This project is dead.

The nrf24 used to be a cheap way to add a disappointing radio to your project, but its reign is long over.

Now you can buy a complete, FCC certified, bluetooth system on module - including a powerful arm processor with a floating point unit - from a reputable distributor - for less than $6. I've tried The BGM113 from silabs at mouser, and there are even cheaper Nordic modules. The whole system for less than you could put together a nrf24 + processor.

Plop that down on a PCB and go.