I don't see how that is related at all to the OP's question. He has stated that he cannot afford a 2.4 GHz system. Of course, you could send him yours, if that is what is necessary to do his project. I don't think it is.Does your club use 40.685MHz that Google says is used only in Europe for surface models?
We are polite and utilize a frequency management system. We also limit the number of aircraft aloft at the same time (3) to be polite to our neighbors.Does a 72MHz transmitter/receiver detect that a channel is in use then automatically select another channel like happens on 2.4GHz?
They are on the same frequency. You seem to confuse frequency shifting with the ability to select an interference-free channel. My receivers are "scanselect," that is, they can be bound on the ground to the transmitter frequency. The transmitter can be set to any frequency needed.Is a 72MHz model "binded" (bound?) to its transmitter like on 2.4GHz so that no other transmitter can interfere?
Both the 2.4 GHz and 72 MHz (USA) systems work just fine for flying. There is no reason to trash a perfectly good system just so you can be gigahertz and have a shorter antenna.
Your criticism of the OP's radio system added nothing to help him solve his question. I chose not to respond at the time to avoid going OT. However, in my later response, I did mention mention your comment from the perspective that not everyone would agree the frequency of his radio system and its lack of ability to switch channels was a limitation. The number of control channels he has available may be a limitation, but he has stated he can fly the quadracopter with just the 4 channels. I believe it is possible to map those channels to to fly a helicopter and run a surface vehicle using the stick motions he describes.
John