OpenScanner

OpenScanner is a high-performance, web-based digital radio scanner designed for the Raspberry Pi (optimized for Pi 5). It combines a robust .NET backend with a modern React frontend to provide real-time P25 digital voice decoding, live spectrum analysis, and AI-powered transcriptions.

Key Features

• Digital Voice Decoding: Stable P25 Phase 1 decoding via rtl_fm and dsd-fme.
• AI Transcriptions: Integrated Whisper AI (whisper.cpp) for automatic speech-to-text logging.
• Fire Tone Out Detection: Detects and alerts on specific 2-tone paging sequences (e.g., Fire/EMS dispatch).
• Real-Time Synchronization: State (locks, holds, status) is synced instantly across all connected browsers.
• Modern Dashboard:
  • Live Waterfall: Visual scrolling spectrogram of decoded audio.
  • Transmission History:
    • Hierarchical Tree View: Organize logs by Year, Month, Day, and Channel for easy browsing of massive datasets.
    • Live Activity: A dedicated "Recent Activity" section for monitoring incoming transmissions in real-time.
    • Integrated Search: Powerful search bar to find transmissions by transcription text, channel names, or frequencies.
    • Instant Playback: One-click listening for all recorded transmissions.
  • Channel Management: Full database control to add, edit, or delete channels. Includes frequency hold and scan resume.
• GPS Integration: Live tracking of location, altitude (Imperial units), and satellite count.
• Swagger Documentation: Full OpenAPI/Swagger UI for API exploration.
• Service-Ready: Automated installer configures OpenScanner as a systemd service on port 80.

Hardware Requirements

• Raspberry Pi: (Pi 5 highly recommended for Whisper AI performance).
• RTL-SDR Dongle: (RTL2832U based, such as RTLSDRv3 or v4).
• GPS Receiver: (Optional, any USB GPS receiver compatible with gpsd).
• Antenna: Tuned for your local 150-800MHz public safety bands.

Quick Start

1. Clone & Install

The unified installer handles everything: it installs required system libraries and radio drivers (DSD-FME, mbelib), builds the .NET backend and React frontend, and sets up Whisper AI.

# Clone the repository
git clone https://github.com/briannippert/OpenScanner.git
cd OpenScanner

# Run the installer (do NOT run with sudo, it will prompt for password when needed)
chmod +x scripts/*.sh
./scripts/install_service.sh

2. Access the UI

Once installed, open your browser to: http://<your-pi-ip>

For API documentation, visit: http://<your-pi-ip>/swagger

Installation Options

• Full Install: ./scripts/install_service.sh (Builds everything and installs the systemd service).
• Dependencies Only: ./scripts/install_service.sh --deps-only (Installs all required system libraries, radio drivers, and Whisper models, then exits without building the app or installing the service).

Running on macOS

OpenScanner also runs on macOS (Apple Silicon and Intel) for development and desktop use. The macOS setup script uses Homebrew to install dependencies, builds whisper.cpp and DSD-FME from source, builds the app, and prints how to run it. macOS has no systemd, so it does not install a background service.

git clone https://github.com/briannippert/OpenScanner.git
cd OpenScanner
chmod +x scripts/*.sh

# Installs deps (Homebrew + .NET 10 + whisper.cpp + dsd-fme) and builds the app
./scripts/install_mac.sh

# Dependencies only:
./scripts/install_mac.sh --deps-only

Then run the app and open http://localhost:8080 (Swagger at /swagger):

cd server/OpenScanner.Server
dotnet run -c Release --urls "http://0.0.0.0:8080"

Requirements: Homebrew and macOS 13+. The script installs the rest (rtl-sdr, ffmpeg, coreutils, the .NET 10 SDK, etc.).

No SDR hardware? OpenScanner ships with a mock radio source so you can run the full UI without a dongle. Set the provider to Mock in server/OpenScanner.Server/appsettings.Development.json:

"Radio": { "Provider": "Mock" }

GPS (optional): OpenScanner connects to gpsd on localhost:2947; install and start it via brew install gpsd if you want live location.

Note on external tools: OpenScanner resolves rtl_sdr, rtl_fm, ffmpeg, and dsd-fme from your PATH and common install locations (Homebrew's /opt/homebrew/bin and /usr/local/bin, plus the standard Linux paths), so the same code runs on both the Raspberry Pi and macOS.

Updating

To update OpenScanner to the latest version, simply navigate to the project directory and re-run the installation script. This will pull the latest changes, rebuild components, and restart the service:

./scripts/install_service.sh

Management

• Status Check: systemctl status openscanner
• View Logs: journalctl -u openscanner -f
• Uninstall Service: ./scripts/uninstall_service.sh
• Data Location: Database and recordings are stored in the /data directory in the project root.

Acknowledgments

• DSD-FME: Digital voice decoding.
• whisper.cpp: High-performance local AI transcription.
• FftSharp: Fast FFT calculations for the live spectrum.
• NSwag: OpenAPI/Swagger integration.