In answer to Wolfgangs questions. I have flown way more then 75 feet away from my transmitter. In response to Gary, He is correct. I am using the mx-20 receiver for flight telemetry only. and the only thing the mx-12 is used for is for the camera/video /gimbal control. I am using the Radian system for all that control. The mx-12 receiver is not hooked into the CS8 flight control in any way. So my only concern would be if somehow the 2 receivers could interfere with each other by being in proximity to each other.