Advances in Computer-Controlled Measurements of Cable Parameters

Since 1967, computer-controlled test systems have been used with great success for the rapid and automatic test and evaluation of parameters of multiconductor telephone cables ranging in lengths from 200 to 20 000 ft. These parameters are important in the design and manufacture of cables by determining transmission efficiency, crosstalk, and noise. These systems have evolved into a second-generation version with improvements in measurement techniques and operational utility. In addition to measurements of mutual capacitance, capacitance unbalance to ground, and pair-to-pair, measurements of capacitance unbalance to shield and resistance parameters such as mutual conductance, conductor resistance, and resistance unbalance can now be made with the same system. This paper describes the structure of these automatic systems and some of the current and future capabilities.