[Xastir] MGRS/Maidenhead grid squares.

[Curt, WE7U]

On Sat, 8 Jan 2005, Tapio Sokura wrote:

> James Ewen wrote:
> > The grid lines fall exactly where they should to outline the Maidenhead grid
> > squares...
>
> I just noticed that the Maidenhead grid calculation in Xastir is
> slightly incorrect. For example when I zoom close to 60N/20E crossing
> the status line says 20E, 59 deg 59.983 min N is already KP00AA, but it
> should be KO09AX right upto 59 deg 59.999 minutes N (the change happens
> between 59.982 and 59.983). This seems to be visible on any south-north
> maidenhead border, the change happens 0.017 minutes too soon (use zoom
> level 1).
>
> East-west direction calculation seems to be ok, the change happens right
> at the degree border.

Does it also have the same error using the Map->Coordinate
Calculator?  I'm getting JO99xx with 59.999N/20E, and KP00aa with
60N/20E.  The first one doesn't jive with your data above.

It looks like there might be two sections of code in Xastir that do
the Maidenhead calculation.  At least it doesn't look like the
Coordinate Calc version of code is used to update the "text2"
widget on the status line, so there must be more code to do that
part.

--
Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
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