This project aims to implement a receiver for Davis Instruments wireless weather stations by making use of inexpensive rtl-sdr dongles.

• Python >=3.12
• uv (https://github.com/astral-sh/uv)
• rtl-sdr: github.com/steve-m/librtlsdr

The following instructions assume that you have already built and installed the rtl-sdr tools and library above. Please see build instructions provided here: http://sdr.osmocom.org/trac/wiki/rtl-sdr#Buildingthesoftware

To build the project, the following commands will install dependencies and prepare the project for execution:

uv sync --all-extras

To run the tests, navigate to the project directory and use the pytest command:

uv run pytest

Available command-line flags are as follows:

usage: rtldavis [-h] [-v] [--version] [--list-rtlsdr-devices]
                [--rtlsdr-device RTLSDR_DEVICE]
                [--station-id STATION_ID] [--ppm PPM] [--gain GAIN] [--no-hop]
                [--mqtt-broker MQTT_BROKER] [--mqtt-port MQTT_PORT]
                [--mqtt-discovery-prefix MQTT_DISCOVERY_PREFIX]
                [--mqtt-state-prefix MQTT_STATE_PREFIX]
                [--mqtt-client-id MQTT_CLIENT_ID]
                [--mqtt-username MQTT_USERNAME] [--mqtt-password MQTT_PASSWORD]

Davis Instruments weather station receiver using RTL-SDR

options:
  -h, --help            show this help message and exit
  -v, --verbose         Increase logging verbosity
  --version             Show version and exit
  --list-rtlsdr-devices
                        List detected RTL-SDR devices
  --rtlsdr-device RTLSDR_DEVICE
                        Select RTL-SDR device by serial number or index
  --station-id STATION_ID
                        Davis station ID to filter for (0-7)
  --ppm PPM             Frequency correction in PPM
  --gain GAIN           Tuner gain. Can be 'auto' or a value in tenths of a dB
                        (e.g., 49.6).
  --no-hop              Disable frequency hopping for debugging
  --mqtt-broker MQTT_BROKER
                        MQTT broker hostname
  --mqtt-port MQTT_PORT
                        MQTT broker port
  --mqtt-discovery-prefix MQTT_DISCOVERY_PREFIX
                        MQTT discovery topic prefix
  --mqtt-state-prefix MQTT_STATE_PREFIX
                        MQTT topic prefix for sensor state
  --mqtt-client-id MQTT_CLIENT_ID
                        MQTT client ID
  --mqtt-username MQTT_USERNAME
                        MQTT username
  --mqtt-password MQTT_PASSWORD
                        MQTT password

This project can be installed as a systemd service on Raspberry Pi OS Bookworm and Trixie.

1. Run the Installer:

Execute the installer script as root:

sudo ./install.sh

2. Configure the Service:

Edit the configuration file to match your setup:

sudo nano /etc/default/rtldavis

3. Start and Manage the Service:

• Start: sudo systemctl start rtldavis
• Stop: sudo systemctl stop rtldavis
• Restart: sudo systemctl restart rtldavis
• Check Status: sudo systemctl status rtldavis

4. View Logs:

Logs are sent to the systemd journal.

• View all logs: journalctl -u rtldavis
• Tail logs in real-time: journalctl -u rtldavis -f

If you are using an RTL-SDR Blog V4 dongle on an older system (like Raspberry Pi OS Bookworm), you may need to update your librtlsdr library to a newer version. The version provided by the OS may not be compatible with the V4 dongle.

To update your librtlsdr library, run the following script as root:

sudo ./install_librtlsdr.sh

After the script completes, reboot your system for the changes to take effect.

The source of this project is licensed under GPL v3.0. According to http://choosealicense.com/licenses/gpl-3.0/ you may:

• Disclose Source: Source code must be made available when distributing the software. In the case of LGPL and OSL 3.0, the source for the library (and not the entire program) must be made available.
• License and copyright notice: Include a copy of the license and copyright notice with the code.
• State Changes: Indicate significant changes made to the code.

• Commercial Use: This software and derivatives may be used for commercial purposes.
• Distribution: You may distribute this software.
• Modification: This software may be modified.
• Patent Use: This license provides an express grant of patent rights from the contributor to the recipient.
• Private Use: You may use and modify the software without distributing it.

• Hold Liable: Software is provided without warranty and the software author/license owner cannot be held liable for damages.

If you have any general questions or feedback leave a comment below. For bugs, feature suggestions and anything directly relating to the program itself, submit an issue.