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post #27 of Old 12-03-2012
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Re: Follow the ARC

If it does not rely on land based observers, where does it get the information?-Matundscotbruch
Here is my e mail with the designer of the product. While he doesnt specificall say where the data is from, I had my droid phone on Marine Traffic which is land based and the positions were remarkably different on Marine Traffic from the Raymarine AIS and Boat Beacon which matched all the time.

> Does it really do AIS in real time unlike Marine Traffic.

The majority of our feeds are direct in real time from the AIS Receivers (over 70%). Our servers are handling over 20MB/s of data arriving. For instance in the UK around the Isle of Wight we get updates from the fast ferries every 2s and their updates appear in Boat Beacon within a second of being received.

All the other data is accurately time stamped at source and collated over 1 minute. On average this is only 30s behind real time and is displayed with the corrected time (and interpolated position) in Boat Beacon. You also have to remember that AIS transmissions from ships are sent at varying intervals from once every 3 minutes to every 2s depending on their status and speed. So for example a ship at Anchor can show a status that is 3 to 4 minutes old. Also the transmissions are not guaranteed and can be easily blocked by passing ships, bridges and island's etc.
I answered an ad on and was one of the first three to so I gt a promo number to download the ap for free. He asked that all I do is evaluate and write about my evaluatuations positive or negative whatever my finding were.

I downloaded it last Thursday on my IPAD 2. It can be downloaded on I or droids. Yesterday was my last day out on the boat till next spring and I tested it for about 4 hours. I have a AIS class A transponder hooked thourgh our Raymarine Chartplotter to c heck the accuracy of the Boat Beacon app.

In the 4 hours I ran them concurently they were identical. The Boat Beacon app has in its data a defined line which tells how lkong since the previous update. The longest was 2.5 minutes while most were updated in 30 seconds.

So far it looks good. I wont be doing more boat tests for a while.


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Last edited by chef2sail; 12-03-2012 at 09:40 AM.
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