TK24 requires all 4 channels in order to function properly. If you want to use the Tamiya DMD unit, you need to use a Y-cable for the throttle and steering channels. Also, VERY IMPORTANT, both units have a BEC. So when utilizing both boards you need to remove the positive wires from one unit.

So let's say, you remove the positive wires from the DMD RUDD. (Steering) and THROT. (Throttle) servo cables. This way you prevent something from going poof.


(Image taken from the Open Panzer wiki)