Part 1-9 of EN 50289 details the test methods to determine the attenuation of converted common mode signals into differential mode signals due to balance characteristics of cables used in analogue and digital communication systems by using the transmission measurement method. The terms related to this attenuation are defined in 3.1, 3.2 and 3.3. It is to be read in conjunction with Part 1-1 of EN 50289, which contains essential provisions for its application.