Epirb mmsi

R

ronhugh

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I need to change MMSI number on epirb that came with boat I bought in Netherlands. Have changed on VHF which had to be sent to factory. Just had new battery fitted in epirb, (forgot about MMSI when this was done). Anyone had this done, how? cost?

Thanks

Ron
 
What MMSI on an EPIRB? They are simple devices which emit only their code, which is a long sequence of digits, recorded for convenience in hexadecimal notation.

What you have to change is the association between this hexadecimal number and the details of boat and owner and sundry other data such as telephone number of next-of-kin. For those EPIRBs associated with UK registered boats this association is managed by Falmouth Coastguard- it's not recorded within the EPIRB itself. I suggest you contact them, writing to "UK EPIRB Registry", Falmouth Coastguard, Castle Drive, Falmouth, Cornwall TR11 4WZ. Changing this data is free.

30 seconds Google-ing would have already revealed this, as would passing the VHF radio exam - without which it's illegal to operate the VHF which you've 'already changed'. You should also make sure that the VHF is registered with Ofcom (which I guess you must have done or wouldn't have an MMSI number) - again it's free.
 
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Many thanks jdc, points noted and most useful. I did try Internet search, that along with the response from epirb registry sent me into a beaurocratic maze which even having passed my VHF course proved difficult to escape from.
Ron
 
To avoid confusion it might be necessary to remove the same link between epird ID and MMSI in the dutch registry. Otherwise using the epirb could cause difficulties.
 
jdc said:
What MMSI on an EPIRB? They are simple devices which emit only their code, which is a long sequence of digits, recorded for convenience in hexadecimal notation.

What you have to change is the association between this hexadecimal number and the details of boat and owner and sundry other data such as telephone number of next-of-kin. For those EPIRBs associated with UK registered boats this association is managed by Falmouth Coastguard- it's not recorded within the EPIRB itself. I suggest you contact them, writing to "UK EPIRB Registry", Falmouth Coastguard, Castle Drive, Falmouth, Cornwall TR11 4WZ. Changing this data is free.

30 seconds Google-ing would have already revealed this, as would passing the VHF radio exam - without which it's illegal to operate the VHF which you've 'already changed'. You should also make sure that the VHF is registered with Ofcom (which I guess you must have done or wouldn't have an MMSI number) - again it's free.
Click to expand...

Bit grumpy today?
 
jdc said:
What MMSI on an EPIRB? They are simple devices which emit only their code, which is a long sequence of digits, recorded for convenience in hexadecimal notation.

What you have to change is the association between this hexadecimal number and the details of boat and owner and sundry other data such as telephone number of next-of-kin. For those EPIRBs associated with UK registered boats this association is managed by Falmouth Coastguard- it's not recorded within the EPIRB itself. I suggest you contact them, writing to "UK EPIRB Registry", Falmouth Coastguard, Castle Drive, Falmouth, Cornwall TR11 4WZ. Changing this data is free.

30 seconds Google-ing would have already revealed this,
Click to expand...

Except that this is not true. Not sure what they teach on "the VHF course", but the MMSI *is* coded inside the 15hex number which is programmed into the beacon.

I suggest you google "Cospas Sarsat Technical beacon specifications", which indicates, first the country code part of the 15hex:

A1.2.3 Country Code
Bits 27-36 designate a three-digit decimal country code number expressed in binary notation. Country codes are based on the International Telecommunication Union (ITU) Maritime Identification Digit (MID) country code available on the ITU website (www.itu.int/cgi-bin/htsh/glad/cga_mids.sh). National administrations allocated more than one MID code may opt to use only one of these codes. However, when the 6 trailing digits of a MMSI are used to form the unique beacon identification, the country code shall always correspond to the first 3 digits of the MMSI code.

then specifies the Maritime user protocol, the 6 remaining MMSI digits (after the Country code 3 digits) are programmed into bits 40-75 of the 15hex (callsign if no MMSI available)

A2.2 Maritime User Protocol
The maritime user protocol has the following structure:
Bits Usage
25 format flag (=0)
26 protocol flag (=1)
27-36 country code
37-39 user protocol code (=010)
40-75 radio call sign or trailing 6 digits of MMSI
76-81 specific beacon number
82-83 spare (=00)
84-85 auxiliary radio-locating device type(s)
Bits 40-75 designate the radio call sign or the last 6 digits of the 9 digit maritime mobile service identity (MMSI) using the modified-Baudot code shown in Table A3.


