additional devices, makes it easier to troubleshoot and provides a level of strain relief.

Although the RJ45 sounds interesting...

[dkircher]

Hi all,

I recently wired my Standard Horizon GX 2150 to my Garmin GPS. When I had a problem, the tech at Standard Horizon guided me to a solution in just a few minutes. So if Garmin can't help be sure to call the Standard Horizon number. DSC is a great safety measure. Now if I can only figure out how to deal with the US versus International MMSI issue...

Oh and I simply used 22 gauge Radio Shack wire for the connections. I documented the wire colors, soldered the connections and used shrink tubing to seal them.

[joe.baar]

This has been very interesting. I'm still going to try the voice/data plug and jack because my VHF is not a permanent installation. I put the bracket up on the mate's side dash and stow the radio below - out of the sun and away from prying eyes - when I'm not on the water. The power plug that comes with the Standard Horizon GX2000 is suitable for this use, and the antenna coax connector is also no problem.

[Ron222]

I really appreciate all the ideas and suggestions ! Lots to think about for such a relatively minor issue. Because of the location of the radios vs. GPS on the flybridge and wheelhouse I am going to solder the connections. In the wheelhouse the radio and GPS are too far apart for the wires that are provided with the units (radio attached to roof; GPS on dash). For this installation I have to buy addition wire but am reluctant to use Radio Shack wire. I have seen the difference between marine grade and standard wire. The standard (non-marine grade) wire has a tendency to oxidize over time even if it isn't exposed to the weather. If there isn't marine grade fine wire then I won't have a choice but am now afraid to call Garmin. I may have to wait again for them to contact their consultants for the answer. I will try Standard Horizon this time. Will let you know how this turns out if/when it gets completed. Let us know what happens with your installs.
Ron

[jleonard]

I am one of those 90% that has never hooked it up. I have a secret code number and all that, but never wired it. If I ever do I'll probably twist the wires together and try it until I am assured it works properly then do a permanent solution, method TBD.

[Ron222]

Happy to report to all that I was able to connect Paumanok's GPS units to their respective radios (with plenty of frustration, I might add). Here are some thoughts: 1. The wires are so fine that you need someone to hold the wires if you plan to solder, don't try it by yourself especially after a cup of coffee 2. use shrink wrap tubing larger than the wires because the tubing doesn't slide over the connection if you put tape around the soldered wires as extra protection. 3. remember that the GPS has to be setup to transmit the NMEA information to the radio. The radio isn't setup from the box. and 4. call Standard Horizon whenever possible. They are really great and helpful. Both radios now have the lat/long/time displayed and it was very satisfying after about 6 hrs to run to WestMarine and RadioShack, reroute wires, solder and tape connections, read the manual, call Std Horizon (2x) and drink a beer.
Ron
Paumanok, A34
Westbrook, CT

[DougSea]

There's nothing like that first beer after winning a fight with your electronics! I upgraded the stereo and Sonny IV and ran a wired remote up to the master. I was thinking..."How hard could this be?" Answer; VERY!

The beer was great!

Glad to hear you won this battle Ron! I'm toasting you as I write!