OpenTX 2.1.9 Download: Essential Guide for Legacy Radio Firmware
OpenTX 2.1.9 is a significant milestone in the history of open-source radio firmware. While newer versions like 2.3 or the fork EdgeTX have become modern standards, version 2.1.9 remains the final stable release for several legacy AVR-based radios and is known for introducing a revolutionary telemetry system. Official OpenTX 2.1.9 Download Links
To get OpenTX 2.1.9, you must first download the OpenTX Companion 2.1.9 software for your computer. The Companion is used to configure your radio profile, download the specific firmware for your hardware, and flash it to the device. Windows Installer Mac OS X Installer Linux DEB (32-bit & 64-bit) Linux RPM (32-bit)
Note: Windows XP users may need to install the Microsoft Visual C++ 2008 Redistributable to run the simulator. Why OpenTX 2.1.9 Matters
For many users, 2.1.9 isn't just an "old" version; it is the last version to support AVR-based radios. If you are using any of the following hardware, this is likely the most advanced firmware your radio can officially run: Turnigy 9X Go to product viewer dialog for this item. (with stock board) FlySky TH9X Go to product viewer dialog for this item. Go to product viewer dialog for this item. (standard board) Go to product viewer dialog for this item. and DIY MEGA2560 Go to product viewer dialog for this item. Key Features and Changes
The 2.1 branch introduced a complete overhaul of how your radio handles data: opentx 2.1.9 download
New Telemetry System: Version 2.1 replaced fixed telemetry with a "Discovery" system. You must now use the "Discover new sensors" menu item on your telemetry page to see active data.
Enhanced Compatibility: Improved support for various protocols, including better DSM handling and rotary encoder fixes.
Sound Pack Requirements: Because the telemetry system changed, 2.1.9 requires a different sound pack than the older 2.0.x versions. Installation Steps
Install Companion: Download and run the OpenTX Companion 2.1.9 for your OS. Configure Radio Profile
: Open Companion, go to Settings, and select your specific radio model (e.g., Taranis X9D+ Go to product viewer dialog for this item. Turnigy 9X Go to product viewer dialog for this item. OpenTX 2
Backup Existing Data: Always use the "Backup Radio to File" feature before flashing to ensure you can revert if necessary.
Download Firmware: Click the Download icon in Companion. This sends a request to the OpenTX build servers to generate a custom .bin file for your radio's options.
Flash Radio: Connect your radio via USB (typically in bootloader mode or power-off mode depending on the hardware) and select "Write Firmware to Radio". OpenTX 2.1.9
OpenTX 2.1.9, released in late 2016, remains a pivotal version of the open-source RC transmitter firmware because it is the final stable release to support older AVR-based radios. While newer branches like 2.2 and 2.3 have since taken over for modern hardware, 2.1.9 is still the "gold standard" for legacy equipment like the Turnigy 9X and FlySky TH9X. Why OpenTX 2.1.9 Still Matters
For hobbyists using older hardware, this version is more than just a legacy download; it’s a necessity. You own an original Taranis X9D (non-Plus) or X9E
Legacy Support: It is the last version compatible with AVR-based radios (9X/9XR with stock boards, Gruvin9x, and DIY MEGA2560).
Telemetry Overhaul: The 2.1 branch introduced a completely new telemetry handling system compared to the older 2.0 branch, offering a more unified interface for registering sensors.
Stability: As the final release of its branch, it contains all the cumulative bug fixes and refinements developed over the life of OpenTX 2.1. OpenTX 2.1.9
As of now, OpenTX 2.1.9 is a legacy version (released around 2016). The OpenTX project has since moved to EdgeTX (the modern successor) or much newer OpenTX 2.3.x.
However, if you specifically need OpenTX 2.1.9 for an older radio (e.g., Taranis X9D, X9D+, X9E) or to maintain compatibility with old setups, direct downloads are no longer available on the official OpenTX website (they only host the latest 2.3.x).
Here is the best way to obtain OpenTX 2.1.9 safely:
