If you mean physically add more channels to a radio box, you cannot. But with the Spektrum Dx6i and a 6 channel receiver, you don't need to use all the available channels, and it leaves you plenty of function for upgrades later on.

It's a solid system at a decent price. The 10 model memory is great, i used my 6i for scale ships, aircraft (r.i.p.), and soon tanks.