What is a symmetrical cable?

Symmetrical cables are manufactured from pairs of twin conductors called cores within a protective jacket. In order to reduce the interference between each pair of wires, each pair of wires is made into a twisted shape, which is called twisted pair. The twisted pair is two copper wires with a diameter of 0.32mm~0.8mm, which are twisted and twisted after insulation and other processes. There are two types of unshielded twisted pair and shielded twisted pair. A cable composed of multiple twisted pairs is a symmetrical cable. The core wire of the symmetrical cable is thinner than the open wire, with a diameter of 0.4mm~1.4mm, so its loss is larger than that of the open wire, but the performance of the symmetrical cable is more stable. Symmetrical cables are widely used in wired telephone networks for subscriber access circuits. The amplitude-frequency characteristic of the symmetrical cable is a low-pass type, and the crosstalk increases with the increase of the frequency, so the degree of reuse is not high.
Symmetrical cable: It is a communication cable composed of two wires with the same wire quality, wire diameter and insulation resistance to ground, but insulated from each other, forming a pair of transmission loops, and twisted by multiple pairs of such wires.
Chinese name: symmetrical cable
Foreign name: Symmetrical Cable
Aliases: none
Applied Discipline: Information and Communication
Features: same resistance to ground, two identical wires, transmission loop, twisted