Some txs emit a positive pulse signal and work with rcvrs that use a positive pulse signal - Airtronics is a positve pulse system. Hitec is negative pulse, so is Futaba I think. I have a Hitec Eclipse radio that can be programmed to transmit + or -. The Airtronics RD 6000 can be programmed to put out + or -. I have used Hitec rcvrs with the RD 6000 and Airtronics rcvrs with the Eclipse. It is done all the time. So it can be done but only with compatible sets.