I'm trying my best to understand and utilise questions that already exist as well as other websites, however I just wanted to check the circuit I've come up with (which is a very simple switch circuit) will work.
I plan on using a BD139 transistor, although I haven't purchased anything yet, so can change to anything really.
The fans are each 0.09A at 12V. I've calculated that R1 should be 360ohms. The 5V control will be coming from an Arduino. I believe it's within the specs of the transistor. Ic max is 1.5A.
Does the circuit look correct? Are there any changes I should make?