Unleash Your DJI Air Unit. No Flight Controller Required.

It seems DJI’s definition of ‘maximum power’ was a bit optimistic. Toggling it in the menu was fine, but to actually get what you paid for, your O3 or O4 Air Unit needed an arming command—usually from a flight controller. A bit inconvenient for those of us flying things without one. Luckily, the clever people at ExpressLRS have cooked up a rather elegant workaround.

The solution is beautifully simple. With a new firmware update, your ELRS receiver can now speak the language your DJI Air Unit understands, sending the arming command directly over UART. All it takes is a bit of wiring, flashing the latest ELRS build, and changing one setting to 'DisplayPort'. Suddenly, that flight controller looks a bit redundant, doesn't it?

You can arm it properly with a switch on your radio, or for the truly lazy—our kind of people—enable a 'permanent arm' option in the WebUI so it’s ready to go on power-up. Naturally, there's a small quirk with auto-recording if you do that, but Mads Tech has it all figured out. You can see the whole thing in action below.

This is the fix for a problem that shouldn't have existed, giving you full RF power on your fixed-wing and ground builds without the extra hardware. It’s cheap, it’s clever, and it just works. For the complete step-by-step guide with all the technical bits, read the full post here.