Devo7, and the T9x have their own protocols but can work with the dsm2 receivers with some modding.
One thing to point out in case you go off buying one, it is the Devo 7E that can be made compatible with DSM2 and DSMX with just a firmware change, not the Devo 7. One thing against this though is it is not a full range radio, but can be turned into one with a small solder modification inside... so small it's TINY in fact, not at all easy to do. I don't want to discourage you at all, the 7E is a great transmitter and very capable with a few mods and I LOVE mine, but it's not a "take out of the box and fly a BNF" transmitter at all!! You can't ask much more from such a capable transmitter that costs less than $60 shipped though!!
Mine has the WLToys A7109 module (for V9x9 protocol and Flysky too) in it, as well as the stick upgrade, the added 2x three position switches, a nightly release of the latest Deviation with up to 12 channels, and the range mod (which was not easy... very fiddly). All together with the switches and everything else as I have it the price get to around $90, although in my case I only paid $15 for the switches (I wanted the nice pretty flat long arm switches with nuts that matched the ones already on the transmitter) and $2 for nice red stick ends (the plastic ones that come are not good at all, but use the standard M3 thread), the transmitter was a gift, the soldering I did myself, and the A7109 module was taken from a broken V911 transmitter.