With the advent of satellite and digital TV broadcasting, the question arises more and more often, which cable for TV is better to choose - because it depends on the signal quality. So, example, switching to satellite or digital broadcasting from analog TV, often the equipment is not tuned to certain channels, the image becomes blurry, blurred, ripples and obstructions sometimes appear on the TV screen, although a completely different quality is expected from modern technologies. The main reason for such defects is the technical inconsistency of the old line in relation to the new characteristics of the signal. Logically, that for high-quality operation of television equipment will have to change the cable.
Where to start
It is not difficult and independent to lay a cable and connect TV equipment at home. You do not need special experience or deep knowledge. But make the right choice of coaxial cable (this type is used for modern TV broadcasting) not so simple. Studying only its external characteristics: thickness, color, trying to determine by eye, what it consists of - to buy a suitable copy is unlikely to succeed. You can understand which cable is better to choose, based on the original data. Before, how to go to the store, it is necessary to understand, what characteristics should have a cable network. To do this, you need to find out:
- what signal format it should support (digital or analog TV);
- type and amount of television equipment, which will be used on it;
- place of laying (apartment or large house);
- location of the signal source - an external antenna or satellite dish on the roof of the house or balcony, shield on the stairwell;
- the total length of the network.
The structure of the television cable
Speaking of internal structure, it is possible to tell with accuracy, that all models have a similar filling.
- Internal conductor - it can be made as a single or stranded wire, copper tube. The signal range and possible bending radius depend on the material.
- Dielectric layer - provides immobility of conductors. Can be made of polyethylene, fluoroplastic, foamed polyvinyl chloride or air layer. The wave resistance and signal attenuation depend on the quality of the material, which is transmitted.
- The outer conductor is a braid. Made of foil, corrugated tubes, aluminum film, metal wire. The degree of protection against external electromagnetic interference depends on the quality of the material.
- Shell, which protects the internal structure of the cable.
As you can see, the principle of cable structure is the same, but materials, from which its structural parts are made, differ from each other. How to choose a good option, which would meet the technical characteristics of modern television?
Rules of choice
Regardless of the manufacturer, any television cable to accept the modern format of television broadcasting must have at least resistance 75 OM. The following criteria should also be considered.
The composition of the outer shell
Usually, use either PE or PVC. In the first case, the shell will be white, and in the other - black. Previously it was considered, that for the outer gasket, example, when the antenna on the roof or balcony of the house, a cable with a black protective sheath should be preferred. But today this figure is not critical, and therefore some types of cables with a white protective sheath, for example SAT 703, can be used both for indoor, and external works. The main thing to consider the thickness of the protective layer. It is logical to assume, that the more he, the better.
However, in this case, the whole structure becomes awkward, in accordance, the bending radius will be somewhat limited, this should be taken into account when planning the location of the gasket (the presence of turns and angles).
Characteristics of the external conductor
It should consist of two shielding layers. You should not buy models with one layer, such cable does not meet modern standards of signal transmission. Materials, from which the shielded layers of the outer conductor are made different. In the first models of television cable as an external screen used ordinary braided wire. The main advantage of this model is low cost, however, expect to receive a quality signal, and satellite TV is definitely not worth it. Modern models have a main screen made of metal foil and additional braid, which is also made of metal alloys - it reduces the level of interference from radio equipment and appliances.
Characteristics of the central vein
Usually, the central core is made of copper or other strong metal alloys. To add strength, alloys can also be clad with copper. There are no confirmed facts, that copper lived much better, than alloys of other metals, transmits a signal. But many experts recommend such models of TV cables.
Thickness
Undoubtedly, a smaller diameter cable is easier to lay, it is easy to disguise under a specially designed box, but the signal quality leaves much to be desired. Section in 3,5 mm is the minimum for home use. Otherwise, only main channels can be accessed, as the effect of such a cable will be limited. To watch TV channels with modern extensions, definitely have to buy additional devices, example, digital set-top box for TV. They will be much more expensive, than a cable with an optimal cross section.
Producer
The modern market provides a large number of manufacturers, but this does not mean at all, that everyone promises quality goods. It is worth paying attention to well-established manufacturers, for example Belden, Cavel, Commscope, Mediaflex. This rule also applies to the choice of antenna.
Cable length
To avoid problems in the laying process, it is recommended to buy a cable with a small margin in length in advance. In the first place, this is due to possible mechanical damage during operation, which will affect the signal quality. Damage to the damaged area may be required. The second reason is the relocation of equipment. Often, new interiors lead to rearrangement of furniture and equipment. The big length of a cable will allow to carry out similar works without its replacement.
Keep this in mind when choosing a cable, that the longer the network, the thicker you need to choose a model. In that case, if the cable is purchased for an antenna, which is on the roof, it is better to buy a wire with a larger cross section. in addition, before, how to buy a certain model, should be clarified, whether there are additional conditions for installation. All this information will be useful to you in that case, if you decide to make an antenna with your own hands.
Choosing a TV cable, worth knowing, that there are no special "digital" models, serving to receive the appropriate speech - it's just a marketing ploy. Modern cable devices are broadband, operating frequency of which from 5 to 3000 MHz. Digital and satellite TV just fall into this range.
To get a quality signal from the satellite, you will need information about it, how to properly install and connect a satellite dish.