OpenTX vs. OpenTX Companion

What the…???

Perhaps you aren’t as slow as I am, but when I first started experimenting with OpenTX, I was a bit confused. Folks were talking about using something called “Companion 9X” (apparently also known as “Open Companion 9X” and half a dozen other names) to build model profiles, upload/download to and from their transmitters, exchange model setups, and generally do everything but get you a beer. Great! Now not only do I have to get my head around a radically different concept in transmitter programming, but I have to download, install, and learn yet another piece of computer software!

So…What’s the deal?

It seems as if there are two pieces to the OpenTX puzzle. The first is the OpenTX firmware. The second piece is a little computer program called OpenTX Companion.

OpenTX v2.0: This is the computer programming (aka: firmware)that lives in your Taranis and tells the RF section what to do. It is the latest in a series of open source firmware packages that provide the pilot with unparalleled freedom to customize the operation of their radio. Not only does OpenTX let you program your transmitter the way you want to, it also provides direct feedback on the health and performance of your airplane via a two-way (e.g.: duplex) telemetry link. The RSSI function gives you feedback and a warning should you be in danger of flying your airplane out of signal range. OpenTX is, arguably, the most feature laden firmware in existence today. Most of what it can do is available in other packages, but none have the range of features available with OpenTX.

OpenTX Companion: It is perfectly possible to configure and manipulate OpenTX using the buttons and the LCD screen on the transmitter alone just as you do with any other radio. On the other hand, for many it’s much faster and easier to create basic model profiles on a computer using a traditional Windows-like application and then transfer the profile to the Taranis using a simple USB link. These profiles are then tuned/tweaked on the transmitter before your first flight. After flying, you download the EEPROM file from the transmitter and save it as a backup or modify it and upload it back to your Taranis. OpenTX has room for storing 60 models, so chances are you’re not going to run out of slots, however, it’s quite convenient to have different EEPROM’s for different types of aircraft. You can have one for your gliders, one for your electric models, and even one for your heli’s should you be so inclined.

One of the most valuable features of OpenTX Companion is the “Simulator.” It provides an interface for you to learn how to program your TX using the TX buttons, or to check how your servos respond when the sticks are moved. The simulator actually has two parts. One mimics the LCD screen and buttons on the TX, and the other provides real-time feedback when you move the sticks or activate switches so that you can observe the action of (virtual) servos.

Just as OpenTX v2.0 is a descendant of OpenTX r2490 and before, so is OpenTX Companion descended from Companion 9X, which in true open source fashion, has been forked from other graphic interface firmware applications. The advantage of using an application like OpenTX Companion is if you’re a visual learner, you now have the option of creating, modifying, and previewing the expected results of your programming without having to mess with the model.

Is there a learning curve associated with OpenTX Companion? Of course. However, it’s not as steep as you might imagine. There are a few quirks and tricks that you need to learn, but generally OpenTX Companion is very “user friendly.” Two things to keep in mind are: A) Changes made in the transmitter simulator are not saved. In other words, if you set something in the TX simulator it’s not recorded and transferred back to your transmitter, and B) Every new model setup requires tuning when you first fire up your airplane. Things such as servo movement direction may look perfectly fine on the model simulator, but can be reversed on the actual model. Trims, limits, and servo-centers need to be adjusted. Still, the savings in time make learning to use OpenTX Companion well worth the effort, at least in my humble opinion.

Using OpenTX Companion is covered extensively in its own module.

There are some images below showing some of the OpenTX Companion screens.  Check them out.

OpenTX Companion showing an open EEPROM.

OpenTX Companion showing an open EEPROM.

Please Note: The image above reflects two changes in the standard, or normal, OpenTX Companion installation configuration.  First, the icons are the “Classical” theme set (Settings –> Set Icon Theme), and, secondly, the toolbars have been rearranged.  Toolbars can be repositioned by clicking-and-dragging on the row of vertical dots on the left edge of the first icon in the toolbar, just as you can in most Windows based programs.

OpenTX Companion with a model profile open to the Model Setup tab.

OpenTX Companion with a model profile open to the Model Setup tab.

OpenTX Companion showing the Model Simulator.

OpenTX Companion showing the Model Simulator.

OpenTX Companion showing the Model Simulator.

OpenTX Companion showing the Model Simulator.

This is where you’ll spend much of your time checking out all of the things you can configure for your individual model.


OpenTX vs. OpenTX Companion — 4 Comments

    • As I understand it, the total number of memory slots available is a function of the software. The ACTUAL number up to the firmware maximum is determined by the EEPROM. However, I can’t take that to the bank, and will check on it.

      Leonard (mac44mag)

    • The first screen capture above uses the “Classical” theme set of icons (Settings -> Set Icon Themes), and I’ve moved the toolbars to line up at the top of my monitor screen. You can move the toolbars by clicking right next to the small vertical bar of dots next to the first icon in each toolbar and dragging the toolbar to wherever you’d like it to sit.


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