Ok, here is what I found:
It has a PWM input for the receiver, here is the source of that info.
Try wiring it with PWM, Pin 1 for ground, pin 3 for power in, and the channels as the schematic shows.
I believe that this may be what you need.
http://www.hobbyking.com/hobbyking/store/__20684__OrangeRx_R710_Spektrum_DSM2_Compatible_7Ch_Receiver_w_Failsafe.html
I don't believe that your receiver is SBUS, I am going to look to see if it is, if not you can get a converter or different receiver. Yours is probably PWM.
4 pounds is not too significant. A Hex with 12 inch props would be able to do the lifting plenty easy and may do the flight time.
Use this tool to test out some ideas.
3 miles is a bit much, but not impossible like MM said, bigger props and Low KV motors. If you can go for higher voltage that is a plus. Approximately what is your budget?
Oh, hahaha. I saw it when I first looked at the post, but forgot about it haha. I see, your question is about the channel for the control.
AIL = CH1
ELE = CH2
Throttle = CH3
RUD = CH4
AUX = CH5
GEAR = CH6
The V2 are a lot better, I have the V1 and they are pretty bad, but fine for the price. The V2 fixed ALL of the problems I (and many other people) had with the goggles and I'd greatly suggest them if possible. The Quantum V2 don't cost much more.
Yeah, I mean people must not understand that these are just methods of transporting equipment that already exist, could a multi-copter have any better chance of using infrared like some sort of x-ray any better than someone on the ground? I bet their just as afraid of anvils being dropped...