Ok.. They ask for a 7channel rx and they mean to use a 7channel tx with it.
Confused yet? Lol
Ok, the controls and settings of a 600 are no different that your 450 or 250... It's all the same number of servos on your cyclic and tail controls. The throttle servo in nitros is replaced by your esc in the electrics so there is one channel. 3 for cyclic, and two for rudder. 6 channels.
The seventh channel which they say is good to have is for the governor.. For electrics until and unles you are exceeding the gear ratio given to you by the manufacturer or putting higher cell batteries in it, you dont need that. What governor does os limits your head speed so that it keeps in limits of the design and doesn't disintegrate under load. So for that you would use a 7th channel.
It's almost a must with nitros to have a governor. Now I was under the same impression that you can't use a governor on a bird until you have the 7th channel. Until I found that many good governors out there work with 6channel transmitters too. Like I use multigov pro or multigov.. They are great! You had only one head speed of you dont have the 7th channel, thats the one you would program into your governor. This is true for electrics and nitros. Now when you go to 7chanels you get an option to select your head speed out of the two or three options whatever your radio provided you. So say on normal mode you have 1800 rpm, idle up 1 is 1900 and idle up 2 @2100..
So is 7 channel needed for 600 absolutely not. Is it good to have .. yes. But again not required. ESP not for electric. Tiny used to fly (or maiden lol) his 600 electric on his dx6i..
Having a 7 channel rx, you'll NEED a 7 channel tx.
Now as far as flybarless is concerned, all this does not matter. Flybarless doesn't add any channels. It's just a gyro which translates your inputs to the swash and corrects any movements that you didn't intend to happen.
Hope this explained a bit.
That's also one of the reasons I cannot rationalize upgrading my tx. Lol i don't need another channel. And if I upgrade , that'll mean to get the eBay out of it, I'll need to upgrade my rx's on my 600 birds...

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