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Wow.... I never knew those CDs that come in the mail with AOL's
passwords were trying to tell me _where_ to go to collect Bill Gate's
money for forwarding his emails to everyone in my address book!<br>
<br>
This is a neat idea ( it really piqued my interest) for sending, but
how would you put it into a GPS on the other end? 256 lines is an
awful lot of scrolling with a cursor key on your hand held GPS.
Seriously though, if you encoded with an interleave of lat lon lat1
lon1 lat2 lat2 , then if someone was close to me, chances are they
would have the same first four "words" as me in their position. So in
your example phrase 'monkey-bogus-walnut-rooftop-widget-badger', the
difference of a few miles might require on the alteration of the words
widget and badger. Now if you tried to create a waypoint in your
portable GPS for the other guy's location, the default location would
show "monkey bogus walnut rooftop widget badger" on the display, and so
I'd only have to select the last two words. Could be workable. Of
course there could be cases where you cross a major lat lon line,
(let's say you are 1m NW of 0,0, and I am 1m SE of 0,0) where we'd have
to use all 6 words.<br>
<br>
Since people can visualize words in their minds better than a random
sequence of numbers, garmin might be interested in this for hikers.<br>
<br>
Wes<br>
<br>
<a class="moz-txt-link-abbreviated" href="mailto:scott@opentrac.org">scott@opentrac.org</a> wrote:
<blockquote cite="midE1DbWdb-0006Xj-Eg@home.miller.org" type="cite">
<blockquote type="cite">
<pre wrap="">Do you also not support the ARRL's use of a standard Phonetic
alphabet? There are reasons that people involved in
comunicatinos like to have standards, it is to eliminate just
exactly the problem we have in HAM radio where not everyone
is using the DD MM.mmm... standard...
</pre>
</blockquote>
<pre wrap=""><!---->
Speaking of coordinates and phonetics, I got to thinking about that the
other day. A selection of 256 different two-syllable words could encode 8
bits per word. Six words would be enough to encode a position anywhere in
the world to within a few meters. You could do it in fewer words if you had
a larger selection, but it would get more difficult to find unambiguous
words. You could also add an internal check digit to make sure the position
phrase was valid.
Anyway, the idea was that your GPS would give you the phrase, and you'd read
it out over the air and someone could enter it into a computer to get your
position. That's usually what we're doing in the field, but it's more
tedious and error-prone with plain numbers.
It might sound a bit weird, though... "My position is
'monkey-bogus-walnut-rooftop-widget-badger'." Just a thought...
Scott
N1VG
And in case anyone's curious about the calculations:
Circumference of the Earth = 40,075,160 meters
24 bits each for latitude and longitude
40,075,160 / 2^24 =~ 2.388 meters
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</pre>
</blockquote>
<br>
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