Raspberry Pi APRS Gateway

Build an affordable APRS gateway using a Raspberry Pi and RTL-SDR

The Automatic Packet Reporting System (APRS) is a digital communications protocol for real-time tactical information exchange. This guide walks you through building your own APRS iGate using affordable components.

Project Overview

An APRS iGate receives packets from local RF and forwards them to the APRS-IS network, allowing worldwide tracking and messaging.

Components Required

Raspberry Pi 3B+ or newer
RTL-SDR dongle
VHF antenna (tuned for 144.390 MHz in North America)
Power supply
SD card (16GB minimum)

Estimated Cost

Total project cost: ~$75-100

Software Stack

The gateway uses several open-source components:

Direwolf: Software TNC/modem
aprx: APRS iGate daemon
Raspberry Pi OS Lite: Base operating system

Installation Steps

1. Prepare Raspberry Pi

```bash

Update system

sudo apt update && sudo apt upgrade -y

Install dependencies

sudo apt install -y git build-essential cmake ```

2. Install RTL-SDR Drivers

```bash sudo apt install -y rtl-sdr librtlsdr-dev ```

3. Build Direwolf

```bash git clone https://github.com/wb2osz/direwolf cd direwolf mkdir build && cd build cmake .. make -j4 sudo make install ```

4. Configure APRS

Edit the configuration file to include your callsign and location:

```ini MYCALL YOUR-CALL IGSERVER noam.aprs2.net IGLOGIN YOUR-CALL PASSWORD ```

Performance Optimization

Position antenna for maximum coverage
Use low-loss coax cable
Consider a bandpass filter to reduce interference
Monitor system temperature

Future Enhancements

Planned improvements:

Web-based statistics dashboard
Automatic antenna switching
APRS digipeater functionality
Weather station integration