I'm very new the RC world and I'm trying to pick a radio system for a hexacopter. The three wireless components I'll probably have are the RC controls, XBee telemetry, and a video downlink.
I'm thinking RC at 2.4Ghz, XBee at 900Mhz, and Video at some frequency yet to be determined (maybe 2.4Ghz if I can change the RC system to 72Mhz).
So first, other than preventing interference, is there any reason to have a 2.4Ghz radio system over a different frequency? Any suggestions on what frequencies I should use for the 3 wireless setups thats different then what I wrote?
Also, what is the difference between radio systems? Hobbyking has some that are <$50 like the Turnigy and the HobbyKing models, but others are $200+ !!! Are they more reliable? Why would I want to spend that much more money?
Thanks
Replies
72mhz is older, single frequency, and often prone to interference if flown near other RC clubs (and they're on the same channel as you). 2.4ghz is the newer game, with frequency hopping meaning you'll never have to worry about someone else on the same channel, as you keep hopping every few milliseconds.
Price vs Quality is always a discussion. I personally have a $200 park flyer futaba, and 2 $50 Turnigy9x radios, i use the turnigy to fly all the time (the futaba has a close range only antenna so its only really good for park flyers, or indoor planes). Honestly with a $40 programming board from smartieparts, you can upgrade the firmware on the turnigy9x to get features that $1000 radios offer, however the quality is still a $50 radio, sometimes they go bad, personally one of mine has a bad button, and the other has a bad potentiometer, nothing inhibiting me from flying with it though.
With that you'll want to use a 5.8ghz video link. You could also pay $200 or so for a UHF tx/rx for the turnigy radio (JR Compatible, there are plenty out there if you look into it), that operates at 433mhz so you can use 2.4ghz for video.