auto_rx's web interface provides an easy way of seeing what your radiosonde receiver station is doing at any time, and also provides the ability to load and analyse historical flight paths.
Accessing the Web Interface
auto_rx's web interface is served up on TCP port 5000 by default. If accessing it from the same machine that is running auto_rx, then the suitable address would be: http://localhost:5000
If accessing from another machine on the same network as the auto_rx station (Raspberry Pi or otherwise), you will need to find the IP address of the auto_rx station and use that.
Web Interface - Main Page
This page presents a live view of the state of the web interface. The top of the page shows the current auto_rx version and the station callsign. If a new version is available an alert will be shown adjacent to the version number. Below the station information is information on the current tasking of the RTLSDRs available to auto_rx. This will show either 'Scanning', 'Decoding' (with frequency information), or 'Not Tasked'.
Telemetry Table
The telemetry table shows all the available telemetry information for any radiosondes currently being tracked. Clicking on the radiosonde's serial number will open another browser tab showing the radiosonde on the SondeHub Tracker.
Of note is the reported Signal-to-Noise ratio (SNR) - a minimum SNR of ~8-10 dB is required for reliable decoding, and the reported SNR can be used as a station performance metric or used to compare antenna systems.
Web Interface Settings
Clicking the 'gear' icon at the top right of the page allows the users to adjust some settings related to the web interface, such as:
- What fields are shown on the telemetry table.
- Show/Hide the Telemetry Table
- Show/Hide the Scan Plot
- Switch to a 'Dark Mode', for better viewing in dark environments
- Switch to Imperial Units (feet, miles, ft/min)
Scan Plot
The scan plot (when enabled) shows the output from auto_rx's spectrum scanner stage. The blue trace shows the samples spectrum, over the frequency range defined in the configuration file, while the green line represents the peak detection threshold. Signals above this threshold (which are not in the never_scan list) will be further sampled to determine if they are radiosonde signals.
Web Interface - Historical View
The historical view provides a means to plot past radiosonde flights observed by your station. The page consists of a list of observed radiosondes on the left (newest to oldest), with controls above, and a map to the right:
The Home icon at the top right can be used to return to the main page.
Single / Multiple Flight Path Plots
Radiosonde flights can be selected in the table by clicking on the row, or on the checkbox at the right of the row. Once flights have been selected, their flight paths can be plotted using the 'Plot Paths' button:
Click the 'Reset' button to clear all flight paths off the map. The 'Select All' button can be used to select all radiosonde flights, but be aware that plotting many hundreds of radiosonde flight paths can take a long time, and may make your browser tab unresponsive!
Plotting 'Landing' Sites
The 'Plot Landings' buttons plots the last observed position for every radiosonde observed by your station. This provides a rough idea of the coverage of your station. Note that this plots all landings observer by your station, and isn't affected by what is selected in the table.
As with the flight paths, clicking the 'Reset' button will clear the map.
Skew-T Plots
Skew-T plots are the typical method of displaying radiosonde sounding data. They show the variation in temperature, dew-point and wind through the upper atmosphere, and can be used to provide a quick-look of atmospheric conditions. For a primer on how to interpret Skew-T plots, check out this guide.
Skew-T plots can be generated by selecting a single radiosonde flight from the list (first click 'Deselect All', if necessary), then clicking 'Plot Skew-T'.
As you move your mouse cursor over the plot, the values for the nearest altitude (shown in both pressure, and height above ground level) will be displayed. Note that while the wind speed is provided as kph, the wind barbs are shown in knots.
The per-second telemetry data is decimated by a factor of 25 by default to make the plot more readable. This value can be adjusted using the slider available underneath the plot, and clicking the 'Regenerate' button.
Note that auto_rx does not support temperature/humidity data for all the radiosonde types it can receive - refer to the Radiosonde Support Matrix. An error will be displayed if data is unavailable. Some sonde types (e.g. DFM) only have temperature support.
We make no claims about the accuracy of the data presented in these plots! As the Temperature and Humidity calculations are reverse engineered from the transmitter telemetry, they may not include calibration parameters, and so may not necessarily be suitable for serious meteorological analysis purposes.
Thanks to dfelix for their skewt-js library, without which this would have been much more difficult to implement...
Downloading Log Files
If you wish to save a copy of the log files, you can select radiosonde flights from the list (or 'Select All') and click the 'Download Log' button. A zip file containing the requested log files will be downloaded. Note that it may take some time to generate the zip file, especially if many flights have been selected.
Log files are in comma-separated-values format, with the field names provided in the first line.
Advanced Controls
If suitably configured in the station.cfg file, the web interface allows some limited control over auto_rx's scanning and decode functions. These controls can be accessed from the bottom of the main page's settings pane.
Once the configured password has been entered and submitted, the user is presented with controls enabling the disabling / re-starting of the scanner system, and the stopping/starting of radiosonde decoders.
These controls insert events into auto_rx's main scanning system, and it may take some time for the requested action to be performed.