Xref: utzoo sci.physics:6133 comp.terminals:1149
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From: msb@sq.com (Mark Brader)
Date: Sun, 26-Feb-89 18:49:51 EST
Message-ID: <1989Feb26.184951.25637@sq.com>
Newsgroups: sci.physics,comp.terminals
Subject: Re: terminals in southern hemisphere
References: <1274@sri-arpa.ARPA> <6569@geac.UUCP> <420@unicom.UUCP> <1765@gmu90x.UUCP> <14882@cup.portal.com> <198@xpiinc.UU.NET>
Reply-To: msb@sq.com (Mark Brader)
Organization: SoftQuad Inc., Toronto

> Australia is very close
> to the magnetic south pole and the magnetic field there deviates
> significantly from the horizontal.  You would have a similar
> problem near the magnetic north pole.

Some quick computation gives the following rough figures:

	South Magnetic Pole to Melbourne	1900 miles
	South Magnetic Pole to Sydney		2200 miles
	
	North Magnetic Pole to Winnipeg		1800 miles
	North Magnetic Pole to Chicago		2350 miles
	North Magnetic Pole to Toronto		2350 miles
	North Magnetic Pole to New York		2500 miles

In other words, significant parts of North America *are* "near the
magnetic north pole"; therefore the problem would be particularly
bad if the terminals originated in those areas.

Actually, the magnetic dip angle doesn't vary in any simple fashion
with distance from the magnetic pole, but I don't have a map at hand
showing how whether the situation suggested by the above distances
is in fact true.  It's a reasonable first guess, though.

Mark Brader, Toronto	"If the standard says that [things] depend on the
utzoo!sq!msb		 phase of the moon, the programmer should be prepared
msb@sq.com		 to look out the window as necessary."  -- Chris Torek