RE: *Airtronics RD8000 2.4 GHz*
1. By the very nature of 2.4ghz spread spectrum technology, the encoding is proprietary. Much like PCM is for 72mhz. So, even if we used the exact same technology as Futaba or Spektrum, the encoding would have to be different to keep from infringing on their proprietary rights to their own design. Sorry, this technology is not going to be standardized anytime in the foreseeable future.
2. Obviously each company has a chosen a slightly different path for using the technology. There are many interference rejection advantages to Frequency Hopping that makes it very appealing to our engineers.
This is not a very technical explanation but it is detailed enough to make the point...
At many flying fields around the country, there are frequencies that you know cannot be used because there is occasional interference. For example, once or twice a day 12, 22, 36, 48 and 57 get interference. So everyone knows not to fly on those channels...
At the old milesquare field in Fountain Valley, CA we had about 15 of the 50 frequencies that were not safe. That's why the AMA and Radio MFG Assoc worked to get us 50 frequencies!
OK, the same problem is happening in the 2.4ghz band. MANY industries use this band and use it in many different ways. And in some cases have licenses to transmit at much greater strengths than we do.
With Frequency hopping, even if the radio selects a bad "frequency" it's only on it for 1/20th of a second or so and then it moves onto a new frequency. If it hits many in a row, the pilot will feel a little delay. In probably 1/2 a second or so, it's found a frequency not getting "hit" and thus you never really feel any delay at all and your plane NEVER goes out of control. It's constantly bouncing around the band randomly. And thusly, it never gets interference and never causes it (long enough to every feel it...)
I'm not trying to start a debate as to what's better. I'm just saying that FHSS technology is very appealing to many engineers. And, world-wide is showing to be very reliable. Obviously it is not the only way to use the technology, but it is a very reliable way.
The Airtronics system frequency hops. The original prototype has well over 100 flights and is working flawlessly. Stage two of testing which will include pilots from several areas in the country will start at the end of Sept. It will also be tested at different voltages to ensure we do not have any drop out problems.
Whatever technology and encoding we finally use, you should know that it will be thorougly tested both on the bench and in real world applications from Jets to helis to gliders to electrics. Airtronics pilots are eager to test it and are committed to making sure it meets everyone's requirements.
Mike Greenshields
Product Manager
Global/Airtronics