You haven't answered my question "what is it supposed to do?" - all you have done is give me some code to read.
The reason I asked the question is so that you would think about your project in order to give me an answer. I get the impression that you didn't bother.
It looks like the Arduino is intended to switch the transmitter on or off and set it to the right frequency? is that correct?
Is that code EXACTLY as you got it? And is your device wired up EXACTLY according to the instructions?
Where doe the "tone" come from? Your diagram shows nothing connected to the left and right input pins.
...R