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williamsburg

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I finally got around to entering my MMSI numbers into the VHF (Uniden Solara) and connected the NEMA "IN" wire from the radio to the NEMA "OUT" from my Garmin GPS. The small 'GPS received' icon appeared on the radio display, telling me the position information from the GPS has been received by the radio. For some reason this is very unsatisfying. How do I know when I am in the process of sinking and push the red emergency button the Mayday Call and location information will be transmitted. We can test every system on the boat except for this vital one. Is there any way to test without being jailed by the Coast Guard or running afoul of the FCC. Should I switch to 1 watt, get my neighbor to turn to channel 70, and push the red button, and if caught claim my grandson pushed it by mistake.
 
williamsburg":3dv4ev9z said:
I finally got around to entering my MMSI numbers into the VHF (Uniden Solara) and connected the NEMA "IN" wire from the radio to the NEMA "OUT" from my Garmin GPS. The small 'GPS received' icon appeared on the radio display, telling me the position information from the GPS has been received by the radio. For some reason this is very unsatisfying. How do I know when I am in the process of sinking and push the red emergency button the Mayday Call and location information will be transmitted. We can test every system on the boat except for this vital one. Is there any way to test without being jailed by the Coast Guard or running afoul of the FCC. Should I switch to 1 watt, get my neighbor to turn to channel 70, and push the red button, and if caught claim my grandson pushed it by mistake.
Click to expand...

:lol: :lol: If I remember there are lots of Coasties(USCG) in the bay there? I think they will hate that test :wink: You can put in your neighbors MMSI# and call him(on 16) if it works it will switch to 70 your lat & lon will be displayed on his radio & visa versa. :mrgreen: :beer
 
From US Coast Guard:
"TESTING YOUR VHF DSC RADIO
Exchange routine calls on CH70 with another suitably equipped vessel. It is illegal to send a false distress to test your radio."

Boat US, Chuck Husick's column:
"To perform the test with a DSC radio select a working channel (not channel 16), enter the MMSI of a friend’s radio or that of a marina or yacht club and press the “enter” button to send the DSC hailing message. If the called station receives your call it will usually respond with a digital acknowledgment message that will appear on your radio’s LCD screen and then switch to the working channel you selected for voice communication. Under no circumstance use the distress key to make the radio check call."

If you have the output of the radio hooked up to a chart plotter it will display the location of the sending vessel. I found this to be easiest to install on the Standard Horizon Radio, to the Standard Horizon chart plotter.
 
Thanks! I'll give this a try. I still have fear that if I ever have to push the 'red button' I will see "Error xxx" on my VHF display. Or the Coast Guard will return with "We have received your distress call. The MMSI you have given is, according to our records, attached to a 54' Donzi currently impounded by the DEA in Miami. Please correct your MMSI registration. Coast Guard out."
 
My radio display's my coordinates so although I've never tested the DSC function I'm confident that the radio has my location. If you truely want the coast guard to know your sinking invest in a PLB. They can be had for under 1/2 a boat buck. I'm not even sure that the coast gaurd is fully using DSC yet or not. I seem to remember that they were working on their non-commercial system but have never heard anything more on this subject.
 
Like Flapbreaker--we have two Personal Locator Beacons. I would not put much faith in the DSC system yet. If you are going offshore, you want that 406 MHZ Satellite to pick up the distress signal.
 
My neighbor Greg (the guy who has taken me sailing) recently toured Coast Guard Station Seattle and got the straight scoop direct from the horse's mouth.

Rescue 21 is fully operational in Seattle and a few other places around the country. In Seattle, their direction finding equipment instantly locates you as soon as you key your VHF mike, whether you have DSC or not. DSC is fully operational too, and they are listening. If you have DSC not only do they know where you are but also who you are and what your vessel is. Your BoatUS MMSI registration works for DSC in the U.S. - the Coast Guard in fact is recommending you get your MMSI number from BoatUS or SeaTow.

So your chances of getting help quickly here are immensely better than they used to be.
 
One thing to remember, is that there are two "sources" of the MMSI numbers--one is that which comes from Boat US/Sea Tow/Power squadron--the other is from the FCC--which is issuing those for AIS. AIS "B" is very close to being approved for the United States Waters--and when it is, you will find many boats using it. As I understand it, the Boat US/Sea Tow MMSI numbers can not be used with the AIS units for their registration or in the international database.

In fact this is addressed in the Boat US MMSI registration forum:

"USCG and FCC information
1. If you are required to carry a VHF License assigned through the FCC or plan to obtain one, do not complete this form. An MMSI has already been assigned or will be assigned to you in connection with your VHF License. Please call the FCC at 888-225-5322 (select option 2) to obtain or verify your FCC assigned MMSI number.


2. BoatU.S. assigned MMSI data is stored in the Coast Guard SAR database. It is not included in the International SAR database.


3. If you are voluntarily licensed but will be cruising in U.S. waters only, you may use the BoatU.S. assigned MMSI number, however, keep in mind that should you decide to cruise in international waters in future, the MMSI data would not be included in the International Search & Rescue Database."

