Programmable Radios with More Than 6 Channels
 

Why do people buy programmable radios with more than six channels for airplanes? Say, for example, an eight or nine channel radio. I see a need for throttle, rudder, elevator, ailerons, flaps and retracts, which makes six. Are there additional programmable features available on say, a nine channel radio, that aren't available with a six channel programmable radio?

Thanks,

Travis

Programmable Radios with More Than 6 Channels
 

It all depends on the plane we are discussing. There are some with 4 servos in the wing all connected to individual channels. (Not using a Y cord)
Ducted fans have a potential channel for mixture control.
Some have a dedicated servo for steering the nosewheel, jets have a need for brakes.

I just like to have more knobs and switches than the next guy.......

Programmable Radios with More Than 6 Channels
 

Maybe bomb dropping for a 7th channel and smoke on the 8th channel ......

I don't know..

I was going towards the JR-662 radio and someone mentioned the Hitec eclipse 7 and after I followed up the eclipse could be argued to be a better radio with the bonus of an extra channel and about the same price as the JR-662 and cheaper the 378 -TX

Programmable Radios with More Than 6 Channels
 

When you start running planes with multiple servos per channel (say, two servos each for ailerons and elevators), it is really nice to use a channel for each servo instead of using a y-harness. Most 6-channel radios have mixing for two aileron servos, but then you lose a dedicated proportional flap channel (though you can run flaperons). I have a 6-channel on my Dave Patrick Extra, but I wish I had another channel so I can fine-tune the elevators instead of running a y-harness.

Programmable Radios with More Than 6 Channels
 

Sorry for my ignorance………..

On a 6 or even 8 channel radio you still only have 2 levers that move up/down and side to side so this controls 4 channels………how do you control the other channels?

Programmable Radios with More Than 6 Channels
 

Ryan,

I am not sure I understand. Are you saying, for example, that if you wanted to use two servos for the elevator, you would connect each to its own channel instead of using a Y-connection and running both off the elevator channel? If so, then would you program both channels to be controlled by the elevator stick? What would be the advantage of this over using a Y-connection? They are both connected to the same control surface, right? Please excuse my ignorance. I am a beginner with a 4 channel (non-programmable) radio.

Thanks,

Travis

Programmable Radios with More Than 6 Channels
 

If you want to see actual examples of the how and why, download a copy of the Futaba 8U Super radio manual.

http://www.futaba-rc.com/manuals/index.html

When not using a Y cord, you use what is called mixing.
A lot of the mixes are pre canned in the radio, such as the dual elevator. One reason this is used is for planes with 2 ele servos in the tail. The servos are actually mounted in the opposite sides of the fuse. If you could only use a Y cord, the servos would rotate in opposite directions. Using the mix in the TX allows the servos to operate together off of 2 different channels and rotate the same direction. (as if there was an axle connecting them)

There are also free mixes available in the computer radios. With these, it is pretty much up to your imagination. Over the summer, I put floats on my Kadet. Instead of fooling with mech linkage from the rudder to the water rudder, I added a servo for the water rudder and used a mix to slave it to the rudder channel.

Programmable Radios with More Than 6 Channels
 

individual channels for surfaces also allows some unique maneuvers, such as dropping both ailerons and raising the elevator at the same time, or possibly slaving the elevator halves together with the ailerons. (insane roll rate) There are other examples of things you could only do using multiple channels like this. (btw, those features would be controlled using some of the switches you see, flying with them all the time might be nearly impossible...)

Programmable Radios with More Than 6 Channels
 

Dogz and Bluemax3,
Flatfour pretty much summed it up. It should be noted, however, that there are y-harnesses that have built-in reversers for one side, so that the servos will travel in opposite directions. That's what I have on my DP Extra, and it works well. However, if the servos don't center perfectly with each other, you may end up with more travel on one elevator than the other. This is where multichannel mixing comes in.

For example, in Futaba radios, channel 2 normally controls the elevator servo. But the 8 and 9 channel radios use channel 8 as the second elevator channel, if you decide to activate that function. So basically you have channel 2 controlling the left elevator and channel 8 controlling the right elevator, and both are activated using the elevator stick. The advantage to this is you can fine-tune the centering AND travel for each elevator half. Don't worry though, it's nothing you'll need to concern yourself with until you start flying larger planes with split elevators. I flew a standard 4-channel radio for several years without needing (or wanting) to upgrade.

Programmable Radios with More Than 6 Channels
 

I started out with 4 channels, found myself needing more and moved to a 6 channel radio. That worked well until I got a helicopter. I really needed a radio with a few more flight modes to get the most out it, so that's what I got (XP783). After I while I tossed in some more electronics, and wanted 8 channels. Now I've got an 8103. Hopefully I won't have to move up to a 10X anytime soon. :)

For my Ultrastick, I use seven channels: elevator, rudder, throttle, left aileron, right aileron, left flap, and right flap.

For the helicopter, I use eight: collective, throttle, cyclic (2), tail rotor, gyro, govenor, and I'll be adding a Co-pilot for the eigth.

The additional channels beyond 4 are controlled by switches, mixes, or mixes enabled by switches. There's some knobs to be found there too. :) It sounds complicated, but it really isn't once you start playing around.