If anyone's confused about what these maps would look like, I have some examples here: http://glaikit.org/2011/12/11/not-really-getting-the-azimuthal-equidistant-projection-right/
They were made with the not-exactly free AZ_PROJ, a utility written entirely in PostScript. For a great (but non-free) example of a grey line (day/night) map, see http://pskreporter.info Cheers Stewart On 2011-12-12, at 9:23, Colin McGregor <[email protected]> wrote: > Last Saturday I was at a party co-hosted by Richard Weait (thanks), > where the topic of maps for amateur radio use came up. > > A topic that has been of interest to me is amateur radio and disaster > response. > > So, I am looking for software that will generate two maps from Open > Street Map data: > > - An azimuthal equidistant projection map for any arbitrary latitude / > longitude > - A day and night map (ie: what parts of the world are CURRENTLY in > sunshine / darkness) > > So, what makes the requirement for the above a little tough? I want > the software to be under the GPL (or some other open license) so it > can be redistributed without issue. I want it for Linux (so the OS to > support the application can also be redistributed without issue). I > want the application to run stand-alone (so if there is a problem with > the internet connection I don't want the application to suddenly > become useless). The data for this can not be more than a few MB at > most (but then this shouldn't be an issue, given that road, rail, land > use data is irrelevant for these apps, all that is needed is > continental outlines, MAJOR lakes, rivers, islands and cities). > > So, why the interest in these maps? > > Many amateur radio antenna are directional (doing a better job of > receiving (or transmitting) a signal in one particular direction). > With an azimuthal equidistant projection map done for your location, > you can draw a line from the center of the map to the location you are > interested in and that will instantly tell you the direction to adjust > your directional antenna. This is static map, as in you generate the > map once for a given latitude / longitude you are effectively done. > > High frequency radio signals can refract off the ionosphere allowing > very long range communications with low power transmitters. What > frequencies refract well depends on a number factors, including > sunshine / darkness. So knowing that the place you want to talk to is > in darkness is useful. So, a day night map would have to be dynamic, > being updated say once per minute ... > > Anyone with ideas as to where I could / should turn for the above? > > Thanks. > > Colin McGregor > VE3ZAA > > _______________________________________________ > Talk-ca mailing list > [email protected] > http://lists.openstreetmap.org/listinfo/talk-ca _______________________________________________ Talk-ca mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk-ca
