Re: not long to go

boat.anchor <boat.anchor@...>

Now my head hurts

--- In, "melachri" <w3hf@...> wrote:

Mike -

Nice analysis. But I have one quibble.

Each sub-square, such as EL29hk is equal to 5 nautical miles by 2.5
nautical miles.
Did you intend this as an approximation, becuase that's not the way sub-squares are defined. They're based on latitude and longitude, not absolute distance. A sub-square is 2.5' (minutes) tall and 5' (minutes) wide. The height (in miles) of every square is the same because latitude lines are equi-spaced. But longitude lines converge at the poles. So at the equator, a sub-square is about 2.9 (statute) miles tall and 5.8 miles wide, but at 45 deg latitude, it's only 4.07 miles wide, and at the poles it's an isoceles triangle with height (still) 2.9 miles but with a width at the base of only 22 feet!

I think a better average width is 3.67 miles. (Derivation: Circumference is proportional to the cosign of latitude. Find the average circumference by integrating COS across latitudes from 0 to 90, resulting in (2/PI)*width at equator.) With a height of 2.9 miles, the average sub-square has an area of 10.575 sq miles, about 36% lower than your number. This scales your population density proportionately: 1216 people per sub-square, and 1.79 hams per sub-square.


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