Last updated: 20090926Automatic Packet/Position Reporting System was developed by Bob Bruninga, WB4APR, for tracking and digital communications with mobile GPS equipped stations with a two-way radio (check out the APRS Wiki).
Where am I? (work most likely)
I was asked to do an APRS introduction at the 2009 TAPR DCC. So I updated the previous slidesets and it is available here ( about 2.7MB pdf).
I also wrote an article (An Introduction to APRS) for the IRTS's "Echo Ireland" newsletter in an attempt to make some of the ideas in the slides a bit clearer. A PDF of the article is available here, and a further article on some of the more advanced features is available here
Before try anything on APRS, please read this first.
Some good places to start gathering information are WB4APR's homepage at aprs.org, the APRS Wiki, AJ3U's tips on using the TM-D700, and aprs.fi OH7LZB's Google map based tracking. Have a look at Stephen, WA8MLF's page on HF APRS.
Have you read it yet?
Kenwood TM-D710 users, check your user manuals on section APRS-13. There's also a section on Voice Alert.
Note: If you don't have a radio like the Kenwood D7/D700/D710 (capable of putting Tx/Rx CTCSS code squelch on APRS packets), you can still utilize the Voice Alert concept. Simply add the APRS frequency (144.800 MHz in Europe) with 136.5t CTCSS Tx/Rx frequency to your list of scan channels and then you will only hear any APRS packets sent with the same CTCSS tone frequency. Naturally, in this case you won't be able to decode the APRS packets, but you will know that someone is within range of having a simplex QSO.
Simply invite the other party to a 2m simplex channel as described in WB4APR's instructions. Remember to Tx with the same CTCSS code, otherwise the other party's squelch will not open.
Hint: As WB4APR mentioned in his instructions, the fact you are transmitting APRS packets with a CTCSS tone means you are there to answer Voice Alerts. If you want to transmit APRS packets when away from the rig then do so, but without the CTCSS tone. An easy way to do this is to utilize two memory channels and switch between them as necessary:
At a recent AREN event I used it to call Francis, EI5GOB. I was out of range of the SERN repeater system, I heard a Voice Alert packet, looked at the display, spotted it was Francis, EI5GOB and quickly passed a message to him, we also agreed a simplex channel to work him on until I got back in range of the repeater system.
OH1UK bullied me into doing this section on Voice Alert
At the moment the main part of the infrastructure is maintained by the South Eastern Amateur Radio Group and it consists of the nodes:
The APRS-IS is an Internet-based backbone network which interconnects APRS radio networks. The core network consists of three (two now?) first-tier servers and numerous second-tier servers, providing a unified worldwide APRS stream to connected clients.
Purely for practical reasons (aggregation), not political ones, I maintain a Tier 2 server ireland.aprs2.net, which allows Irish APRS Internet Clients a common aggregation point.
The easiest way to gain access would be to configure your APRS client to connect to
ireland.aprs2.net with the port set to
Here are some maps made available courtsey of Tim, EI8IC. I added the .inf and .geo files in order that Xastir and UI-VIEW can use them.
I have also generated a (9MB) map of the entire country, with a geo and inf, and the South East (also 9MB) with a geo and inf files.