Facebook APRS integration

Today I released the Facebook aprs.fi map application. If you're on Facebook, you can use the application to show the position of your APRS tracker / vehicle on your profile page. Yes, you need to sign up on Facebook to get a glimpse of it. Sorry about that.

The map is somewhat configurable, supports several different map types, zooming, different measurement units and coordinate formats. It runs on the same quick and scalable backend servers with aprs.fi.

There are some issues with the combination of Google Static Maps and Facebook, so it might stop working once it becomes a bit more popular. We'll see later.

I'm sure a lot of you will shake your heads in disbelief, and quietly comment something about the uselessness of this feature, but let's face it, Facebook is a big thing, and I just wanted to try it out, see what's going on in there, and figure out how things can be integrated with it.

aprs.fi also has a facebook page now. I don't know what it's good for, but at least you can mark yourself as a fan of the site to show your support. And maybe exchange some related photos, links and videos there, or use the discussion board. I'm sure it has a better discussion board feature than this blog's comments.

Slovene / slovenščina translation completed

Thanks to S53TK, S55M, S56G and hihi, there's now an almost complete Slovene version of aprs.fi! Thank you!

Technical details: what's behind the scenes

Some of you might be interested in knowing what aprs.fi runs on top of, so here's some technical information about the technology, design and implementation of my little APRS site.

Ruler and reverse geocoding

While I'm up to speed, here are a few more late Christmas presents!

There's a new ruler tool, which is enabled using the compass icon, which can now be found just below the PHG circle icon. The ruler calculates great circle distance and direction between two points. Multiple rulers can be added by clicking on the compass icon again. Clicking on a ruler endpoint marker will reveal the coordinates and address of the marker position.

Furthermore, after clicking on any target on the map, an address will be shown, if possible. The address is obtained using Google's reverse geocoding service. The service may or may not be available in your area, and the data is received with a small delay after the info balloon is first opened.

Improved panning speed

I've just added javascript code to delete path points which are out of the current view. This reduces browser memory leakage and speeds things up considerably when browsing around the real-time APRS map. You'll notice this when panning away from and area, and then back - it'll take a couple of seconds to reload the map points from the server.

PHG antenna direction plotting

Last night I figured out the math to plot nice cardioid patterns, and this morning I finally got the rotation right, so now the PHG plotting shows the directivity parameter, too. It's been requested by quite a few users since I got the circles going.

The first image shows a PHG plot with an omni pattern (no directivity), and the second image shows a PHG plot with a directional antenna pointing at 135° (southeast). Please bear in mind that these plots describe very rough approximations and best guesses about the station's service range.



You can generate a PHGR comment extension for your digipeater or igate using the PHG calculator. Please monitor your station's receiver performance and adjust the PHG settings to match the observed range.

iPhone and iPod Touch fixes

Google has recently fixed a couple of bugs in the Google Maps API code, and both map controls and events have suddenly started working using the iPhone web browser. I've put them back in now, and the real-time APRS map is suddenly much more functional. Thanks for the little Christmas present, Google!

Look for me on HF digital modes during the Christmas holidays, I'm trying to be active from a few countryside locations.