FYI, it is very easy to display convenient live MAVLink data on your (9X/9XR/etc) radio screen using OpenTx and OpenLRSng. You can also simultaneously pass the data to Mission Planner running on your PC via a USB FTDI cable (3v3).

3691052045?profile=originalI use a 9XR radio running OpenTX compiled with EXT=MAVLINK (or installed automatically using the Companion9X app by ticking MAVLINK extension), and the latest version of OpenLRSng (Gitsly branch). I use a cheap OrangeRX Tx module ($29) in the 9XR, and OrangeRx Rx module ($19) in the plane. This gives me 433MHz RC control over the plane, as well as a MAVLink-compatible serial link (57600 baud, 19200 datarate). No need for extra XBee/3DR/RFD radios.

With this cost-saving combination, I get MAVLink data displayed on my 9XR screen (mode, nav, link, batt, GPS, etc), and by plugging a FTDI cable between my Tx module and laptop, Mission Planner also gets live flight data - normal display of flight data, maps, etc.

The upside is low cost and only the 433MHz RF channel used (no extra modem transmitting other frequencies), which also gives power consumption, weight reduction, and possible range benefits (less RF near antennas as opposed to using a separate telemetry radio).

I just thought it was a setup worth mentioning for new and budget conscious DIY-ers, or those wanting a second, less hard-core setup, such as on a slope soarer.

The original setup discussions (parts out of date now) and procedure summary is here:

Devices are here:
- OrangeRX LRS UHF Tx module 100mW (~$15):

- OrangeRX LRS UHF Tx module 1W (~$30):

- OrangeRX LRS UHF Rx (~$15):
- Turnigy 9XR radio (~$50):

NOTE: for 9X/9XR you will need to make a few small mods to the module connector pins on the 9XR/Tx to enable bi-directional serial I/O.

Special thanks to Kha (OpenLRSng), Martin (Gitsly/OpenLRSng) and Rienk (OpenTX/MAVLink) to get this operational.

Rienk's dev thread:

Companion9X for radio firmware:

Martin's Gitsly/OpenLRSng firmware for Rx/Tx modules:

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –


    • It must be possible to hookup another OpenTX receiver to a laptop over an FTDI cable in order to prevent needing to run a cable from the transmitter. Has anyone tried this? I imagine it should be pretty straightforward. I think this would give you the best of both worlds.

      • Yeah thats a good idea.

        The RX modules are pretty cheap. You would just need to pair the RX with the other RX - i imagine this could be done in the openlrsng google chrome extension?? Anyone know if you can pair multiple RX's?

        I was going to do the above mod to my 9XR then saw the intricate sodlering inside the 9XR - No Way!

        I think i may need the extra RX. Whats the best way to get the serial data out of the orangerx RX in the 9XR into a ftdi usb adapter. I didn't see that mod in the thread - only the 9XR displaying telemetry?


        • Unfortunately, another RX module would not work, since the RX module is synchronized with the TX. Also it's the RX on the plane sending the telemetry data for the TX to receive. So what you would in theory need is another openlrsng module (let's say the OrangeRX thing) running some special code which just monitor telemetry packets sent from the RX on the plane without sending anything itself (could be done in theory) 

          BUT: I suggest plugging in a small serial bluetooth module (like JY-MCO) on the serial port of the TX module. Select this in MissionPlanner, then off you go. 

          That's how I do it. We even got a fix for the 'element not found' bug in mission planner nowadays.



        • Another option people have tried is to attach a bluetooth serial tx inside/on the TX module, then you can connect via bluetooth to your tablet/computer to eliminate the cable.

          • Yeah that would be perfect.

            Do you know where there would be a guide on how to do that? I would need a usb Bluetooth adapter for my tablet as well i think, as i don't think its built in. Would i then just click the normal connect button in droidplanner?


  • Does anyone know someone in the Essex area that maybe able to do this mod for me (for a price :) ).

  • This is great work!

    I've got some parts on order to try this out, but I'm also interested in controlling my quad via an android tablet without an RC tx (possibly via a bluetooth game controller for manual flight as well). Is there some cheap hardware I could use to connect up Droidplanner or Andropilot directly to the Orange LRS rx?

    And as a bonus: The orange LRS hardware seems to be limited to a slower baud rate than the 3dr radios: is this a hardware limitation, or software?

    • IF you only want to connect your tablet to receive the mavlink just use a $6 bluetooth module connected to the LRS...

This reply was deleted.