CE3TSK · JTDX Contest Edition

Downloads

Windows, Linux and macOS builds of JTDX Contest Edition, the documents, and the recorded air the measurements were made on. Everything here is free and licensed under the GNU GPL v3.

The program

Windowsx86_64 · v3.0.0-rc11

An installer. Windows 10 and 11, 64-bit.

SHA-256 23d011308a45bc66211d003117fb643d5c21f455bef01d98fc636575788a362f

Linuxx86_64 · v3.0.0-rc11

An AppImage: one file, no installation. Built on Ubuntu 22.04, so it runs on that and anything newer.

SHA-256 33b579d25856ca846e6bc7f0d0c60d7b1df3f7e0191fb2da23b5afd92fe32ead

macOSApple Silicon · v3.0.0-rc11

A disk image. Apple Silicon (M1 and later), macOS 15 Sequoia or newer. Not signed with an Apple Developer ID.

SHA-256 15cba7d5f748dbdc38a0e01f53c3f392802099d94ca806f03f55649a0f5a7d00

macOSIntel · v3.0.0-rc11

A disk image. Intel Macs, macOS 10.15 Catalina or newer. Not signed with an Apple Developer ID.

SHA-256 9b8f8929037f077d892356bc2609418b08a971a73b1d6af2efa64f33dc8d2a68

Before you run it

Linux: make the file executable once, then start it: chmod +x JTDX_contest-*.AppImage and ./JTDX_contest-*.AppImage

Windows: the installer is not code-signed, so SmartScreen may warn about an unknown publisher. The SHA-256 above identifies the file you downloaded; SHA256SUMS holds all four lines.

macOS: the app is not signed with an Apple Developer ID, so the first launch is refused: open it once and close the warning, then go to System Settings > Privacy & Security, scroll to the message about JTDX_contest and click Open Anyway. macOS also allows less shared memory than the program needs - JTDX_contest offers to raise that limit itself and asks for your password once.

Documents

How the decoder works The long explanation, with the diagrams. Reads in a browser, in eight languages. HTML · 615 kB How the SuperFox decoder works How a SuperFox DXpedition is decoded, and what this program adds. Experimental. Reads in a browser, in eight languages. HTML · 374 kB The measurements as a paper Method, tables and conclusions in the form a club or a magazine can print. PDF · 244 kB Inside the FT8 decoder The pipeline drawn out, pass by pass. PDF · 541 kB What changed for WW Digi 2026 The contest support and the decoder work, as taken into that weekend. PDF · 246 kB All the documents in one archive The five above, to read offline. ZIP · 1.2 MB

The air the numbers came from

Benchmark WAV suites and the script Two recorded hours, the crowded-band files with their truth sets, and a script that replays them on your own machine and prints the same columns the documents quote. ↗ The complete source Every change, on GitHub, under the GNU GPL v3. ↗