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Old 09-02-2019, 11:07 PM   #10
dhays
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City: Gig Harbor
Vessel Name: Kinship
Vessel Model: North Pacific 43
Join Date: May 2015
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Quote:
Originally Posted by Wayfarer View Post
I think a lot of people think that the information on both machines is the same, but it's not. Each piece of equipment comes up with it's information from different methods. The radar actually tracks that echo that you see on the screen, and does the plotting math for you, based on what it 'sees.' The AIS uses the data it receives from the target, as well as the data from your gps to calculate CPA.
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Great reminder. If I recall, Class B transceivers only send out information every 30 seconds. 30 seconds is a very long time when two boats are converging. Not sure what the frequency is of the Radar scans but I think it is a lot more frequent than that.
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