Type this into your RasPi Terminal to download the transmission code. This isn't ours, I must credit the original makers of the RasPi radio, Icrobotics.

wget www.icrobotics.co.uk/wiki/images/c/c3/Pifm.tar.gz

Then type 

Is

then

tar -xvf Pifm.tar.gz

Also, put the Python code from Github on the RasPi. You can copy and paste it into your IDE if you want, you will need to be editing it a little bit anyway.

Download a wav file of a solid BEEEEEP sound that lasts at least 2.5 seconds. You should have no problem finding one online for free. The pitch doesn't matter at all. Edit the variables at the top of the code, enter the name of your wav file as well as the frequency you would like to transmit on. Don't include any spaces before or after the words and numbers or it will mess the terminal command up.

Find out the user and Program ID of the Raspberry Pi Radio program.

Type 

sudo ./pifm enterwavhere.wav 89.1

then

 ps -elf | grep python

into the Linux terminal.

You should then see a bunch of results. Find the program, the name should contain the word Pifm.

Write down the programs PID in the Github code afte rits on the RasPi. There should be a variable called "enterPID". Same goes here, please dont include any spaces before or after the PID.

Follow the High Tech Low Tech guide in the links section to set up your ATtiny to be programmed. Upload the ATtiny code from GitHub onto it.