VHF alarm

Cathy*

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Can anyone answer this for me please?

We were out in Plymouth Sound the other day when we heard an alarm on the VHF. On the screen it said 'All Ships' It wasn't followed by any kind of message. We had the option to mute or cancel so we cancelled. This has happened a couple of times before. I don't remember hearing about this on the radio course and there's nothing in our Raymarine manual. What does it mean?
 

ex-Gladys

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With DSC, the "data" part of the transmission can operate usably over a greater distance than the speech. I've had this DSC calling another vessel where we can both "set up" the call, but can't hear each other due to distance
 

Cathy*

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With DSC, the "data" part of the transmission can operate usably over a greater distance than the speech. I've had this DSC calling another vessel where we can both "set up" the call, but can't hear each other due to distance

Thanks. I've also had an answer from an RNLI volunteer:-

'It is a call from a vessel which has broken down, or poses a safety risk to other vessels for some reason. The procedure is for the vessel in trouble to broadcast the "All Ships" message automatically on Ch70 DSC which then appears on the screen of other DSC radios in range. The senders radio should then automatically re-tune to Ch16 and the sender should broadcast a securite message describing the problem. If you didn't hear a securite message. The "All Ships" broadcast was probably made in error or the sender didn't know how to follow it up (More likely).'

Together with your answer that gives me 2 possibilities. Either way we didn't do anything wrong by cancelling it.
 

lpdsn

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Thanks. I've also had an answer from an RNLI volunteer:-

'It is a call from a vessel which has broken down, or poses a safety risk to other vessels for some reason. The procedure is for the vessel in trouble to broadcast the "All Ships" message automatically on Ch70 DSC which then appears on the screen of other DSC radios in range. The senders radio should then automatically re-tune to Ch16 and the sender should broadcast a securite message describing the problem. If you didn't hear a securite message. The "All Ships" broadcast was probably made in error or the sender didn't know how to follow it up (More likely).'

Together with your answer that gives me 2 possibilities. Either way we didn't do anything wrong by cancelling it.

Can also be something as simple as a weather report with the Coastguard sending out a DSC all ships beforehand. Solent Coastguard used to do it for a while, but I think they've now stopped. Certainly the UK Coastguard stations around the Irish Sea & W Coast of Scotland don't do it now, but the Irish Coastguard still do (still irritating when they pick their moment).
 
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