The mediums over which electrical signals travel can either help or hurt the electromagnetic compatibility of a system. Common mediums include printed circuit board (PCB) traces, interconnects, and cables. In order to see how intrapair skew induces EMI, EMI must first be defined.

A paddle card can be mated with a mating connector, and PCB or FPC can be designed for the plug circuit. Paddle cards are easy to add to ground structures, improving ground return. Impedance matching is simplified, and signal integrity is improved at higher frequencies.