Group calling – with DSC

Once you have a Group MMSI you can send an alert to all radios in that group.

Note that each vessel in your group we need to enter the group MMSI into their radio for this to work. See MMSI page to see how this is done.

The advantage of starting a group call by making a Group Alert is that once the alert is acknowledged it will retune all radios to the channel of your choice. It is a great way to catch peoples attention and get them listening.

On the Icom a Group Alert is sent in the following way:

From the start screen:

– Press “Menu”
– Scroll using the ARROWS to Group Call
– Press “Enter”

If the Group MMSI is in your “phone book”

If the Group MMSI is not in you “phone book”

 – Scroll using the ARROWS to the name of the group you wish to call.  – Scroll using the ARROWS to Manual Input
– Press “Enter”
 – Press “Enter”  – Enter the MMSI number using the ARROWS to select the number and CH button to move to the right and 16 button to move to the left.
 – Press “Enter”

– Scroll using the ARROWS to the working channel you wish to call the group on.
– Press “Enter”
– Press “Enter” again to confirm – the Alert has been sent.

Don’t wait for an acknowledgement (you will not receive one), but wait long enough for people to get to their radios and respond by excepting your call.

At this point your radio and all radios that have excepted your call will change automatically to the working channel. You then start you voice call on the working channel – YOU talk first!

From this point on the voice communication is undertaken in the same way as without DSC. See the Calling without DSC page for more details.


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