FAQ

Where does the data come from?

aprs.ru continuously receives the APRS-IS feed — the internet network to which amateur radio iGates forward packets heard on the air, and to which applications and trackers send their positions directly. The site never transmits on the air and only shows what has passed through APRS-IS.

Why is my station not on the map?

• The packet has to reach an iGate: make sure a working iGate is in range and your path (e.g. WIDE1-1,WIDE2-1) can reach it.
• A malformed packet is stored but gives no position: look up your callsign in raw packets — unparsed lines are shown in red with the reason.
• Packets with NOGATE or RFONLY in the path are deliberately not gated to the internet.
• Identical packets arriving through several iGates within 30 seconds are stored once.

How do I see the movement history?

Enter the callsign in “Track callsign” on the map and choose “Show last” up to 7 days, or pick a day in the date navigator below the tracked station. History for a period can be downloaded with the Data export tool (registration required).

How accurate are the positions?

Accuracy is set by the transmitting station: the standard APRS format gives about 18 metres, the compressed format better, the DAO extension down to tens of centimetres. A station may hide its precision on purpose (position ambiguity) — then the centre of the square is shown. Times are when the server received the packet, not the timestamp inside it.

Can my data be deleted?

Amateur radio transmissions are public, so data is not deleted manually on request. Everything expires automatically: raw packets after 2 days, messages and beacons after 14 days, status reports after 30 days, tracks, weather and telemetry after 2 years. To keep a station off the internet, use NOGATE/RFONLY in the path or do not transmit a position.

What is “transmitting too often”?

If a station sends packets more often than once every 5 seconds, its page shows a warning: such rates overload the shared radio channel. For a car, SmartBeaconing with intervals from 30 seconds to a few minutes is usually enough.

May I scrape the web pages with a program?

Please do not parse the HTML pages: their layout changes without notice, and bulk requests slow the site down for others. Programs should use the API with a key and the KML feed for Google Earth.

Why does a weather station show strange values?

aprs.ru shows what the station transmitted. Sensor faults (e.g. 93 °C at 100 % humidity) appear on the charts as spikes — please tell the station owner.