Distress Button/MMSI Question

[jason78]

In preparation for my trip to the coast next week, I have managed to get GPS Coordinates flowing from my GPS to my Standard Horizon Quest VHF Radio.

Will the VHF now transmit the coordinates if the Distress button is pressed or do I still need to assign an MMSI number for this Distress feature to work? If I enter an MMSI does it transmit MMSI info or coordinates with every transmission or just when "Distress" is pushed?

Thanks!

 

[Tomco]

If I remember correctly it does transmit the MMSI and the coordinates - the MMSI will give the Coast Guard the specifics of your boat (color, size, style ... don't remember what other questions were on the form). Not sure about needing it for the distress button to work ... I set mine up with the MMSI from the beginning.

 

[magstang1]

Your VHF will function as a normal radio when making routine calls. No personal or positional data transferred.

If you make a DSC call by typing in someone else's MMSI your position will be sent. More than likely if you're calling someone like this you already know them and sharing your position won't be an issue. It could be a resource if trying to meet up. Your GPS position will be sent rather than explaining your position behind the white boat with the tan tops.

Wether or not you need an MMSI for the distress function to work, I'm not sure. Why not get one? It's free and it might save your life. If I were in a situation where I felt I needed that level of help I would want everything known to the first responders possible.

You can make test DSC calls. You can not test the distress button. You can, but you're not supposed to. I did have the opportunity to see the distress function in action. A boat around me was "testing" his. My VHF and GPS lit up with a warning banner. The signaling boat popped up on my GPS screen and his MMSI was already keyed up on my radio. I knew his location and had a direct line of communication with his boat. So did everyone that had DSC tied to their plotter in his broadcast range. He was quickly addressed and reprimanded on 16.

In my opinion it's a fantastic option to have. If things get desperate I push one button and jump off.

I have a Garmin 740s networked with a Garmin VHF 100.

 

[jason78]

Thanks for the information so far. I was going to get an MMSI number from BoatUS but it says if you ever plan to visit an international port (including Bahamas) you have to go through the FCC to get some kind of other government radio license and they will also issue an MMSI in conjunction with that license. Given the fact that one day I would love to go with a group to Bimini, maybe I better go the FCC paper trail route? Went to FCC website and looks like it will be the typical 3 month process to figure out their website and get through the paperwork with them. So I will probably have to go without an MMSI this time.

The Boston Whaler owners club just did a group trip to Bimini last week. They had some pretty cool pics on facebook. Wish I could take the Sea Ray but that is not in the cards right now due to lack of sufficient tow vehicle.

 

[magstang1]

I know it's hearsay but I remember another member being concerned about the license you mention. Other members chimed in and said don't bother in the Bimini trip thread.

You can always change or delete your MMSI through Boat US. Personally I would hate to be in a situation where it could be beneficial because I may or may not do something in the future. That's a personal decision though. Seeing how seamless the distress feature was, I'll never be without it again.

 

[jason78]

I know it's hearsay but I remember another member being concerned about the license you mention. Other members chimed in and said don't bother in the Bimini trip thread.

You can always change or delete your MMSI through Boat US. Personally I would hate to be in a situation where it could be beneficial because I may or may not do something in the future. That's a personal decision though. Seeing how seamless the distress feature was, I'll never be without it again.

You make a good point. I could just cancel the free one with Boat US down the road if I needed to. I think I'll go ahead and sign up. Seems like a great piece of technology. Thanks Again!

 

[Fred]

Until your mmsi number is programmed into a new radio you cannot use any of its DSC functions.
In other words you cannot call anyone or use the may day button.

 

[trit21]

As far as going thru the FCC for the MMSI number it is not needed. Basically what happens when you get your MMSI from FCC (which by the way cost like $120 from them) it goes into an international pool. If you ever need to press the distress button, supposedly the Bahamian authorities will be able to pull up your information. If you only register from BOATUS, then the information is not in the international pool and is only available in the US. Now, I go to the Abacos every year as well as other that have been doing it for 20+ years, and not one of them has the FCC MMSI number. If you are going across, you should have an EPIRB anyway since VHF will not reach the authorities out in the deep blue. It may reach boats around you but once it sinks or the power is cut off, your VHF also dies. EPIRB is the way to go for a crossing.

