Can I use a Graupner mc-20 transmitter and reciever

I would like to know if I can use my Graupner MC-20 transmitter and my GR-24L reciever with the Pixhawk system.
If so what do I need to do and how do I do it. What additional pieces of the pixhawk system do I need to make it work. i.e the ppm encoder the PX4FMU and the PX4IO.
Any help would be appreciated.

You can use it as is, just output SUMO (PPM) signal from the rx.
Also, regardin additional stuff, you may consider