Talk:Maidenhead Locator System

Maidenhead lower case letters

The article suggests that the final 2 digits of a six digit locator are usually given in the USA and UK in lower case. Most amateurs in the UK in fact use upper case exclusively and I have never seen lower case in use over here. I wonder where the information came from? I see it was first added by User:Kharker on June 5th 2006 and the UK bit added later.Dsergeant 19:27, 27 August 2006 (UTC)

ARRL and AMSAT both use small letters for the third coordinate. ›mysid (☎✎) 10:58, 22 July 2012 (UTC)

They should all be Upper Case as per the IARU Region-1 intention

• a) to prevent confusion with the old system
• b) To ease extensions to 8 and 10 digits — Preceding unsigned comment added by Mjnmjn (talk • contribs) 20:33, 26 February 2017 (UTC)

"Hack"?

I believe the term "hack" in the sentence "Many utilities exist to convert latitude and longitude to locators, as this is a favorite hack for programmers who are also radio amateurs" is used incorrectly. the use of the word "hack" in this sentence makes the process of converting Longitude and Latitude into a Maindenhead Locator seem wrong or like something that shouldn't be done. i propose changing the word "hack" for trick or thing.
Mvm92 (talk) 02:30, 29 February 2008 (UTC)

Perl code

Thanks for adding the perl code to the article. Here is another version that I find to be more compact and easier to understand:

#!/usr/bin/perl -w
# (c) 2012 Chris Ruvolo.  Licensed under a 2-clause BSD license.
if($#ARGV < 1){
  printf("Usage: $0 <lat> <long>\n");
  exit(1);
}

my $lat = $ARGV[0];
my $lon = $ARGV[1];
my $grid = "";
  
$lon = $lon + 180;
$lat = $lat + 90;

$grid .= chr(ord('A') + int($lon / 20));
$grid .= chr(ord('A') + int($lat / 10));
$grid .= chr(ord('0') + int(($lon % 20)/2));
$grid .= chr(ord('0') + int(($lat % 10)/1));
$grid .= chr(ord('a') + int(($lon - (int($lon/2)*2)) / (5/60)));
$grid .= chr(ord('a') + int(($lat - (int($lat/1)*1)) / (2.5/60)));

print "$grid\n";

And code for making the reverse calculation:

#!/usr/bin/perl -w
# (c) 2012 Chris Ruvolo.  Licensed under a 2-clause BSD license.
if($#ARGV < 0){
  printf("Usage: $0 <grid>\n");
  exit(1);
}

my @grid = split (//, uc($ARGV[0]));

$lon = ((ord($grid[0]) - ord('A')) * 20) - 180;
$lat = ((ord($grid[1]) - ord('A')) * 10) - 90;
$lon += ((ord($grid[2]) - ord('0')) * 2);
$lat += ((ord($grid[3]) - ord('0')) * 1);

my $formatter;

if ($#grid >= 5) {
  # have subsquares
  $lon += ((ord($grid[4])) - ord('A')) * (5/60);
  $lat += ((ord($grid[5])) - ord('A')) * (2.5/60);
  # move to center of subsquare
  $lon += (2.5/60);
  $lat += (1.25/60);
  # not too precise
  $formatter = "%.5f";
} else {
  # move to center of square
  $lon += 1;
  $lat += 0.5;
  # even less precise
  $formatter = "%.1f";
}

$lat = sprintf($formatter, $lat);
$lon = sprintf($formatter, $lon);

print "$lat $lon\n";

If you guys think it is appropriate, please feel free to add it to the article. --ChrisRuvolo (t) 17:52, 13 September 2012 (UTC)

Hi Chris, if these scripts are yours and you agree to release them under a free license (GPL etc), I agree to add them in the article. Could you please add the appropriate info in comment lines, so that they are not deleted later by an over-zealous copyright activist? SV1XV (talk) 18:45, 13 September 2012 (UTC)

Yup, they are mine that I made based on the description of the system. I've put in a copyright statement and an indication of a 2-clause BSD license, which is just about the most liberal license available. Feel free to use one or both for any purpose. Cheers. --ChrisRuvolo (t) 20:03, 13 September 2012 (UTC)

Fine, I added both of them in the article. Thank you! SV1XV (talk) 20:09, 13 September 2012 (UTC)

Promotion to C class

The article now contains acceptable references and supporting material, I promoted it to C class for WikiProject Amateur radio. SV1XV (talk) 08:43, 15 September 2012 (UTC)

History, Distance, DX Contesting

The "History" section begins, "DX contesting is scored based on the distance of contacts, typically 1 point per kilometre...", and is attributed to a web page. There are a few issues here. First, the web article cited does not specifically refer to "DX contesting." Rather, it mentions contesting in central Europe, which does not satisfy the customary definition of "DX" used in that region, namely, an inter-continental contact. Further, the most prominent DX contests, such as the CQ Worldwide (often the largest, in terms of total QSOs), Russian DX, and ARRL DX, do not score based on distance. As written, the sentence is incorrect. I have edited it to conform to what appears in the cited source. 2604:6000:1011:ABE:A192:8C0:E0C1:AFC8 (talk) 13:05, 22 July 2020 (UTC)

no maidenhead info anywhere on page

When I click on the grid square for ARRL HQ it takes me a page with lots of info but nowhere does it actually show the maidenhead grid square designation for the given location. This seems pretty strange to me.

Ecdowney (talk) 21:23, 31 July 2021 (UTC)