Talk:Digital selective calling

Deleted confusion with AIS
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 * A British company NASA (no relation to the National Aeronautics and Space Agency) have produced a "radar" which is ideal for sailing boats (the #1 worry is that of being run down by a container ship) The unit plots the trajectories of all ships within range and alarms can be set if any ships get into the danger zone. The unit has low power consumption and costs about half the cost of the usual analogue radar detector that has very limited usefulness. It is extremely useful to be able to see the ships name, speed and course and the writer regards this marriage of GPS and VHF radio as a tremendous breakthrough. Admittedly this "radar" does rely on the big ships having their beacons switched on but they are obliged to do this by law. I have no connections to the company NASA apart from being a satisfied customer.

I have deleted it from the article, but I leave it here in case it is of use. Gaius Cornelius (talk) 10:54, 13 October 2011 (UTC)


 * Not a great deal of use, as the no-doubt well-intentioned author seems to have mixed up DSC and AIS :-) 195.212.29.94 (talk) 13:19, 5 August 2013 (UTC)
 * There are plenty of economical small vessel AIS receivers. Only a few manufactures such as NASA market it with a confusion to radar!Billlion (talk) 17:31, 14 April 2019 (UTC)

Multi-frequency acknowledgement
The text from the article "As the distress message can only be sent on one of the bands," reads to me as if it should read "As the acknowledgement message can only be sent on one of the bands," Unfortunately I haven't got any suitable references to hand to check this so have avoided editing, if anyone can double check and edit that would be great. Thanks. --Alistairbell (talk) 21:06, 13 April 2019 (UTC)