MMSI number

harvey38

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The MOBO is already registered and has an MMSI assigned to the VHF onboard.

I have installed a DSC VHF to the newly acquired tender and the VHF requires an MMSI before it will operate.

Do I duplicate the main vessel MMSI or create a new one?

CheersRob
 
I asked the authorities about registering the dinghy and was told that a dinghy of our size, 2,5 m, is considered part of the mother ship, so I don’t need any additional registration. Tender To (TT) Nautic is sufficient. Perhaps the same applies to a portable radio in the dinghy, as we can’t stray very far from the mother ship with a 2.5 hp engine.

Stefan
 
AIUI If you have two fixed DSC VHF sets on the same vessel then that's the same MMSI. Portable is as Lucky Duck states, but if the tender has a fixed DSC VHF, then it needs a separate ships' radio licence. Name can be unique, or simply 'Tender to...' the mothership name.

Having said all that, I'd suggest you call Ofcom to check, they're really helpful.
 
If I had a tender that was small enough to have no registration of its own, and it had a fixed VHF like this, then I'd probably just program the tender's fixed VHF with a MMSI assigned as handheld registered to the ship. It might be technically prohibited, but you're not going to go to jail for it.
 
Lets look at the scenario that the 'red button' is pressed on the 'Dinghy VHF' which has the Mother Ship MMSI number in ...

Services will be looking for the Mother Ship - not the dinghy.

Anyone now thinking about that ??
Also will the mothership radio definitely respond as you'd expect to getting a DSC message from its own MMSI?
 
For Belgium if the tender is up to 2.5m then it is considered as a tender to the mother ship, and it can share the MMSI, however there is a range limitation of 500meters on the distance the tender can be from the mothership.
There is one licence issued for the boat with a common MMSI and ATIS code and that covers fixed and H/H VHF, MF, Radar, PLB, etc., VHF is only mandatory once your craft is 7.5m or longer or can travel at more than 20km/h.
 
The MOBO is already registered and has an MMSI assigned to the VHF onboard.

I have installed a DSC VHF to the newly acquired tender and the VHF requires an MMSI before it will operate.

Do I duplicate the main vessel MMSI or create a new one?

CheersRob
As others have said, definitely register the tender vhf as a separate device with its own MMSI if it has DSC. The important factor is that if you ever need to transmit a distress alert, the tender fixed VHF with DSC, just like any portable VHF with DSC, the emergency services will get confused locations and not know what they are looking for and that may delay your rescue. In this situation, the size of your tender is not relevant.
 
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If I had a tender that was small enough to have no registration of its own, and it had a fixed VHF like this, then I'd probably just program the tender's fixed VHF with a MMSI assigned as handheld registered to the ship. It might be technically prohibited, but you're not going to go to jail for it.
see post #17, if the tender VHF has DSC then it is in your own interest to register is seperately.
 
The facts are that a DSC portable requires registration to an individual and is given a separate MMSI from the portable category.
DSC Portable is a mess though.

The UK ignored international rules and started issuing Ship's Portable Radio Licences that were limited to UK territorial waters and handing out MMSIs for them.

Other countries add them to a Ships Radio Licence with an 8 prefix for the MMSI - only the 8 prefix is shared in the international directory.
 
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