Emergency Radio Procedures / How to read and say GPS coordinates

@gmacd81 - Is Rescue 21 able to detect your position if just hailing over Ch16 on a DSC radio, or do you need to push the DSC distress button for Rescue 21 to see your position?
There is a bit more to it.
  • The boat must have a DSC enabled radio; you will know this simply by it having the red distress button. Most all modern hard installed VHF radios have DSC.
  • You must register and obtain a Maritime Mobile Service Identity (MMSI) which is a nine digit number that is then entered into the VHF. Once the number is entered it is permanent and cannot be changed unless the VHF is returned to the manufacture. If someone (previous owner) has already obtained and loaded the MMSI into the radio it needs to be transferred to you the owner of the vessel. There is a process for that.
  • The VHF must be integrated with the GPS so the DSC has GPS location data. Some VHF radios come with internal GPS but most are externally integrated via NEMA 0183 or NEMA 2000.
When the red distress button is depressed and held until the VHF indicates Channel 70 and the GPS coordinates you can release the button.
The VHF will then continuously transmit the distress signal with MMSI data and coordinates until someone acknowledges, then the VHF will automatically switch to Channel 16 at which time the nature of the distress can be discussed. If no one on the distressed boat responds on CH 16 (Captain is down for example) the Rescue 21 system still responds to the emergency.
The Rescue 21 system is integrated with the radio's MMSI registration and when a distress is transmitted the GPS coordinates, the registration data for the boat, and registrant's name are received by Rescue 21. Note also that the VHF transmits at maximum power on DSC and due to the digital nature of the signal the transmit distance is greater than the other simplex voice channels.

There are other desirable features for DSC like ship to ship private calling. Consider your MMSI your cell phone number. So, if you have a friends MMSI and you want a private two way call then you can select DSC Call from the VHF menu then enter their MMSI then select the channel you desire to have the conversation on and then transmit. Your friend's VHF will "ring" much like a telephone and when they pickup and acknowledge both VHF radios automatically switch to your selected channel then you can have a private conversation. Due to the digital nature of the DSC even if someone else is monitoring the channel you are on, they will not hear the conversation.

Regardless, hynespa, I like your reference card and if you don't mind will plagiarize but probably break it up into a couple of cards. I'll probably have a stand-alone emergency equipment card which will be placed in several locations on the boat. If you have your MMSI registered the emergent condition process on your card can be simplified. But, knowledge on using CH 16 for Pan Pan or May Day by passengers is also important.
Tom
 
I appreciate the feedback from everybody. Incorporating feedback received by @Stee6043 , @Fat Tony , @iBoat Skipper Doug , @RollerCoastr , @gmacd81 and @ttmott I updated the instructions to take into account the DSC distress button feature of my iCom radio. As mentioned previously the MMSI has been re-registered through Boat US with my contact information after the eventual cooperation of the previous owner. Here are the revised instructions:

Screen Shot 2018-09-22 at 10.19.16 AM.png
 
Side point... On many GPS machines, you can select how you want to display the coordinates. If your machines allow that, you may be able to "sync" them. Would certainly make things a little easier.

Good thread, though. Thanks for starting it. Got me thinking about making up a cheat sheet, as well.
 
I installed an Icom M400BB just for this reason, including getting the GPS and MMSI#. I wanted 1 button simplicity for the wife.

However, this thread has been very educational in regards to what happens behind the scenes with this radio. Additionally, I hope you don't mind if i lift some of your cheat sheets for my Ops manual!
 
On a side note, but important to us inland boaters. Does this work on inland lakes? I've been told that the local DNR and water patrols here in GA prefer cell calls. I find that a little suspect, as the cellular 911 has known issues with location that cant be better on the water than on land.

I have been a proponent to dock mates that a VHF is a better way to get immediate help. At least on Lake Lanier I think there is limited use of VHF in general, either due to old equipment, failure to turn it on and monitor, or they are not even installed.

I think I need to investigate this a little more.
 
On a side note, but important to us inland boaters. Does this work on inland lakes? I've been told that the local DNR and water patrols here in GA prefer cell calls. I find that a little suspect, as the cellular 911 has known issues with location that cant be better on the water than on land.

I have been a proponent to dock mates that a VHF is a better way to get immediate help. At least on Lake Lanier I think there is limited use of VHF in general, either due to old equipment, failure to turn it on and monitor, or they are not even installed.

I think I need to investigate this a little more.
Here you go Dave
https://www.navcen.uscg.gov/?pageName=mtNds
 

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