Both the MMSI number and the EPRIB number are items which are to be included when you get an AIS registration. AIS information is at:
http://www.yachtingmagazine.com/yachtin ... 12,00.html

This is slightly dated, and it has taken two years to get the Class B approval from the FCC. But there has been a lot of information on AIS on Panbo on Oct 19th. The class B units (which have a transmitter, as well as the recievers on the cheaper units)--are still not expensive in comparison to what safety they may give in crowded harbors.

To complicate the issue slightly more--the US coast Guard radio site says the following to the question if a US vessel needs a FCC license for its VHF radio when voyaging to Canada:
"Technically, yes. Although the FCC no longer requires boaters having a VHF radio for domestic use to carry a ship station license, ship station radio license for my boat since the FCC eliminated its licensing requirements. U.S. boaters are supposed to obtain a license from the FCC before coming to Canada. We understand Canada, like the US, do not require boaters with VHF radios carry ship station licenses.

But FCC says: "If you travel to a foreign port (e.g., Canada, Mexico, Bahamas, British Virgin Islands), a license is required. Additionally, if you travel to a foreign port, you are required to have an operator permit. "
"MMSI numbers issued by other authorized entities are valid only for ship stations that do not have FCC-issued licenses. "


Many of the small boats are not getting an FCC license for Canada--and just the "operators" permit seems to be accepted. But it might be prudent if at some time, you were to plan any international voyage, to get the MMSI number from the FCC (also means a few $$$).

There is a Coast Guard GMDSS task force, which recommended that the MMIS Databases be combined.
 
williamsburg":39z42za6 said:
Thanks! I'll give this a try. I still have fear that if I ever have to push the 'red button' I will see "Error xxx" on my VHF display. Or the Coast Guard will return with "We have received your distress call. The MMSI you have given is, according to our records, attached to a 54' Donzi currently impounded by the DEA in Miami. Please correct your MMSI registration. Coast Guard out."
Click to expand...

Is your cruising ground normally served by Coast Guard Group Eastern Shore? I can't tell, but looking at the map suggests that it would be. If so, you're in luck, because this is one of only six stations that have implemented Rescue 21, the package of technology that allows triangulation of transmission locations and full-featured DSC handling.

See http://uscg.mil/rescue21/about/impsched.htm
for current status and roll-out schedule.

I toured the Joint Harbor Operations Command facility in Seattle, and golly, was I impressed. You can read my summary here:
http://www.navagear.com/2007/06/joint-h ... ns-part-1/
http://www.navagear.com/2007/06/joint-h ... ns-part-2/
 
Although theCoast Guard is in the process of implementing it's Rescue 21 program, there's no reason to wait for that to come on-line to have your DSC up and running. We were mid-way between Key West and the Dry Tortugas, without another vessel in sight, when a DSC distress signal came in. At least three other vessels responded on Channel 16, one of which then relayed the information to the Coast Guard. Bottom line: if you're most anywhere in or around the U.S., and send a DSC distress signal, there's at least a chance (probably a good one) that the Coast Guard will get the information, and also a chance other vessels will be able to respond with assistance.

So, if you have a DSC equiped radio (all new ones are), and a chartplotter, there's no reason not to go to the Boat U.S. web site, get an MMSI number, program it into the radio, and connect the plotter's NMEA Out + to the radio's NMEA In +, make sure they're both grounded (that's the NMEA Out - and NMEA In -), and make sure your position displays on you radio. Test the setup as discussed on previous posts if you're uncertain, and you're set to go. If you have a radio with NMEA Out, then go ahead and connect that too (radio NMEA Out + to plotter NMEA In +), and your plotter will be equiped to display DSC position information for distress and other DSC calls you receive).

If you have the equipment, but are undertain about getting an MMSI, or the electrical connections, just ask for help. This one is not rocket science, and there is no shortage of people who are willing to help.
 
Almas Only":m3p4sgmg said:
Although theCoast Guard is in the process of implementing it's Rescue 21 program, there's no reason to wait for that to come on-line to have your DSC up and running. [...] Bottom line: if you're most anywhere in or around the U.S., and send a DSC distress signal, there's at least a chance (probably a good one) that the Coast Guard will get the information, and also a chance other vessels will be able to respond with assistance.
Click to expand...

Oh, absolutely. I hope I didn't give the impression that DSC is useless in those vast areas where the Coast Guard isn't yet equipped to utilize it fully. I guess it could have come across that way.

Yes, somebody will probably receive your transmission...probably other DSC-equipped vessels, including DSC-equipped Coast Guard vessels. So it's very much worthwhile to get it all set up properly. But Coast Guard shore stations may not be able to get all your vessel data at the push-of-a-button, for instance. A rescue operation will get underway about as quickly, but there will be less certainty about what sort of vessel is in trouble, how many persons are likely to be aboard, etc. That's all I'm saying.
 
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