OpenTx
Why OpenTx?
About ten years ago, the RC industry made a step change in technology, not only with secure, frequency hopping signal protocols, but also with adopting software defined operating systems. This mirrored what had happened with military communications twenty years ago. The old analogue radios were configured by physically changing the transmitter or by selecting pre-defined options on the user interface via menus. On this Spectrum DX7, I've had to install a rotary encoder to operate the Benedini sounds.
With a software defined radio, the operating system allows the user to re-configure the radio without changing the system physically. So for the Armortek sounds, you could set up a number of virtual switches and allocate them to any of the inputs (sliders, switches, sticks) on the transmitter. Most of the early adopters were using proprietary software and you were effectively stuck with one supplier, who may or may not be meeting the users' needs. Then along came open source software, where the users get to change stuff and influence software development.
This is where OpenTx comes in. It's an open source operating system for RC and is now probably the most used operating system in RC. To quote the OpenTx developers,
OpenTX is open source firmware for RC radio transmitters. The firmware is highly configurable and brings much more features than found in traditional radios. The daily feedback from the thousands of users ensures the continued stability and quality of the firmware.
And it's freeware.
To call it firmware is slightly misleading, it's more than the software interface with the hardware, it's a complete operating system with a very powerful user interface and, uniquely, desktop configuration software which includes a transmitter emulation. So with OpenTx, you can play around to your heart's content on a PC or Mac and not damage your tank. Once you've got the OS doing what you want, it's a simple job to send (
flash
the new setup to the transmitter. This is the OpenTx Companion, with the simulated transmitter on the right, the channel outputs bottom left and the model setup screen top right.
Some major radio suppliers have recognised the benefits of open source software and adopted it as their chosen operating system. The main player is FrSky (not to be confused with FlySky). The definitive FrSky radio was the Taranis series, the lasted being the Taranis X9D Plus 2019.
So what sort of things could you do with OpenTx on an Armortek Model?
- continue to operate as you would with a Futaba or Spectrum analogue radio!
- use a powerful set of telemetry screens to see what the model is doing (which you could also do to a limited extent with Futaba and Spektrum)
- explore new capabilities such as having a number of setups for different running surfaces, easily selected by a virtual switch.
- explore new running modes, such as simulated gear changes, with sounds to match
- combine functions such as sounds and actions on the Armortek options modules (eg gun flash, recoil, sounds, track movement to simulate platform rock on firing the main armament.
And so on. The point is flexibility - to do what you want the radio to do and not be limited by the physical capabilities of the transmitter.
There is a downside, as ever. OpenTx looks a nightmare to the uninitiated. It's like any software - do I choose the simple, user friendly, cheap job and quickly become disenchanted when it doesn't do what you want. Or do I go for the grown up version which I can't use because I don't understand how it works and it looks daunting? We've all been there one way or another.
The good news about OpenTx is that you can safely ignore a lot of the capabilities in first setting up a basic model. And secondly, there is a huge amount of really, really good instruction out there. In particular, there are at least two YouTube channels with a series of videos taking you through OpenTx in simple stages. I can give recommendations if anyone is interested.
Interestingly, FrSky have moved away from OpenTx, and are now offering FROS (FrSky Operating System!). It's very much based on OpenTx but has a more user friendly menu driven front end. On FrSky's flagship transmitter, the Horus X12, FROS had a very cool reception, as has the radio. The next model down, the Horus X10S, is a runaway success but it's interesting that FrSky make great play of saying they still support OpenTx and most users I've seen, including me, have binned FROS and are using OpenTx. Yes, OpenTx takes a bit of learning but it's really not that difficult to know enough to get started.
I'll end with a story. The US and British Armies both developed complex command and control systems made by one of the largest military suppliers. The systems were highly capable but somewhat impenetrable to use. They got a pretty bad press from the users. Enter a relatively small Danish software company, who developed a system which was so simple to use that there was really no need for a user handbook. I talked to a lot of very senior people about both. Some liked the complex systems because it made them feel grown up (but privately recognised how much effort was required to make them work). One Middle East country almost rejected the Danish system because it was thought to be too simple to use because it had no thick user manual and was therefore thought to lack capability. Nothing could have been further from the truth. A truly powerful system is one that doesn't put off the user and hides its power under the hood. With the learning resources now available on the inter net, OpenTx could be that system.
It's no surprise that the Taranis X9D Plus is the new default radio for Armortek.
