Ok, so I'm stuck in a hotel in Darwin, with a new Futaba 6EX.
I thought I'd take it out for some real world range checking...
I placed the TX on the ground at the position indicated in the picture - it was beside a tree with the back of the TX facing south.
I then jumped in the car and drove to Position 1 - During the drive the receiver lost signal as I went behind trees and buildings.
As soon as I had a line of sight view of the TX, the RX locked solid green - This distance was 1.77km
I then drove to Position 2 - Again it lost signal while driving, but when i parked the car, I had a solid green light on the RX (this was while still in the car) The RX was also inside a plastic pelican case inside a thick carboard box (to simulate a fuselage)
When I got out of the car it remained solid green and the only way I could get an occasional red blink was to place myself between the TX and the RX.
The line of sight distance to position 2 was 3.34 km.
From position 2, looking back towards the location of the TX, even cars driving by were tiny indiscernable specks.. There is NO way you could see your plane at this distance...
The following pic shows the locations..
I am very impressed with the range of this Radio. I will be conducting similar checks on my Spektrum DX6i tomorrow..