Join Date: Mar 2006
Location: New England
Thanked 16 Times in 13 Posts
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A problem I've seen is that some people mistake the icon on the chartplotter screen for their position in the real world... it isn't. It is an electronic representation of a location of a physical boat on a probably inaccurate rendition or interpretation of the real world by a cartographer, often using data that is decades old. In many cases, it is good enough to prevent disaster, but there are places where the cartography and the real world don't even come close.
I've seen few situations where the GPS couldn't keep signal lock in torrential rain, and believe that the GPS signal, which uses just a 50 Watt transmitter IIRC, can be attenuated by water as is the case with most other radio signals. However, I get the feeling that fog would have to be exceptionally dense and high-reaching to attenuate the signal that much.
Of course, there are other factors involved... was his GPS being used inside the cabin with an integrated antenna? Was it a parallel channel, multiplexed receiver or a single channel receiver? Was it a shipboard unit with an external antenna? Were his batteries fresh? Etc...
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You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.
—Cpt. Mal Reynolds, Serenity (edited)
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