Nope, but I have used cheap walkie talkies for data transfer. Just output DTMF tones and decode them.Old school! Got part #'s and schematic? Know the baud rate?
from my memory:
Used the Mitel 8870 DTMF encoder, bought it from BA Micro or something similar to that, maybe BA Electro?
Schematic was found in the datasheet, baud rate not sure. I guess it would be limited by the minimum tone length - I think I used the a tone length of 50mS , but I'm sure you can do shorter than that. The datasheet should have info about that. Also, only 16 tones available so you communicate sort of in "hex"