i sail on two boats with the zeus - as i mentioned above, they are a few years old, from the first year they came out.
neither one displays the name of an AIS target - only the MMSI number.
is there a setting for this? I couldn't find anything...
I too wondered at this. Until I learned that Class AIS units do not transmit such info very often: Once each 6 minutes (at best). Not only that, but for other messages the transmission frequency is dependent on the speed and rate of turn of the vessel transmitting! It makes sense. Having said all that it might be possible that older units never send the vessel name. I don't know that. My Zeus does display vessel names, but when a contact is first acquired it appears as the MMSI number, only to be replaced by vessel name after a while.
Here's some info I have found about the message that contains the vessel name... Notice the note regarding firmware upgrades to be able to decode this message...
Message 24: Class B CS Static Data Report
This message is sent every 6 minutes, the same time interval as for Class A transponders. Because of its length, this message is
divided into two parts, sent within one minute of each other. Note that this message was defined after the original AIS specifications,
so some Class A units may need a firmware upgrade to be able to decode this message.
MMSI, boat name, ship type, call sign, dimensions, and equipment vendor id.
AIS data is transmitted at following intervals:
Dynamic - Position, Time, SOG (Speed Over Ground), COG (Course Over Ground), Heading, Navigational Status, ROT (Rate Of Turn) At anchor/moored - 3 minutes
<14 knots - 10 seconds
<14 knots and changing course - 3.3 seconds
14-23 knots - 6 seconds
14-23 knots and changing course - 2 seconds
>23 knots - 2 seconds
>23 knots and changing course - 2 seconds
Static - 6 minutes
Dynamic - Position, Time, SOG, COG
<2 knots - 3 minutes
>2 knots - 30 seconds
Static - 6 minutes