Certificates of deposit, or CDs, are fixed income investments that generally pay a set rate of interest over a fixed time period.
When referenced to the local common or ground, a common-mode signal appears on both lines of a two-wire cable, in-phase and with equal amplitudes. Technically, a common-mode voltage is one-half the vector sum of the voltages from each conductor of a balanced circuit to local ground or common.
Shield common mode impedance from cable end-to-end has to be very low (this makes the system stable by confining current to the cable tested) Center conductor (inside current) has to be known. The cable must be terminated by impedances similar to the real-world application.