 

[Molson]

What a sec....some radios don't allow you to change the MMSI once you input it, so make sure your radio will let you do so. With my Northstar, I think the only way to change it is to send it back to the manufacturer, which of course no longer exists. Definitely check before you make a costly mistake.

Standard Horizon is the same. I just installed a GX1700 (Build in GPS) and no DSC functions would work until I inputted my MMSI. Its a great feature. Polling, position reports, etc. I used the DSC TEST feature over the weekend, it was ACK in seconds, and the CCG even called me on 16 to advise that it worked great. Not enough people use the DSC functions around here. Most I've talked to said "Whats an MMSI??" :smt021

 

[magstang1]

From the BoatUS website:

DSC VHF radios WILL:

• Have a One-Button Emergency Transmit capability that sends out the vessel's unique MMSI number and, if properly connected to a GPS or Loran, the vessel's latitude/longitude position.
• Continue sending the distress signal even if the captain is incapacitated.
• Allow for a non-experienced VHF user to send, with the pressing of one button, a goof-proof continuous distress message.
• Privately hail another DSC equipped vessel, or shore station, with a known MMSI number. Like having a "VHF phone number" this avoids having to monitor high traffic channels just for a hail from your boating buddy. It even "rings" your radio, similar to a telephone, notifying you that you have a call and then switches you automatically to the channel your caller is waiting on.
• If properly connected to a Loran or GPS, a "Polling" feature transmits your vessel's position, in digital display, that can be monitored by DSC equipped home station/fleet station or boat.
• Fully function as all other regular VHF radios.
• DSC VHF radios WILL NOT:
• Be monitored by the U.S. Coast Guard in all areas until that area's Rescue 21 system is operational (see map). However, DSC equipped vessels in the area may receive your distress call.
• Provide private radio to radio voice communication. After the "private" digital hail, DSC radios automatically switch to an open VHF channel for voice communications. Voice communication is carried on an active working channel chosen by the caller making the initial hail.
• Take advantage of all these functions without first registering for a unique MMSI number that is free for the boaters who register on this site.

DSC (Digital Selective Calling): Marine radios equipped with DSC serve as one facet of the GMDSS. A DSC equipped radio has all the features of your current VHF radio, and more. DSC technology built into your modern marine radio allows the radio to perform a number of enhanced functions. It permits direct contact with another specific DSC capable unit, polling other DSC units for their locations, and various other special features. The most significant function is its ability to transmit an automated distress call.

In an emergency, one push of the distress button transmits the distress signal conatining your MMSI # and, assuming a built-in or external GPS link, your Lat/Lon information to USCG and all other DSC capable receivers within your broadcast range. It continues to transmit until acknowledged, even if you can't be attending it.

Channel 70 has been designated as the VHF/DSC digital call channel, but you do not have to select Ch 70. That happens automatically whenever a DSC function is activated. Once the DSC call has been confirmed by the receiving unit, both parties are automatically switched to the pre-selected working channel for voice transmission. . Once the DSC call has been confirmed, both parties are automatically switched to a working voice channel.

MMSI (Maritime Mobile Service Identity): You must obtain (do not create your own) an MMSI and enter it into your DSC capable marine radio in order to enable the unit's DSC functions. The MMSI number serves as both a nine digit “telephone number” and as a unique identification number that the U.S. Coast Guard will use to identify you in an emergency. This is especially important if communications were to break down.

During normal communications, vessels with DSC capable radios may call each other digitally by using the MMSI as a "telephone number". The signal will only be received by those vessels with the MMSI numbers that were called, after which everyone on the call is switched automatically to a pre-selected working channel for normal voice transmission.

During an emergency, the boater may push a button to automatically transmit a distress call which would include their MMSI number (and location if the radio is linked to a GPS receiver) to every DSC radio within range. When the U.S. Coast Guard receives the alert, the unique MMSI number will be used to access the related information on file (emergency contact number, type of vessel, etc.) to help them mount a more efficient rescue effort.