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post #72 of Old 11-27-2012
MarkofSeaLife
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Re: Do I Need an EPIRB?

Quote:
Originally Posted by CarbonSink62 View Post
I know it is well over the horizon; my Navy training said that the horizon is 9 mi away if you are six feet off the water. My antenna is 33 feet off the water.

I took a stab at 20 miles; how far off am I?

Ken
Actually very close but you forgot to add the height of the receiving antenna. And I don't think your Coast Guard worried about how many tax payer dollars they spent. I think the got big ones.

If the CG tower is 200 feet high add your 33 feet and its 18 nms to the horizon. But by that time even VHF can bend a bit so it's longer.

If the CG tower is on a hill so it's 433 feet then that's 25 nms

But my AIS picks digital up regularly at 40nm and sometimes up to 100nms on a 53 ft mast

Anyone know how tall the CG towers are?


Mark

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Last edited by MarkofSeaLife; 11-27-2012 at 12:26 PM.
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