Also, the "Cospas Sarsat Beacon Handbook", page 201 is related to the UK, "EPIRB coding methods" specifies the MMSI to be coded into the beacon 15hex.
The pdf layout is lost but you may find the whole paper on the Cospas sarsat web site.


UKM.2 EPIRB CODING METHODS
Country Code
EPIRB Coding Methods
232, 233, 234, 235
Serial Number
MMSI
Radio
Call Sign
User Protocols (non-GPS)
Non-CSTA, bit 43 = 0
Nationally assigned serial no
Y
Y
N
N
CSTA, bit 43 = 1
Manufacturer assigns serial no
Y
Y
N
N
Location Protocols (GPS)
Standard Location
CSTA,
Protocol code bits 37-47 = 6
Manufacturer assigns serial no
Y
Y
N
N


So yes, changing flag (hence MMSI number) requires the Epirb to be re-programmed with a new 15hex code.
 
Hmm, I was grumpy I admit, but nonetheless I'm unconvinced that our normal 406MHz EPIRBs do contain the MMSI of the yacht. My reasons are that when I bought mine (McMurdo Smartfind) I just bought it. It came with a sheet of paper telling me the Hex code, and I duly filled out the EPIRB's form (now online, see https://forms.dft.gov.uk/mca-sar-epirb/#gf_240) which asked me for the Hex code. This Hex code was never changed or amended, and my identity, let alone my MMSI number, was unknown to the seller. I have just looked at the RNLI website for their explanation of an EPIRB which seems to bear this out

However on reading Roberto's helpful attachments, the country code is included in the bit-field, so that a UK message comes to the UK CG, and a Dutch message to the Dutch without having to go via an international database I surmise. And so I guess it's this bit the OP is keen to have amended - which may or may not be possible of course. So if the country code alone, rather than the full service identity can be termed the MMSI (which I wouldn't have thought it was), then I was wrong: but can MMSI really mean different things in different contexts?
 
jdc said:
Hmm, I was grumpy I admit, but nonetheless I'm unconvinced that our normal 406MHz EPIRBs do contain the MMSI of the yacht. My reasons are that when I bought mine (McMurdo Smartfind) I just bought it. It came with a sheet of paper telling me the Hex code, and I duly filled out the EPIRB's form (now online, see https://forms.dft.gov.uk/mca-sar-epirb/#gf_240) which asked me for the Hex code. This Hex code was never changed or amended, and my identity, let alone my MMSI number, was unknown to the seller. I have just looked at the RNLI website for their explanation of an EPIRB which seems to bear this out

However on reading Roberto's helpful attachments, the country code is included in the bit-field, so that a UK message comes to the UK CG, and a Dutch message to the Dutch without having to go via an international database I surmise. And so I guess it's this bit the OP is keen to have amended - which may or may not be possible of course. So if the country code alone, rather than the full service identity can be termed the MMSI (which I wouldn't have thought it was), then I was wrong: but can MMSI really mean different things in different contexts?
Click to expand...

I had the same doubts about the MMSI then I asked Cospas Sarsat and they confirmed it is programmed into an epirb 15hex (of course, not in a PLB, which only has a country code and serial number).
Honestly, I see no point in trying to convince anyone "it is so", but just raising a doubt: if the OP is in doubt, just ask Cospas Sarsat and decide by yourself. :)

jdc,
I suspect (simple personal doubt), if the seller of your EPIRB has not asked you your MMSI, your beacon might be coded with a serial number instead of a MMSI (?).

