[aprssig] APRS LAT/LONG standards
Steve Dimse
steve at dimse.com
Thu May 26 16:19:39 EDT 2005
On May 26, 2005, at 3:38 PM, Robert Bruninga wrote:
>>>> steve at dimse.com 5/26/2005 1:12:13 PM >>>
>>>>
>> findU uses decimal degrees, and will continue to do so.
>>
>
> Which is one of the biggest problems in APRS.
> There is no classical navigation system that uses
> decimal degrees for navigation. ANd it is not
> the APRS standard, nor the GPS standar and it
> only causes these kinds of problems.
>
> Why do you feel it is important to be out of step
> with the rest of the GPS world, APRS and all other
> classic systems of navigation?
Why do you feel that the way you do things is the way the rest of the
world does things?
Curt has already pointed out aircraft use decimal degrees.
APRSworld uses decimal degrees.
APRS+SA uses decimal degrees.
Steet Atlas uses decimal degrees.
Chicago Mapping uses decimal degrees.
MapBlast uses decimal degrees:
http://www.mapblast.com/(hm5scz4515qf3s55eb1rt32z)/map.aspx?
L=USA0409&C=25.79300%2c-80.20967&A=7.16667&P=|25.79300%2c-80.20967|1|
K4HG-8|L1|
Topozone uses decimal degrees
http://www.topozone.com/map.asp?lat=25.79300&lon=-80.20967&s=100&size=s
Acme mapper uses decimal degrees
http://www.acme.com/mapper/?
lat=25.79300&long=-80.20967&scale=10&theme=Image&width=3&height=2&dot=Ye
s
I do not know of a single internet service that uses degrees/minutes.
DD MM SS is a relic of a much earlier time, and likely persists to
the extent it does because 3 pairs of digits are easier to remember,
the DDMM.HH(HHHH) format is a hybrid relic of LORAN days. From a
computer point of view neither makes sense, decimal degrees convey
more precision in the same number of characters, and all calculations
involving lat/lon are muc heasier after they are converted to decimal.
So just because you disagree, do not put the blame on me. The rest of
the world is (gradually) adopting a standard that simply makes more
sense. Despite KC2MMI's assertion that decimal is "some newfangled
ISO standard" (when I first read this, I thought it was an
hysterically funny, sarcastic comment, only on re-reading I think he
maybe he actually meant it, either way I'm ROTFL), I'm pretty sure
decimal has been around longer than any of us have been alive ;-)
Steve K4HG
More information about the aprssig
mailing list