There are different types of digital TV coaxial cables, which can be divided into the following types according to the insulation medium between the inner and outer conductors.
The first generation of TV coaxial cables used polyethylene insulation as the filling medium. Although the manufacturing process of this TV coaxial cable is simple and the impedance is uniform, it has been eliminated due to the large signal attenuation when it is used for high-frequency signal transmission.
The second-generation TV coaxial cable adds a chemical foaming agent to the polyethylene insulation material and uses the characteristics of chemical foaming to decompose and release nitrogen when heated to form uniform bubbles in the polyethylene insulation to become a semi-air insulation medium. As the dielectric constant becomes smaller, the electrical performance is improved, but the foaming degree is low (about 50% or less), and the residual moisture is easily absorbed in the medium. When the working frequency is high, the transmission loss will increase. The mechanical properties and moisture resistance are not ideal, and this kind of cable is rarely used at present.
The third-generation TV coaxial cable is a polyethylene insulating dielectric material through physical processing, making it into a longitudinal hole-shaped semi-air insulating medium. The signal transmission loss in this medium cable is much smaller than the first two cables. But its biggest disadvantage is that due to the presence of longitudinal holes, the longitudinal waterproof performance is poor, and water is easy to accumulate in the holes, which makes the performance worse and affects the signal transmission.
The fourth-generation TV coaxial cable is to inject gas (such as nitrogen) into the polyethylene insulating dielectric material to make the dielectric foam. This kind of physical foamed digital TV cable has stable performance, is not susceptible to moisture, has a long service life, and low transmission loss. It has been widely used in cable television and communication networks.
This kind of TV coaxial cable is made by physical processing of polyethylene insulating dielectric material to make it into a bamboo-shaped semi-air insulation structure. The bamboo cable has the same advantages as the physical foamed coaxial cable. This kind of cable and physical foamed coaxial cable are both research and development results in the mid to late 1980s, representing the highest level of cable production in the world. However, due to the relatively low price of physical foam cables, they are more popular with consumers in the market.
Hongsen is a professional manufacturer and supplier of coaxial cable in China, we can manufacture tv coaxial cable, rf coaxial cable, flexible coaxial cable, mini coaxial cable, rg6 coaxial cable, rg59 coaxial cable, rg11 coaxial cable, rg174 coaxial cable, rg8 coaxial cable, etc. Contact us for more details now.