It looks like a barrel of some kind that the monitor cable passes through. It's typically about two to three times the diameter of the cable and on the order of half and inch to an inch (one to two centimeters) long.So first, what's a ferrite coil?
Start by reading through this (and the surrounding material). You don't have to do everything that is there.So can someone explain how to check the pins and cables? As in, how do i set my multimeter?