MMSI Question

Mar 31, 2012
139
Nord Cantieri 38 St Marys
Having been out of the game for a bit, we are replacing old obsolete electronics in our current refit. I have just purchased a new VHF radio and have finally applied for our first MMSI number. (Stop laughing, The last VHF rig lasted 43 years).

We have the ships radio and a handheld that stays with this boat. Do we program the same number into both radios? Or do I request a second number for the handheld?
 

senang

.
Oct 21, 2009
304
hunter 38 Monaco
That doesn’t answer the question of the OP. I faced the same question some years ago and after research and hesitations opted to program the same MMSI on main and HH VHF. Keep it simple. Anyway is I take the HH on a charter boat and I have to send a Mayday the HH will transmit my Lat/Long, the main info CG entities need for rescue.
 
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Mar 31, 2012
139
Nord Cantieri 38 St Marys
Thanks guys,

You both answered my question. My suspicion has been confirmed.

On another note: Senang, I am very jealous. I have flown over Monaco many times on my way to Italy and Spain. But I have only seen that coastline from 35,000 feet. Lucky you to live there :cool:
 
Oct 22, 2014
20,993
CAL 35 Cruiser #21 moored EVERETT WA
Sail Master. Not to rain on the parade, You might explore this a bit further. If you are wearing the HH and you go in the water. You hit the DSC button to call the boat to come pick you up. There is likely no answer. You're in essence trying to call yourself.

I learned this after I had programed the HH and the VHF with the same MMSI. A suggestion is to get 2 MMSI's. The FCC license for the boat and a Free MMSI form BoatUS for the HH. This way both radios can be called using DSC and each can be programed with the current data such as a change of address if you are taking your HH on a charter.

That said, I have not yet sent my HH back to a dealer to get the radio reprogramed for a new MMSI.
 
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Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
We have the ships radio and a handheld that stays with this boat. Do we program the same number into both radios? Or do I request a second number for the handheld?
Same number into both radios since the MMSI number stays with the boat. That is exactly what I did on my new to me sailboat.
 

Ward H

.
Nov 7, 2011
3,645
Catalina 30 Mk II Barnegat, NJ
The MMSI number belongs to the boat not the radio.
Not necessarily.
On my last boat I had two HHs, one without DSC/MMSI. I kept the HH with DSC/MMSI and went into BoatUS/MMSI and edited all my boat info for the new boat.
If I was selling a boat with a radio with MMSI then I would let the MMSI go with the boat so the new owners do not have to worry about going through the hassle of changing the radio MMSI number.
 
Nov 18, 2010
2,441
Catalina 310 Hingham, MA
Sail Master. Not to rain on the parade, You might explore this a bit further. If you are wearing the HH and you go in the water. You hit the DSC button to call the boat to come pick you up. There is likely no answer. You're in essence trying to call yourself.

I learned this after I had programed the HH and the VHF with the same MMSI. A suggestion is to get 2 MMSI's. The FCC license for the boat and a Free MMSI form BoatUS for the HH. This way both radios can be called using DSC and each can be programed with the current data such as a change of address if you are taking your HH on a charter.

That said, I have not yet sent my HH back to a dealer to get the radio reprogramed for a new MMSI.
This is the best advice. This also means you can do MMSI calling between the handheld and the boat VHF. This is good for security so other people don't know someone is alone on the boat.
 
Nov 21, 2019
21
Catalina C30 4200 Muskegon, Michigan
yes! same number for all your vhf radio's used on "that boat"
 
