APRS — Getting Started with Automatic Packet Reporting

What APRS Is

APRS (Automatic Packet Reporting System) is a real-time digital network operating on 144.390 MHz in North America. Stations transmit short packets — GPS positions, weather data, text messages — that are received by digipeaters (relay stations) and uploaded to the internet via iGate stations. The result: your position appears in real time at aprs.fi on a live map, visible to anyone worldwide.

What You Can Do with APRS

• Vehicle tracking — Your position updates automatically as you drive. Other hams can see your location on aprs.fi.
• Event tracking — Public service events use APRS to track volunteer positions across a course or event area without radio voice coordination.
• Weather data — Home weather stations transmit temperature, wind speed, rainfall, and barometric pressure to the APRS network.
• Messaging — Short text messages between APRS-equipped stations, delivered store-and-forward over the network.
• Object and item beacons — Mark a fixed location (repeater, emergency coordination point, event stage) on the APRS map for others to see.

Getting Started — Equipment Options

All-in-one APRS radios: The Kenwood TH-D75 (~$550) and Yaesu FT5DR (~$400) have built-in GPS and APRS. Turn them on, configure your call sign, and you are beaconing your position on 144.390 MHz.

Smartphone + Baofeng: Install APRSdroid (Android, free) on your phone. Connect your phone's audio jack to the Baofeng's mic/speaker jacks with a cable. APRSdroid encodes APRS packets as audio tones and your Baofeng transmits them. Your phone's GPS provides position data. This works but requires careful audio level calibration.

Dedicated tracker: A Mobilinkd TNC2 or similar Bluetooth TNC connects wirelessly to APRSdroid and provides more reliable encoding than the direct audio cable approach.

Monitoring Without Transmitting

No equipment is needed to observe APRS. Visit aprs.fi to see the live national APRS map — all stations currently beaconing appear as icons with call signs. Click any icon for details including position history, equipment info, and recent packets. This is a great way to see local APRS activity before investing in equipment.

• Do I need a license to receive APRS?
  No license is required to receive and monitor APRS. Observing aprs.fi requires no radio at all — it is a public website. Receiving APRS packets on a radio requires no license (receiving is always license-free). Transmitting APRS packets on amateur frequencies requires a valid amateur radio license.
• How often should I beacon my position?
  Standard APRS beaconing for a mobile station: every 1–5 minutes while moving, every 10–30 minutes while stationary. Beaconing too frequently congests the shared 144.390 MHz frequency. Most APRS radios and apps support SmartBeaconing — a mode that increases beacon rate during turns and acceleration and decreases it when stopped or moving straight, which is the most courteous and effective approach.