Given the fact that my RC as well as my video downlink are working on 2,4 Ghz, I had a lot of noise as soon as I was moving the controls on the RC transmitter. According to Ramon; The interference is not caused by the servos, but by the TX that makes the servos do what they're supposed to do. The spread spectrum RF signal will start to interfere with the video signal that you receive just inches away from the R/C antenna. Separating the powersupplies for RC and Video downlink and adding a TP-link antenna type 2.4GHz 9dBi Directional Antenna TL-ANT2409A will help a lot to reduce the noise.
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See also; Crap KAP