Telephone cables are becoming more and more important because they ensure not only better acoustic communication among the users of a telephone network but also better data transmission. In this way they meet the ever increasing demand of users to link up with the whole world by means of a personal computer sitting in the comfort of their own home (INTERNET).To this application IMC has dedicated a range of its production; alongside the traditional telephone cables (TRR) a newer range has been introduced (TRHR). The latter features a screen of DUPLEX tape (Al/PET) and a drain wire of tin-plated copper, which ensures that the transmitted signal has an optimum protection from external electromagnetic interference. Besides, the cores are made of tin-plated copper and paired to reduce the phenomenon of cross-talk i.e. the notable disturbance of a transmission circuit caused by a signal that runs along a second transmission circuit parallel to the first. The colour code of the cores is standardized by CEI UNEL 00724 (CEI 46-5). All the telephone cables are flame retardant according to CEI 20-22 II. The basic components of a telephone cable are:

• Paired conductors
• Polyester tape
• Screen (in TRHR)
• Earth core
• Sheath.

The conductors are paired and then laid up in a way that the maximum length of the wrapping pitch is less than 120 mm (CEI 46-5). The core is made of tin-plated copper with a diameter of 0,60 mm and is sheathed with PVC. In TRHR there is a screen which consists of a duplex tape and a drain wire which also function as earth conductor. In TRR the earth core is coloured as WHITE-RED. The outer sheath is made of flame retardant grey PVC; another colour can be produced on request.