Thank you for all these helpful suggestions but I felt that too much time had passed since I first identified the interference problem only 1 hour after receipt. I have returned the RadioLink Tx and two Rx's to the vendor, with the following suggestions, inferred from the above tests, which I hope they will find helpful, rather than irritating:
" (a) The transmitter is low on RF output. This is possible even though the range is as good, or better than, that of the Fly Sky set. If, however, one could, say, double the Tx output, would this not merely make an incremental change to the relative distances at which servos would start to glitch, etc?
(b) Both receivers are faulty. This would be very unlucky, and, because of the range check result, unlikely.
(c) The receiver design is at fault. From what I have read, spurious servo movement and ESC operation, like was often seen in 27MHz systems, should not be possible with 2.4GHz, even when there is interference.
(d) The RadioLink FHSS system is not good enough.
(e) The Fly Sky “Automatic Frequency Hopping Digital System” (AFHDS) somehow “confounds” the RadioLink FHSS, such that it is the only RC brand that cannot be operated nearby. This seems unlikely, in the light of the RadioLink’s response to interference from other sources.
I am disappointed by all this because there are some features of the RadioLink that I prefer over those on the Fly Sky: the joysticks, lanyard-attachment and receiver antenna (easier to install)......"
After sending the stuff back, I thought of another possibility:
(f) The transmitter has a fault, such that it does not correctly identify the free channels on which it should choose to transmit, i.e. like (d), above, but owing to a manufacturing, rather than design, fault.
I will let you know what comes of this, and, for the Westport-Lakers, there might be some familiar scenes videoed from the model, at http://www.youtube.com/user/TimCo158?ob=0&feature=results_main