Ever Wonder What Those Thick Bits on USB Cords Are For?
We all have a bunch of random USB and cable cords lying around the house somewhere. Chances are, you have no idea what device each cord belongs to, but here is something you’ll be amazed to learn.
Those little cylinder shaped lumps on the cords are called ferrite cores or chokes. They are essentially just chunks of magnetic iron oxide that are meant to suppress high-frequency electromagnetic interference. So if you’ve ever experienced interference when your cell phone gets too close to a speaker, ferrite cores are there to prevent that from happening to your other electronics.