To use a MPX transmitter, in the USA, with a Futaba PPM receiver (or anything that is the same shift as Futaba), you must first have Ernie Pritchard do a mod. Stock, the TX works with any JR shift PPM receiver. Ernie installs a "shift switch" that allows you to change shift from positive to negative so that you may use any PPM receiver. I have the switch, but since I now have a bunch of IPD MPX receivers, I don't use it much anymore.