Hi everybody...
Preamble
First of all I am not trying to start a useless polemic... because as mentionned
in each of my mail on the topic, it does not really matter...
Second preamble (I have to be very careful!)
I am not a geograph, or a mathematicien...
BUT..
I am curious, and a bit player... (otherwise I wouldn't be a contester...)
So I wanted to find the reason why the distance calculation did not match
between N1MM and the DK3VN calculator...
On one side PA1M (from N1MM team) wrote me that they had checked their distance
calculation against other popular VHF loggers, like TAC-log, and that
they were in agreement... Writelog users also confirmed on 3830 that WL calc was
also below the online calc.
On my side also did some testings with VQ-log with DX-atlas and finaly with my
Garmin GPS - all confirmed that the N1MM calculation was correct...
So I went back to Waldemar's formula and again it seemed to be correct - for
example the antipodal point of my square JN35AU being AE34AD (somewhere near
Pitcairn Island!) was calculated as 20,038kms which is exactly PI*R(20037.5805)
So what was wrong...
It could not be PI - so it had to be R !
As mentionned on its page DK3VN is using 6378.16kms as radius for the earth.
Like my GPS does, the concensus seems to use the WGS84 "mean radius" (6371 kms)
and not the equatorial radius 6378.1 kms...
That's it !
Now as there is more than one "mean value", the discussion could continue for
ever, but as mentionned in the preamble I am not a specialist...
Once again just for the fun and my curiosity...
(In any case it won't impact the contest results...)
Best regards - Patrick
You can follow those references if you are interested:
http://home.online.no/~sigurdhu/WGS84_Eng.html
http://ssd.jpl.nasa.gov/phys_props_earth.html
===========================================================
[RTTY] Makrothen & Claimed Scores
from [Waldemar DK3VN] [Permanent Link][Original]
To: RTTY Contest <rtty@contesting.com>
Subject: [RTTY] Makrothen & Claimed Scores
From: Waldemar DK3VN <dk3vn@nexgo.de>
Date: Tue, 12 Oct 2004 00:26:49 +0200
List-post: <mailto:rtty@contesting.com>
Hi,
if your contest logging software package does not provide your claimed
score or put out your claimed score without any band weighting, then
see the page "Calculation Claimed Scores" on the Makrothen (TMC)
web site. There you can copy your whole Cabrillo log in a form.
One click and after a few seconds you know it. Please have in your
mind, there is no log checking, no dupe checking, etc..
You don't have to re-send your log, because you have not provided any
claimed scores! Providing your claimed scores is voluntary, but desired,
of course. If you want your (re-calculated) claimed scores should show up
on the RWRL & TMC web site without (re-) posting them on the 3830 form,
then you can send your Info to me via email:
Call, QSO's, Score, Category, Operating Time
Where is the center of a Maidenhead square (i.e. EM84)? In the center of
a square you have four sub squares.
square center line
|
+----+----+
| LM | MM | <- this sub square is i.e. EM84MM
square center line --+----+----+--
| LL | ML |
+----+----+
|
In my calculations I am using the lower left corner of the
MM sub square as the center of a square. ~:)
If you want to see the source code, just go to the web page
"Calculation Claimed Scores" and click with the right mouse button
on the green area. A little window will po up and then click on
".. source code ..".
Now it's past midnight and time to go to bed. ~:)
73 de Waldemar, DK3VN
--
Check RWRL http://home.arcor.de/waldemar.kebsch/
or the Mirror http://www.qsl.net/dk3vn/
TMC http://home.arcor.de/waldemar.kebsch/The_Makrothen_Contest/
or the Mirror http://www.qsl.net/dk3vn/The_Makrothen_Contest/
German DX Foundation #207 http://www.gdxf.de/
Big antennas, high in the sky, are better than small ones, low!
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