OpenWX Deck is handheld weather-radiosonde receiver firmware for the LilyGO T-Deck Plus. It uses the onboard SX1262 radio to receive radiosonde frames, decodes telemetry on-device, shows recovery and navigation information on the TFT, logs to microSD, and serves a phone-friendly web panel over Wi-Fi.

OpenWX Deck is the handheld member of the OpenWX family (alongside OpenWXSDR, OpenWXTTGO, OpenWX Fleet-Monitor and the OpenWX MQTT frontend.

• Version: v1.0.6 (src/config/version.h)
• Licence: GPL-3.0-or-later
• Architecture notes: ARCHITECTURE.md
• Third-party components: THIRD_PARTY.md

All GPIO assignments live in src/board_pins.h.

Currently decoded

• Vaisala RS41 / RS41-SG
• Graw DFM06 / DFM09 / DFM17
• Meteomodem M10 and M20
• Vaisala RS92

Not planned: LMS6, iMet, MRZ.

All decoders are based on the reliable OpenWXTTGO / rdzTTGO / rs1729 decoders for ESP32 platforms.

Receive and decode

• SX1262 GFSK receive at 4800 bps with the RS41 sync word, long-packet FIFO draining for the full 320-byte frame
• Dewhitening, two-codeword Reed–Solomon correction, per-block CRC-16
• ECEF → WGS-84 position, ground speed, heading and vertical rate
• Stale-fix rejection: a position is only shown when the GPS3 block CRC is valid and at least 4 satellites are in the solved fix

Tuning

• Country-aware launch-site channels, read from sondeqrg.txt on the filesystem
• Two source modes: Preset (steps/scans the selected country only) and Set Freq (manual, 400.0–406.0 MHz in 0.1 MHz steps)
• Scanning with a 2.5 s dwell, automatically suspended while a sonde is locked
• Best-RSSI tracking across the scan
• Country, source mode and manual frequency persist in flash

Recovery

• Range, bearing and elevation from the local GPS to the sonde, on the same page as the own-position fix
• Spectrum page: 401.000-406.000 MHz band scan in 50 kHz steps, with the vertical scale following the measured noise floor so noise and signal are both visible
• Read-only SondeHub landing-prediction lookup by serial

Offline Maps

• On device offline Maps for the sonde position
• With mobile hotspot Tawhiri predictions are supported
• Up to 17 zoom levels supported (use MapTiler for offline map generation of your area)
• T-Deck supporting up to 64GB microSD cards (exFAT formatted required)

Device

• OpenWXDeck support several screen templates and layouts, including a tactical view
• Two menu screens, 16 pages behind a 4×2 Home grid, touch or keyboard driven
• microSD logging of tracks, per-sonde summaries and a last-seen record
• Wi-Fi with credentials editable on-device
• Battery percentage, screen/keyboard brightness, auto-dim, touch enable

Bluetooth BLE support

• Full compatibility with MySondy BT protocol 4.1 supporting these mobile device apps:
  • MySondyGo 3.x, 4.x - Mirko Dalmonte, IZ4PNN
  • TrovaLaSonda 2.0.0.68 - Maurizio Butti
  • Hunter Tracker - Giovanni, IN3ISU

You can use each of these apps with this firmware, simply enable BT BLE on the device.

Gateway Web panel

• OpenWXDeck provides an integrated, fully featured web panel with controls if you want to operate a T-Deck at home or remote

• Providing a dedicated dashboard view, livemap and screen mirroring of the T-Deck live screen

• 

• Configuration settings, decoder options, device settings like display brightness, timeout and much more are available

• An integrated filemanager handles up and download of frequency list, temporary logfiles and lastheard sondes also withour an SDcard

Install PlatformIO, then from the project root:

pio run                 # build firmware
pio run -t upload       # flash the T-Deck Plus
pio run -t uploadfs     # flash the web interface from data/
pio device monitor -b 115200

uploadfs writes the LittleFS image holding the web interface (index.html, style.css, openwx.js, livemap.html, livemap.css, livemap.js) and sondeqrg.txt. It is only needed when those files change — UI edits never require a firmware rebuild. If the filesystem was never flashed, the device serves a compact built-in status page instead, so the panel still works.

Clean rebuild:

pio run -t clean
pio run

There is one environment (T-Deck) using a custom board definition in boards/T-Deck.json (16 MB flash, OPI PSRAM, 240 MHz). TFT_eSPI, TinyGPSPlus and the RS41 FEC code are vendored under lib/; the Semtech sx126x_driver and SensorLib are pulled by PlatformIO.

lib/TFT_eSPI/User_Setup_Select.h is modified to select Setup210_LilyGo_T_Deck.h. Do not replace the vendored TFT_eSPI with a registry version without re-applying that selection.

Everything about the station lives in data/config.yaml on the device filesystem, using the same section names as OpenWXSDR: station, telemetry, decoders, logging, webui, openwx, sondehub, import_api. Changing it needs pio run -t uploadfs and no firmware rebuild.

It holds MQTT and SondeHub credentials, copy data/config.yaml.example to data/config.yaml and fill it in.

For the same reason the web server refuses to serve it: the panel reads the harmless subset from /api/config, and writes back one setting at a time through POST /api/config — an allow-list that covers the station identity, the enabled sonde families and the map defaults, and no credential.

The Configuration dialogue on the LiveMap (System → Configuration) edits the same file; a save rewrites one line and leaves the comments, ordering and indentation alone, so the file stays yours to hand-edit.

