If you are an RC hobbyist, you know that the software running your transmitter is just as important as the hardware itself. For years, OpenTX has been the undisputed king of radio firmware, offering unparalleled flexibility.
While newer versions like 2.2 and 2.3 have since been released, version 2.1.9 holds a special place in the history of RC. It is widely considered the final, most stable iteration of the 2.1 series—a true "Gold Standard" for many pilots still flying classic setups.
Whether you are looking to update a backup radio or you are curious about this legendary firmware, here is everything you need to know about the OpenTX 2.1.9 download. opentx 2.1.9 download
OpenTX 2.1.9 pairs perfectly with Companion 2.1.9—the desktop simulator and settings editor. Some users prefer this older interface because it is less resource-intensive on older Windows 7 or macOS machines.
Once you have OpenTX Companion 2.1 installed and your radio connected via USB: If you are an RC hobbyist, you know
| Feature | OpenTX 2.1.9 | OpenTX 2.3.15 (Modern) | | :--- | :--- | :--- | | Taranis X9D (original) | ✅ Full support | ❌ Dropped support | | Lua API | Legacy (v1) | Modern (v2 & v3) | | Telemetry screens | Classic grid layout | Customizable widget system | | Multi-Protocol Module (iRangeX, 4-in-1) | Limited, no auto-detect | Full support with auto-detect | | FrSky ACCESS protocol | ❌ No | ✅ Yes | | Touch-screen support | ❌ No | ✅ Yes (RadioMaster, etc.) |
The safest source for an authentic OpenTX 2.1.9 download is the OpenTX GitHub repository. The safest source for an authentic OpenTX 2
Direct firmware file naming example:
OpenTX is managed by a desktop app called Companion. Version 2.1.9 requires Companion 2.1.9. You cannot use the modern Companion 2.3.15 to flash a radio to 2.1.9—the file structures changed significantly.
OpenTX 2.1.9 was released back in early 2016. You probably need it for one of three reasons: