How is cable wire made?

The two types of cable wire used by cable TV providers to transmit programming to customers are coaxial cables and fiber-optic cables. The cable TV industry relies on both types of cable wire to deliver TV shows to viewers in their homes. Traditional broadcast TV, by contrast, uses radio waves that travel over the air to transmit the signal. Coaxial cables work by transmitting radio frequency signals that carry programming to cable TV viewers. Fiber-optic cables use light pulses to transmit the signal. Two distinct processes are used to make the two types of cable wire.

Coaxial cable

A cost-effective method of delivering electronic images, coaxial cable comes in numerous shapes and sizes. The various types of coaxial cable share many important characteristics. Coaxial cable is constructed by surrounding a center conductor with dielectric insulation. A woven copper braid is employed to surround the insulating material. The outer covering, which is also called a jacket, acts as a protective shield to guard the inner portion of the cable from outside electromagnetic interference. It also serves to isolate the center conductor. This process allows the center conductor to do its job efficiently.

The center conductor is the chief component of the cable in terms of transmitting the video signal. The size of the center conductor typically ranges from 14 gauge to 22 gauge. Manufacturers use either copper-clad steel or solid copper to make the center conductor. The conductor has a silver color in its center when copper-clad steel is used in its construction.

Manufacturers use either polyurethane or polyethylene to make the dielectric insulation that covers the center conductor. The use of polyurethane serves to make the cable wire more flexible. Cable workers often find it easier and more convenient to use more flexible cable wire in their jobs. Polyethylene is better than polyurethane at standing up to pressure in the cable wire caused by crimping.

Manufacturers use varying amounts of copper in the outer covering to protect the inner components of the cable wire. The rate of coverage provided by the jacket in typical commercial coaxial cable checks in at 80 percent.

Oliver Heaviside, a British mathematics expert and engineer, secured a patent for the design of coaxial cable in 1880.

Fiber-optic cable

Manufacturers start with glass tubes in the construction of fiber-optic cable. They submerge the tubes in a corrosive pool that contains a solution of hydrogen fluoride. This process removes any oil residue from the tubes. Manufacturers insert the tubes into a lathe. A flame employing hydrogen and oxygen fuses the tubes together at a high temperature. Manufacturers instill a mixture of chemicals into the fused tubes. Silicon is one of the primary chemicals in the blend. The chemical gases heat and leave a white soot on the inside of the glass tubes. This soot becomes the core of the optical fiber. The glass tubes become the protective covering for the fiber.

The soot eventually turns into glass as well when it is heated enough. The tube collapses on itself and forms a solid rod. This process forms the internal structure of the optical fiber.

The next step for manufacturers is to thin out the solid rod. Workers perform this task by attaching the solid rod to an industrial device known as a drawing tower. An oven attached to the drawing tower softens the glass by heating it to a high temperature. Workers stretch the glass until it is formed into a thin fiber. Manufacturers use industrial measuring tools to ensure the fiber is the proper diameter. Manufacturers employ ultraviolet lamps to bake a protective acrylic coating onto the fiber.

Fiber-optic cable is smaller and lighter than most other forms of cable. It is also more expensive to produce.