Launch-site presets are not compiled in. They live in data/sondeqrg.txt on the device filesystem, so changing them needs pio run -t uploadfs and no firmware rebuild:

# country  frequency(MHz)  site-code  site name
DE   405.700   10238   Bergen
DE   403.330   -       TrUebPl 2
FR   404.000   07110   Brest

The site code is the WMO station number, or - for sites without one — those display as the site name alone. The site name is the rest of the line, so spaces are fine. Group by country and sort by frequency inside each country: stepping (Z/X) and scanning (S) follow file order. Up to 64 channels and 12 countries.

If sondeqrg.txt is missing the device has no presets and stays in manual (Set Freq) mode; /api/health reports what was loaded. Defaults at first boot: country DE, 405.700 MHz, Preset mode.

Pages

Space  Scan         L   Logfile        H      Home
D   Decoder         C   Config         I      Help -> Icons -> About -> close
S   Spectrum        Q   Channel        , .    Previous / next page or Home tile
G   GPS             U   Upload         Enter  Open selected Home tile

Home tile carries an icon, a label and its shortcut key with a status bar down its left edge — green, amber or red where the page has a state, chrome blue where it does not. The Scan tile shows the tuned frequency in place of its shortcut key.

Frequency

Z / X   Previous / next preset, or manual 0.1 MHz step
F       Scan on/off
V       Toggle Preset / Set Freq
Y       Cycle country

Wi-Fi editing (Upload page)

N   Edit SSID       Enter / trackball  Save
W   Edit password   Backspace          Delete
                    Space              Cycle ABC / 123 / SYM

In 123 mode W E R → 1 2 3, S D F → 4 5 6, Z X C → 7 8 9, and Q/P act as 0 (the printed 0/mic key does not report through the keyboard MCU on some units). In SYM mode Q T Y U I O P → # ( ) - ' " @, A G H J K → * / _ ; :, V B N M → ? ! , $.

Web Mode uses Wi-Fi STA only — OpenWXDeck joins an existing network (for example a phone hotspot) and you open its IP address. It does not create an access point and does not scan for networks.

Routes:

GET  /                    dashboard (data/index.html from LittleFS)
GET  /livemap.html        map view
GET  /api/status          cached device status (rebuilt at most once per second),
                          including decoder frame counters and sonde velocities
GET  /api/sondes          currently received sondes, OpenWXSDR shape
GET  /api/health          radio / decoder / GPS / storage / network state
GET  /api/control?cmd=…   queue a control command
POST /api/control?cmd=…

/api/sondes and /api/health follow the OpenWXSDR REST surface so the same consumers can read a handheld and a Pi station.

The panel follows the OpenWXSDR dashboard: indigo/purple gradient, white cards, stat tiles, a receiver panel with a status badge and manual tune, configuration cards with accent bars, and a decoded-radiosonde table. It is self-contained — no CDN — so it works on a hotspot with no internet.

Map View (livemap.html) opens an OpenWXSDR-style map page: Leaflet map on the left, a sidebar with System Statistics (active sondes, session frames, frequency, RSSI), the sonde cards and System Health on the right. A card stays green while the sonde is being received and for two minutes after its last frame; older ones drop into Recently received. Both the flight track and the sonde list are built in the browser from what the device reports, so they start fresh on reload. A map needs tiles, so this one page loads Leaflet from a CDN and falls back to a notice when there is no internet; the sidebar keeps working from the device either way.

It shows sonde type and serial, frame number, RSSI and peak RSSI, sonde and local position, range/bearing/elevation, frequency, country and site, scan and logging state, battery and Wi-Fi status — and can change country, source mode, frequency, scan, SD logging, brightness, touch, auto-dim, counters and Wi-Fi credentials.

Radio capture keeps priority: the web server is handled in short non-blocking calls and the page reads a cached snapshot.

With a card present, logging can be toggled with L, from the Logging page, or from the web panel:

/logs/index.csv              one row per sonde seen
/logs/latest.csv             most recent track
/logs/last_seen.txt          last-seen record
/logs/sondes/<serial>/       per-sonde track and summary

Without a SDcard, OpenWXDeck runs normally with logging disabled.

• Predictions are read-only and require internet access to SondeHub
• MQTT telemetry upload to OpenWX only yet — MQTT upload to OpenWX
• No sondehub upload yet — SondeHub upload are planned, data verification is pending
• No RTC/NTP: logs carry uptime, not UTC y may not report through the keyboard library

1. Verify decoders: RS41, DFM, M10, M20, RS92 upload by Sondehub
2. Telemetry upload to SondeHub
3. Enhanced use of the ESP32-S3: dual-core radio/UI split, interrupt-driven sync detection, PSRAM buffers

Only receive signals you are legally allowed to receive in your location.

Radiosonde recovery may involve access restrictions, private land, roads, weather, water, cliffs, trees, livestock and other hazards. Follow local law and obtain permission where required.

OpenWX Deck builds on the radiosonde decoding work of:

rs1729/RS

DL9RDZ/rdz_ttgo_sonde

DL2MF/OpenWXTTGO

A-DECK SondeDeck

with Reed–Solomon and geodesy from Christian Rabler's dxlAPRS. THIRD_PARTY.md has the details and the licences.

OpenWXDeck is not affiliated with or endorsed by SondeHub.

Released under the GNU General Public License v3.0 or later — see LICENSE and THIRD_PARTY.md.