If you have your 15hex handy, please do try and decode it on cospas sarsat web site:
https://www.cospas-sarsat.int/en/beacon-decode-program

and see if the country code and the MID number (your 6 remaining MMSI digits) come out or not, it might be interesting for everyone. The site decodes the 15hex *before* any declaration to the MMRC/Radio licensing authority is made; it is actually useful to check the MMSI has been correctly entered into a newly bought beacon, it is not unheard of beacons being delivered with the "manufacturer test 15hex" still programmed

There was an old thread about the same subject, I think it would be interesting for all if anyone having their 15hex tries to decode and check what the Cospas web site reports.

regards
r
 
All beacons, EPIRB or PLB, have a unique 15 character number. In addition, there is space in the system message to insert an MMSI. Some nations insist on this being filled by the vessel MMSI, others, including UK, do not. You can register your beacon with the MCA without inserting the MMSI into the beacon. However, the 15 character code is nation specific: the first digits identify the nation where the beacon is registered. If you have a beacon with another nations code in it, as the OP does, there are two options: register your details with that nation (If they permit this: did this with the U.S. Coast Guard) or send the beacon to an authorised dealer who will reprogramme the beacon with a UK code.
The UK authorities will accept beacon registrations from beacons which have been programmed with a vessel MMSI but there is no requirement to take this extra step.
 
Interesting thread. So much so that I dug out my yacht docs. file, which just happened to be here in the lounge (mine, that is).
I think Duncan has got it right, but I would like to add the following comments
Like many other Forumites, I purchased my EPIRB (McMurdo fastfind G5) from a well known UK supplier In 2009. Enclosed with it was a registration form to be completed and sent off to the MCA EPIRB Registry.
The form is pre-printed with:
Make of beacon
Name & address of manufacturer
Model
UNIQUE hexadecimal beacon identification code (thus a MMSI is NOT normally encoded)

Information to be entered on the form includes
Owners name and address
Emergency contacts
Details of vessel, MMSI, Call Sign, SSR no. etc.

There is no need for the MMSI to be programmed into your EPIRB. If you have registered it with those nice people down in Cornwall then MRCC Falmouth has your details including the MMSI in their computer. In the event that you activate your EPIRB their computer instantly links the received Hex ID to your stored details and all appear on their screens together.
I think I got that right- it is late.
Interestingly I also have the docs for my old EPIRB which I sold. That one had a HEX ID with digits 7,8,9 being the country code 235, presumably followed by the MMSI – 400001
Not sure about the MMSI because ours was changed arbitrarily in 2004 and we were sailing around with the wrong MMSI in our radio for a while…..:eek:

Michael.
 
Roberto said:
I had the same doubts about the MMSI then I asked Cospas Sarsat and they confirmed it is programmed into an epirb 15hex (of course, not in a PLB, which only has a country code and serial number). r
Click to expand...

I bought an EPIRB and registered it with the number on the EPIRB so knew that it could not contain my boat's MMSI. Much more likely that I'd win the lottery than manufacturer deciding to put my MMSI no. on that particular EPIRB. I don't even buy a ticket but always possible someone might randomly buy me one. :D

I did enter the code into decode program and that confirmed that the 15 Hex digit version of these codes only specify the country and have no reference to MMSI.

N.B. 22 and 30 Hex digit versions of the codes do have a country code and also trailing 6 digits of MMSI (i.e. numbers after country code).


Cospas Sarsat were obviously wrong when they confirmed it is programmed into an EPIRB 15 Hex number. Perhaps they were talking about the 22 or 30 digit versions. There is an unused 25 bit field at the start of the code and it could be used to hold a few characters or a big number but does not seem to be used.


EDIT: Just noticed earlier posts (Must remember to refresh pages before replying).
 
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Roberto said:
...

If you have your 15hex handy, please do try and decode it on cospas sarsat web site:
https://www.cospas-sarsat.int/en/beacon-decode-program

and see if the country code and the MID number (your 6 remaining MMSI digits) come out or not, it might be interesting for everyone. The site decodes the 15hex *before* any declaration to the MMRC/Radio licensing authority is made; it is actually useful to check the MMSI has been correctly entered into a newly bought beacon, it is not unheard of beacons being delivered with the "manufacturer test 15hex" still programmed
.../QUOTE]

Here it is.

Just country code. But that doesn't mean that other beacons wouldn't have more info.
Click to expand...
 

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I think that you'll find that the 'national use' field at 64 - 73 is where the MMSI can be programmed in if the national authority requires it. In the UK, as in the USA, this field is not required by the national authorities to be filled by an MMSI. Other countries do require you to have the MMSI entered into this field. If you want to, you can have the field completed for a UK registered beacon but there is no requirement to do so, as Falmouth has already crossed matched your MMSI with your beacon registration.
 
