What's new
Aloft Forums

Welcome to Aloft Forums. Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

The power, flexibility of OpenTX and FrSky

Konrad

Very Strong User
A common concern voiced often from new fliers is how difficult OpenTX is. From an objective perspective I just don't see it!
Actually this complaint comes more from folks moving over from the master/slave menu driven radios rather than genuine first time novice fliers.

That is the key. OpenTX really isn't anymore difficult than the grossly constrained master/slave architecture of say Futaba and JR.

Let me say I hate moving Bit and Bites. That is to say I don't like computers or programing them! My exposure to computer radios goes all the way back to some analog programing like we had with the Ace Silver Seven (now there was a system that had some constraints)! I then had a hand in the digital programing of the JR Galaxy radios (late 80's). This was where I first saw the master/slave programing architecture for mixing. Yikes, this was almost as bad as the old radios without servo reversing! Then in the early 90's I was given an Ace Micropro 8000. This was a lot more logical and had a lot less mechanical constraints. But its real power was in the fine real usable manual that came with the radio. The Ace micropro 8000 was limited as the servo resolution was only 256 bits. As I was flying FAI F3D pylon racer at the time I could see some "steps" low resolution). At that time frame Futaba with Rich Verano was really was supporting pylon racing. So I thought I'd "upgrade" to the Futaba 1024PCM FP-T7UGF Super Seven. What an unpleasant shock it was that with the supplied pamphlet I could barely program a simple 4 ch airplane! This forced me to buy my first after market manual from Don Edberg. With this manual and a week I could program a 6 servo F3B type glider. (This radio programing structure is what Futaba and JR kept until the advent of the 2.4 gHz RF protocols).

I was real proud of what I could get my gliders to do with my Super Seven. Well, until I started to fly gliders competitively. Then I saw what the Airtronic radios with their aftermarket computers and the European Multiplex radios were capable of doing. Seeing what the guys could do with those radios, it was both inspiring and discouraging. I saw Karlton (mr MPX) demonstrate the object based programing architecture that was the Multiplex Profi 4000mc, and knew that was the ticket to unleashing the programing power of the microprocessor based TX!

I bought the Multiplex Profi 4000mc for close to $2k (in 1993 dollars) and just about had a heart attack as nothing moved when I turned on the radio. The radio had so much power that they didn't make any assumption as to what you the owner wanted. One of the first thing you did was define the TX output, the mixers you want to drive that output and then the inputs you wanted the mixer to manipulate. And this was for a channel you just wanted to follow the TX stick! Once you understood that concept you could make a plane do just about anything you could dream up! How liberating this was!

Then some guy in the south bay started to play with the 2.4 gHz chip found in cordless telephones. And by the turn of the millennium my Multiplex Profi4000 was obsolete as the radio RF link was inferior to the new kid on the block, Spektrum! With Spektrum, I was forced to go back the same extremely restrictive programing architecture that I abandoned in the 90's. This was a real hardship.

I was sport flying up in Sonoma and saw a guy actually changing a program without a manual. I was shocked in that the radio looked like an old JR. It was at this time that I learned of OpenTX. And that a local hobby shop was the importer of the radio that ran this "new" object, mixer based program, FrSky. (As luck would have it I had just bought a DX9 6 weeks earlier.) I literally drove down to Aloft and begged Wayne to take my money and bought my first X9D. (Again the radio gods were laughing at me in that 2 months later Aloft had a customer returned X9E). So in less than 3 months I had just bought 3 powerful radios, and had my replacement for my long lost Multiplex Profi400mc

So what all that was to say is that I've had to change radio programing philosophies a few times over the decades. And to show that I have some experience as the end user trying to learn and relearn these programs. I can unequivocally say that OpenTX is a much easier program architecture to work in than any of the other menu driven master/slave concepts. Now if you come from a menue driven master/slave radio you will have to unlearn a lot. But if coming into radio programing you will quickly learn that doing more advanced programing is so much easier with the object based mixer programing architecture.

Now true many of the very basic radio set ups are actually much easier with the menu driven program. With OpenTX one really needs to learn to walk before you run. So may folks moving from the menu driven to mixer driven radios want to be at the level they were with the menu driven program in a very short period of time, like minutes. THIS IS NOT GOING TO HAPPEN!!!! It took years to get as good as you are with Futaba, JR or Spektrum! You will need to give OpenTX a few day maybe a few weeks to unlearn menu programing and just get your head around the mixer based programing!

OpenTX and FrSky are very powerful, even today every time I write a new program (not just copy and make adjustments) I learn ways to make the programing more and more elegant. That is to say that even having used OpenTx since 2016 I've only scratch the surface of all the power available. That is to say I haven't mastered OpenTX but that OpenTX has allowed me to master my models. And the level of programing to do that can easily be extracted from OpenTX!

For example I just set up my 2nd and 3rd Freewing Su-35 using my FrSky X9D. The video is of my first SU-35 using a Spectrum DX9 from 2014?. This is an 8ch ship. I loved how it flew. But I've dragged my feet for 8 or so years to get my other two flying as I dreaded having to program another Su-35. I looked at what I had in my DX9 from the original SU-35 and said no way! So, even though I have a workable program in my Spektrum DX9 I just wrote a whole new program on my X9D.

This new program is for a 13 ch model, using ACCST v2.1.xx, a RX6R to drive the 5 PWM channels . The other 8 channels are extracted from the S-bus line. I also have another RX6R (soon to be a MX+) for RF redundancy. I dread to think how bulky a Spektrum 13ch receiver would be. This SU-35 has a mix of digital, analog, and S-Bus servos. It was easy to use all these keeping the refresh rate and protocols organized. The only gatcha was that I had to solder up an S-Bus harness between the two RXs. What I really like is that most flight surfaces are controlled with curves. This is real easy to visualize in OpenTX.

After writing that SU-35 program. I'm going back to my Freewing 12 ch F-14 program to add/streamline some things I learned from the Su-35. The F-14 is flying just fine. But I now have learned a few things to make the program just that more elegant.

What I'm saying is that while I haven't mastered OpenTX it has allowed me to master the Freewing SU-35 and F-14 EDF jets. You know that after I rewrite the F-14 I'll want to add some new features to both. I'm thinking I need to add a Calibration flight mode to both. This will make it so much easier to balance the left and right control set up and response. Yes, the program can be forever evolving. This is the strength not a weakness/bug in OpenTX!


SU35 PWM and Sbus.jpg
 
Last edited:
Back
Top