In this article, you will be learning how to set up your OpenTX compatible radio using the OpenTX Companion computer application, and some of its capabilities. I want to be able to address people with different radios, so most of this article will be related to using OpenTX Companion, because it works identically across many radios, while the UI system differs greatly between manufacturers. I will be using Windows 10, but it should all apply similarly to Mac and Linux. Note: a radio, transmitter, and “controller” are all the same thing, just different names.
Disclaimer: This article was written solely by a member of the FPV Community. Views and advice in this article are that of the author and does not necessarily reflect the opinion or views of GetFPV.
What is OpenTX?
OpenTX is a set of open source firmware and software for medium to high end RC radios. While most radios can be used without the OpenTC Companion computer application, it can be used to more easily configure models in radios with smaller screens and allows the use of custom sound and images to be used from an SD card, among other options.
Setting up OpenTX Companion:
Since we will be using OpenTX Companion, you will have to download the installer for your radio from here: https://www.open-tx.org/downloads. After you have it installed, go ahead and open it. You will probably also need to insert an SD card into your radio to hold data for OpenTX. You’ll have to go to the OpenTX website and download the SD card contents for the correct transmitter and OpenTX version you are using as well, it should be at the bottom of each page for a certain version where it says “Download Links.” You’ll want to move those files and folders into the SD card in your radio, and plug your radio into your computer. You might need to do something like hold the yaw and roll trims to the center in order to turn the radio on while plugged in, depending on the model.
After your radio is plugged in and recognized by your computer, you should be able to press the “Read” button on the left sidebar in OpenTX Companion. If this doesn’t work and your pc doesn’t recognize your radio, your cable may not work. Try using a known data-capable USB wire. After you have read the settings from your radio, you should have a window on the left that contains the current settings in your radio, and will display your models. If you just got your radio, you probably won’t have any. At this point, you have set up the OpenTX Companion app and are ready to start configuring your radio.
Creating and Setting Up Models:
My radio already has several models in it, but yours might not. To create a new model or edit a model, double click on its line.
When creating a new model, you can name your model, select multirotor, and jump through the rest of the setup leaving everything default because we will be going through it all in just a moment. After the new model is created and the wizard closes, you can double click on the model to open and edit it. You will see that at the top of the new window that appears, there will be several tabs. I will explain the important parts of each of these tabs in order.
In the first tab, you set generic settings about the model, such as timers, throttle settings, warnings when you first turn on the radio, and the actual radio system itself.
The timers can be named and used to let you know how long you have had an arm switch flipped for or how long your radio has been turned on for. You may have already noticed that if your switches aren’t positioned correctly and your throttle isn’t down, your radio might not be to happy when you turn it on. You can disable that here as well, but be careful because you wouldn’t want to turn on your radio and have the quad arm immediately. You also want to set the failsafe mode to no pulses, and make sure your internal or module radio settings are correct for the receiver you want to bind with.
The next two tabs, Heli and Flight Modes, aren’t needed for your standard miniquad. The fourth tab actually isn’t really needed either, because of the wacky way OpenTX’s I/O system works.
In the fifth tab, mixes, I have created a “mix” for my arm switch. Any switch that you want to output on a channel must be added here, as well as any potentiometers, etc. The setup is fairly self explanatory, just input your settings after double clicking the line.
The next tab, outputs, shouldn’t be needed, but isn’t difficult to use if you do need to use it. The curves tab, logical switches, special functions, and telemetry are all the same way. Some of these tabs might be used later if you decide to do some optional mods for fun, but you have now set up your new model. Now you can bind your receiver to this model and use it.
In addition to the functional features of OpenTX, there are also quite a bit of optional things you can do to spruce up your transmitter. One of the most common things to change is the splash screen or background, depending on your transmitter model.
Under the settings dropdown menu at the top of the OpenTX Companion window, you can select the settings option and open up this menu. Because I have a QX7, I am able to change my splash screen. The settings here may be different for other radios with different screens.
The second common customization option is custom sounds. You can download custom sound packs from online and replace the files in the radio’s SD card. In addition to this, you can actually have the radio play entire songs. This involves using a LUA script and logical switches, and is more in depth than I can explain in this article, but more information can be found on the Project Blue Falcon YouTube channel, which is an excellent resource for OpenTX information, especially involving the QX7.
OpenTX has capabilities well beyond what I explained here, especially with non-miniquad related things, but you should now have OpenTX installed on your radio and be aware of its capabilities. Here are some good resources if you need more help:
- OpenRC Forums: http://openrcforums.com/forum/viewforum.php?f=45
- Joshua Bardwell: https://www.youtube.com/channel/UCX3eufnI7A2I7IkKHZn8KSQ
- OpenTX Discord: https://discord.gg/CZCwVx2
- Project Blue Falcon: https://www.youtube.com/channel/UCObMtTKitupRxbYHLlwHE3w/playlists?view=50&sort=dd&shelf_id=14
- OpenTX Manuals: https://www.open-tx.org/documents