-Collision Avoidance Radar Detector--as a single hander wanting to sleep I relied on this to at least help avoid a collision with a freighter at sea. It worked very well. One night there was a ship which definitely did not have its radar on and it also did not answer any VHF calls but for all others I received a loud alarm when ships were within about 5 miles on average. Plenty of time to take action. It gives quite a few false alarms but after a lot of thinking I boiled this down to two reasons. Airplanes first. It just made sense that aircraft using radar would be picked up since they certainly are in range albeit vertical instead of horizontal. Secondly, I think there is some sort of freak emission at sunset since the