APRS (Automatc Packet Reporting System) is a system that transmits your location using RF and/or internet. It started out using AX25 “Packet” beacons to transmit information on your speed, postition etc with the aid of a GPS, TNC and radio. In recent years, traffic has moved onto the internet also a number of RF digipeaters and gateways remain.
This page details how I use APRS to transmit my location when out and about in the car, on the bike or walking.
I generally use it for long journeys as a tracking tool for relatives or other operators – If I’m out ‘n’ about and in a beaconing frame of mind, here’s the link to find me on APRS.fi as M0PZT-7.
I use APRSdroid which is a free application and works very well. It supports a number of connection methods to an APRS Server – you can use a full-duplex TCP link which continuously retrieves APRS server traffic or opt for an HTTP/UDP “send-only” method. The latter offers a significant reduction in mobile data used as well as extends the battery life. Due to the send-only connection, I won’t see any messages you send me.
The app is set to beacon once each minute regardless of my speed – but sometimes SmartBeaconing is enabled which increases the beacon rate if I drive above 50mph but decreases it if I go below 20mph. There are also addition beacons in this mode if I make a significant turn.
For use at home, AGWTracker provides a GoogleMap interface that you can use with an APRS Server (you’ll need a passcode to transmit through it) or an external KISS TNC or soundcard interface (via AGW Packet Engine).
The map below shows a couple of journeys: A car trip up the A12 plus a bike ride into town, the local retail park and back home through the park.