Good! thanks all for the replies and decoding the 15hex. :)
It appears the UK (possibly the US? I'd be grateful if any US users might try to decode their 15hex) are two countries allowing an epirb to be programmed with a serial number instead of an MMSI.

This is contrary to what is stipulated in the country specific agreements taken with Cospas Sarsat by the various countries (UK included), as shown in one of the links I posted earlier (the second one, a document roughly 300 pages long available on the internet, UK about page 200-201).
What is the reason I do not know, it surely makes things easier when changing boat.

I have not checked *all* the other countries, but most have two regimes, which correspond with the cospas sarsat regulations above
1. Epirbs, with the MMSI embedded in the 15hex
2. PLBs, where just a country code plus serial number is programmed into the beacon.
Quite often, there is a first Land Center treating all distress calls coming through satellite, dispatching them into "land" and "maritime" domains.

Also, per radio licence regulations, in many countries it is impossible to register a serial-registered beacon into a ship radio licence (a reference to MMSI or callsign is mandatory), whereas this appears possible in the UK.

So in the end it appears that beacons sold as Epirb in the UK have the technical specifications of Epirbs (temperature rating, battery, floating etc etc) but are often/always coded with a serial number.
A similar device would not be allowed into a ship radio licence in a lot of other countries.

UK%20epirb_zps3gd5mi4f.jpg




Whatever country readers are in, please do try and deode the 15hex to see what's inside the beacon
 
What EPIRB is? model?

You have to send it to a service to reprogram it, you have to send some information like the name of ship, call sign, serial number of the EPIRB, IMO number, Flag, the type of the hydrostatic release unit.

So they will generate the HEX number that it will be insert into the memory of the EPIRB.

Best regards!
 
A point maybe of relevance: 15 x hexadecimal digits = 60 bits (15 x 4). So any information contained in the data-field in bits greater than 60, eg 64 - 73, simply don't exist in the 15hex code. One would need an EPIRB which transmits a longer sequence - presumably different models rather than a just a country specific policy.

PS: There's a data management aspect. Why would it be good to have an MMSI in the transmitted sequence?

Good points:
- the data tells the ground station what the boat's MMSI is.
- It would allow the country of registration not to bother with an EPIRB registry per se (but I'm not at all sure that any country capable of having an MMSI administration process wouldn't have an EPIRB administration process as well).

Bad points:
- But a look-up in a computer data-base still has to be done: indexing by MMSI as opposed to indexing by EPIRB serial number seems of nugatory advantage.
- There is now an extra, manual and so error-prone, programming step in the acquisition of an EPIRB, adding cost as well. Mismatches are likley to occur, maybe 1% of times?
- If there's no EPIRB registry (see above) then an extra check against theft or malice has been eliminated.
- A longer data field implies more energy has to be transmitted per distress alert: higher because longer, and again higher because to receive a longer sequence without errors requires more Signal to Noise at the receiver so a more powerful output or longer error-correcting codes in the emitted signal. So slightly less reliable.
- If there's a mismatch - the EPIRB MMSI is yacht 'Flying Dutchman' but the EPIRB registration is 'Marie Celeste' - would that mean that no SAR is launched?

It's simply bad data management practice to store the same information twice in different and incompatible systems! But there again inefficiency and bad practice is the hallmark of government and bureaucracy! Think tax and benefit systems...
 
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Interesting that a simple question generates such debate. Especially as not included in VHF course/exam (should it have been?)
Just received, the 'official' reply from the Registry:

Unfortunately we are unable to register your McMurdo E3 beacon Hex: 9E88D64D41C70D1 as it is programmed with Dutch MMSI: 244020377. This beacon will need to reprogrammed either with your UK MMSI or using UK serialised protocol with Country Code 232. Once reprogrammed, please advise the new Hex ID in order for us to registry your beacon.

Seems pretty plain that the epirb itself needs to be reprogrammed.

Thanks to all for contributions.

Ron
 
For information, if your beacon is registered in the US, UK, Canada or Australia, the MMSI is not required to be programmed into the beacon, thus enabling simple re-registration when moving beacons between vessels. It would appear that all other nations require the MMSI or Callsign to be encoded onto the beacon, thus requiring that the dealer enter this information on purchase and any subsequent changes between vessels. This came from looking at the user manual for the beacon mentioned by the OP under the registration topic.
 
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