Jun 7, 2007
50
Caliber 33 E Tawas
Another thought. If you ever plan on cruising to ports outside the US (eg Canada or Caribbean), you'll want to acquire your MMSI from the FCC. There's a cost (currently $220 for a 10 year license) but your number will be entered into the international database (ITU?) The free MMSI from BoatUS is only good in US waters. I'm in the Great Lakes but now plan to cruise Canada. Just received the new MMSI and have my fixed and handheld radios boxed up and ready to ship back to remove my BoatUS numbers. Too bad they're not compatible.
I also use the same number on both radios.
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
Sorry to revive an old thread but I just got a new HH VHF with the DSC feature. I went to the USPS website and had a MMSI # in a few minutes. Actually I just wanted to create an application and go back to it later but I pressed a button and it was done. So my intended use for the radio is for RC work here. My boat is actually still up on Long Island bleeding stowage fees from me. So in the RC work we use a variety of boats. I would only use the DSC feature if there were a serious injury, medical emergency, MOB not instantly recovered, or other on the water emergency such as collision or fire on one of our boats or perhaps a nearby vessel not in our fleet. Would this use be in violation of the law? I've read on this forum that there are some hefty fines.
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
DSC could be handy for a race committee as the call goes directly to the registered VHF. That is DSC's intended purpose. The MMSI is sort of like a phone number. It also makes the initial part of the call private. This could be handy if the RC wanted to talk to the Mark Boat without alerting others on the race course. Savvy racers try to follow the RC's communications so they can get a jump on the competition.

Using the Panic Button when there is not an emergency is just as illegal as making a false MayDay call on channel 16 and it is easier to trace. The authorities do not take kindly to false alarms.
 

DArcy

.
Feb 11, 2017
1,690
Islander Freeport 36 Ottawa
In Canada you are supposed to register all radios on the boat to the same MMSI. For a handheld not associated with a boat you can get an MI (Maritime Identity) number. It is the same as an MMSI but has an "8" preceding the 3 country ID digits. This is supposed to be a way of letting rescue authorities know they are communicating with a handheld since it may have a more limited battery and range.
 
Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
This is good for security so other people don't know someone is alone on the boat.
We use the dsc calling between radios all the time, to the point Id forgotten this fact.
Its nice to be able to turn down the chatter and know the call is for you when it rings.
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
Well I put the number I got from USPS into the new radio for better or worse. I certainly wouldn't use the panic button unless the boat I am on has a big problem. In reading the instructions the procedure isn't as simple as just pressing the button. It sounds to me like something that should be practiced. I think there is a procedure for that but I would want confirmation from a knowledgeable person before trying it. The manual is not as clear as I would like and some menus just don't function as described. I have a number of other questions which may come out in this thread or another.
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
The same one I have sitting here on the desk with the manual. The manual is a bit daunting at 112 pages for a handheld VHF! :yikes:

The button needs to be pressed for a few seconds. It then sends out a DSC emergency call and the call keeps repeating until the USCG sends an acknowledgment signal and then the radio changes to Channel 16. The default message is "Undefined Emergency" and the Lat/Long It is all automatic.

There is an option to encode a particular distress message which requires some button pushing, but this is not necessary. This would be handy if the VHF is in a fringe reception area as it would notify others of the nature of the emergency. Digital signals often transmit more clearly than analog because they go out in short bursts and cut through the noise when voice contact may be garbled.

Time and Position can also be entered manually, but who would want to do that and why?
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
Assuming an emergency manually entering lat and long would take valuable time. No one would want to do that and I wondered why even include that capability. Or change GPS time?
I'm trying to understand what the functional difference is between the Dual or Tri monitoring and the channel scan. If I understand the manual, both would play a transmission on the selected channels. The scan seems to include a weather station which is OK but the channels scan so fast it's hard to tell. Also the power is obscured by the flashing in scan but is visible in the dual. Oh, and I set it up for priority scanning. Any enlightenment?
I'll save some of the other features for another post.
 

DArcy

.
Feb 11, 2017
1,690
Islander Freeport 36 Ottawa
I have the HX40 but it sounds like the functions are similar. Channel scanning needs pre-prorammed channels and sets the radio to cycle through all the programmed channels equally. Multi watch looks easier to set up, just select the channel you want to monitor then use the menu key to select DW and enter. Now you are monitoring 16 as well as the channel you selected (or 16, 9 and the channel you selected if you set it to triple watch)