This month, let’s take a look at these four things: crosstalk, differential impedance, EMI, and television transmission. Now, my question to you is, what is the relationship between them? Choose from one of the following: (a) They all depend on the same fundamental phenomenon. (b) They are totally independent phenomenon. (c) Two of them are exactly the opposite of the other two. We don’t often think of these four things at the same time. But before we consider the question, perhaps we should review our understanding about what “electromagnetic” radiation is. The two parts of the word give us a clue.