Recent Technology has provided a new and more secure frequency for Radio Control worldwide, 2.4Ghz called Spread Spectrum Technology.
This provides what would seem to be interference free transmissions and receiving by means of the 79 spots available. One switching the transmitter on the system picks out 2 unused spots and locks onto these, telling the receiver to ignore all others. Therefore it is theoretically possible to have 39 transmissions at once without clashes!!!
The first available outfit in the UK is the Spektrum from the USA which has been available there for 2 years. This also has a Patented feature called Model Match which locks each model in the memory to its own reciver. Therefore it is impossible to try to fly the wrong model on the wrong memory.
This frequency would appear to be legal in most countries so is ideal if you intend to fly your model abroad, and example would be a competition.
It is essential that you check the CE mark is present on any equipment you buy.