What is on the "RADAR" screen?

The "Radar" screen (as it is often referred) provides the user with a basic overview of the location of AIS targets in relation to their own vessel.

The "No Heading" message stays on the Radar screen as it is a safety feature to remind the user that it does not indicate a true heading, rather it is a North Up "NRT UP".  When/If the user attaches a heading sensor to the unit then the phrase "HDG UP" will appear in the top left hand corner and the "NO HEADING" message goes away.