In November 1781, John Hanson became the first President of the United States in Congress Assembled, under the Articles of Confederation. Many people have argued that John Hanson, and not George Washington, was the first President of the United States, but this is not quite true.
Even and odd mode impedances of a coupled microstrip line. actually I find the reason when you use differential port, the impedance you get is twice the odd mode impedance, whereas if you use common port, the impedance is half the even mode impedance. 1 members found this post helpful.
A simple way of visualizing even and odd signal is to imazine that the ordinate [x(t)] axis is a mirror. For even signals, the part of x(t) for t > 0 and the part of x(t) for t < 0 are mirror images of each other. In case of an odd signal, the same two parts of the signals are negative mirror images of each other.