The schematic assumes you're powering the Arduino with a 9V source. That 9V is what will be powering the fan.
What mosfet are you using in your build (what is the part number of the mosfet)? If your mosfet is not a logic level mosfet -- that is if it doesn't turn on when 5V is put to its gate -- then it will do nothing but get hot.
Graynomad, thank you very much also for the sketch sample. I am also new to the sketches. Is the following sufficient to upload to the Arduino Uno R3?:
Thank you for helping me sort this out. I am new to all of this. Both of your help was much appreciated and I learned more than what was just in this figure.
Chagrin:
A 7805 is a voltage regulator, not a mosfet. Completely different things -- you've got the wrong part.
Hehe, I made that mistake too when i started, cause the things look exactly then same as some mosfets. Then I started doing a big V in sharpie on the voltage regs i bought cause i know im still probably gonna grab one without thinking sometime.
kd7eir,
I don't have anything similiar. I will just have to get one. Will most likely need them in the future. I just had all the wrong parts to complete that figure. Rob also gave me the needed sketch as one wasn't provided. I guess Massimo expected you to know enough code by that point. I'm not that good yet
Nikarus,
That is a great idea of marking the voltage regulators with a V. Thanks for that.
ALL help and comments were much appreciated. I think I can figure it out from here.