Sunday, October 28, 2007

New view: moving targets

Just a few minutes ago I published links to a new page: http://aprs.fi/moving/ shows APRS and AIS targets which have moved within the last 5 minutes. It's an easy way to find a "live" tracking target. And some drifting stations, which in reality are very much fixed and non-movable.

Today I also did some work trying to speed up the generation of the info pages. They do a lot of database lookups and feel a little bit slow. Managed to optimize the nearest cities lookup by about 200 milliseconds, which is very much noticeable. It probably cannot be optimized much more (other than by adding faster hardware, or by removing information from the page).

Also had a few contacts in the CQ WW SSB contest, and submitted my JARTS RTTY contest log. And visited the OH2RCH site in Juhanila, powered up the igate Linux PC which had been down for a week.

Thursday, October 25, 2007

aprs.he.fi and gaprs.net are now aprs.fi

A week ago Justin McAllister (K5EM) emailed me asking if I had any interest in taking over the gaprs.net domain, since lately he's been forwarding users with feature requests to aprs.he.fi anyway. The ownership of the domain has now been transferred and pointed to my site (although it might take until tomorrow before all DNS caches have obtained the new IP address). Thank you for the support and donation, Justin!

To make the site's URL even shorter and easier to remember, I've also obtained aprs.fi and pointed aprs.he.fi to it. That's only 7 characters to spell and remember. Old links will continue to work for the foreseeable future. The downside is that browser cookies don't work over domains, so you'll need to log in and set up the options again. Sorry about that!

So: the new "official" link is aprs.fi.

Gaprs.net and aprs.he.fi links will continue to work as before.

As I am writing this, the site is running on batteries (they're testing the UPS batteries, and after that, the diesel generator).

Monday, October 22, 2007

Character set fixes and invisible enhancements

Today I fixed most of the 文字化け issues. 乱码, 亂碼, маймуница and крокозя́бры should be gone, too. If you don't know what that means, they didn't affect you. If you still want to know, look it up on Google. 8)

No, you cannot search Japanese callsigns from aprs.he.fi, but at least trying to do so will now give a nice error message instead of letting the database say "no, you cannot compare apples with oranges" (in technical terms, of course).

Over the weekend and most of last week I also did a lot of fixing and restructuring which is not too visible right now, but supports wider localization of the service. Awful lot of rather boring and mechanical work, moving a lot of code and strings around, testing, fixing, testing, then moving some more. But it needed to be done eventually.

Localization issues are a new interesting frontier for me. Remembering the times when Finnish special characters (åäö) were rendered incorrectly more often than not, it hasn't yet stopped to amaze me how those Asian characters can "just work" on modern Linux systems, and how my web apps can be fixed to support them with so little work.

Thursday, October 18, 2007

Ships in Åbo and the ARBONET-II balloon launch

Thanks to www.aboais.net, we now have an AIS feed from Turku, showing the busy traffic of the Archipelago of Finland (Saaristomeri). Thank you, Petri!

Mark, N4CMB reports that the ARBONET team is launching a high-altitude balloon called ARBONET-II from JD Trissell Airport in Clarksville, Texas at 14:30 UTC (9:30 AM CDT) on Saturday, October 20th. The balloon will carry an APRS tracker operating on 144.390 as K5FRC-11 (aprs.he.fi tracking), a 70 cm up / 2 meter down cross band FM repeater, a 10 meter CW beacon and a plain language homing beacon that will transmit navigation data in plain English on the 2 meter band. There are cameras and environmental sensors too, so there should be some fine coverage of the event afterwards!

Monday, October 15, 2007

New web frontend server

The main aprs.he.fi server was feeling a bit sluggish - it was starting to run out of memory, and it did some swapping. This happened simply because there are so many people looking at the maps at the same time, and fetching real-time updates from the server at a rather high constant rate. So today I separated the web server to another server, and left the database running on the old server computer. This seems to help the situation quite a lot, and did not require a lot of work.

There was a very short outage caused by the change - by accident the new frontend server did not serve your requests for a couple minutes, since I had accidentally forgotten an access list in it's configuration. It only worked for me! Sorry about that.

Maybe in the future I'll try to put together a couple of dedicated frontend servers and start load-sharing web requests between them. Adding a slave database server would make the HA setup almost completely fail-safe. The software I've written seems to support scaling to a cluster with multiple servers just fine. I had hoped it would, since it was designed to, but I didn't try it until now.

Sunday, October 14, 2007

Finnish translation and more graphs

I spent almost all of saturday with my favorite text editor joe, working on these two gems.

You can now click on show graphs in the info view of a station, and get some plots on the activity of the station. The number of graphs will depend on the type of the station - if it is an igate, a digipeater, or a moving vehicle. For example, take a look at
http://aprs.he.fi/info/graphs/OH2RCH (a good local rx-only igate)!

While doing this, I enhanced the graph plotting code to do bar graphs, and to scale X better than before (filling the whole range). And added URL watermarks. These enhancements benefit the weather graphs, too.

The other big item was translating the user interface almost completely to Finnish. Language selection is based on your browser preferences (Explorer: Tools / Internet Options / Appearance: Languages, Firefox: Edit / Preferences / Advanced / General / Languages: Choose). These browser settings define the default language of most well-behaving international sites.

The weather page has mobile templates now, too, so it should look better on your phone.

Thursday, October 11, 2007

AIS from Trondheim, and lost raw packets

We now have AIS from Trondheim, Norway, thanks to Tomas Roald!

I just installed an improved database schema for raw packets, making callsign lookups for raw packets much quicker. Storing twice as much as data as before (actually storing everything twice), but retrieval is over twice as fast. I deleted the two days of history, I hope you won't mind (after 48 hours, you shouldn't).

Tuesday, October 2, 2007

APRS in a rally car

Kris (KI6IUC) reports that they'll have APRS tracking in their rally car while driving the Prescott Rally in Prescott, AZ, USA on Friday and Saturday this weekend. Cool!