Yes I have tried searching Google (Google is THE best search engine), but maybe I need to try again....
Nigel,
I'm not actually sending 'data' I'm really sending commands. This project is based on budget :-D So I am making the radio link as cheaply as I know how.
I'm using license free FRS (Family Radio Service) radios which typically a 2 mile line-of-site range. These radios are NOT made for sending data. They are made for voice communications (They are 400 Mhz FM transievers). Thats why I chose DTMF. (BTW, ham operators have had rather good success using DTMF to transmit actual data
)
I'm using them because I can get them off ebay cheaply, and because radios made specifically for communicating between things such as microcontrollers are expensive (especially when they reach the 2 mile range...)
So all that is going to happen is:
Microcontroller A will send a code (lets say DTMF 1) through Radio A. Radio B will recieve this code and send it to microcontroller B which will "hear" it and act accordingly.
Really simple and I figured DTMF would do the job nicely.
Oh, and this remote controll is for a jet powered boat my older brother and I are building. If you know of any better/cheaper way of doing this please tell me.
Thanks!