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Old 03-05-2006, 12:53 AM   #87
Skipper of the Sea Que
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Question The North Pole is where Santa lives

Quote:
Originally Posted by Misty Blue
But which way is north?

New question: When you look at the MAGNETIC compass in your boat it may not be reading truely north. There are two things causing errors in it's reading. What are they?
Let's see if I can get this one. The magnetic compass does not point to true north. Magnetic variation changes depending on where you and your compass are. Magnetic North also moves at a pace of about 10km a year. It's where the magnetic field is and that does not coincide with True North. So, the magnetic compass will (usually) point to Magnetic North which is NOT the same as TRUE North. I recall an old formula for converting, TV=MDC...or something like that.

Then there is magnetic deviation. Almost anything metallic on your boat can influence your compass needle. The motor, wiring, other metal can all make a difference and possibly cause false readings.

Some compasses have little adjustments you can make to compensate for magnetic variation. Some people have placed small magnets strategically around their compass to even out irregularities from metal in the boat.

I don't have a compass mounted on my boat anymore. They kept breaking and, after several units and an expired warranty, I gave up on it. Besides, to use it you often need to know where you are and where you are going. If I already know that then why do I need the compass ?

Did I come close Misty?
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