What Is This Cylinder On Your Charger For?
I always use to wonder why the charger has a bump and what purpose does it serve?
It turns out that these bumps are called ferrite bead.
This makes the charger much more effective and helps charge your system more quickly.
Their purpose is to reduce EMI and RFI (radio-frequency interference).
It also acts as a choke or inductor that blocks high frequency noise in electronic circuits.
The bead is made up of ceramic compounds, derived from iron oxide and/or oxides of other transition metals.
It helps to prevent the wire behave on over floating current like aerials.
source: www.techworm.net
