Radio Remote Control Using DTMF

Hi everyone,
My name is Nhan, from Australia.
I am very interested in the project "Radio Remote Control Using DTMF" and planning to build one as my school project. But I am not very sure and clear of how the two circuits (transmitter and receiver) work in details
Could someone kindly help me out, thanks very much.
Nhan

hi nhan
and i nterested
any one help

Why use old DTMF? The output would be simply on and off.

Why not use the digital proportional pulse-width-modulated signals that are used by model airplanes, boats and helicopters? They control servos that move any amount you need.

Here is schematic of a DTMF remote controller and receiver.You can use decoder and control upto 10 devices.