How to make an antenna cable for a TV: features of an antenna cable: device and principle of operation, how to choose a cable for connecting to an antenna and a TV.

Antenna (coaxial) cable serves as a means of connection, and is also designed to transmit analog, digital and other television signals. Under a television signal refers to the transmission of information in the form of images and sound, using electricity.

Features of the antenna cable: device and principle of operation

An important role in receiving and transmitting a high-quality television signal is played not only by the power of the incoming message, but also by the quality of the wire. High-frequency current is transmitted through the inner conductor (central core). Due to its multi-layer design, the antenna cable provides an uninterrupted signal with minimal interference. The antenna cable consists of the following layers:

1. The central wire (core) is an internal conductor for which copper alloy wires are mainly used.
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2. Insulation layer (inner shell). It is made in the form of a continuous foamed polyethylene (fluoroplastic). Which, in addition to insulation, performs the function of ensuring the coaxial arrangement of the internal as well as the external conductor.
3. A layer of aluminum foil. Which forms a screen around the dielectric.
4. Aluminum braid. Performs a screen function that prevents electromagnetic interference. As a rule, it is believed that the denser the braid, the higher the quality of the wire.
5. External insulating sheath. Designed to protect against external mechanical influences, and also serves to counter ultraviolet radiation. Black-braided wires are designed for external use, as they are more resistant to ultraviolet rays. And wires with white insulation are used for internal installation.

REFERENCE! The use of ordinary copper or aluminum wires as an antenna cable is unacceptable, due to the lack of protection from radio interference.

How to choose a cable to connect to the antenna and TV

A good wire is the key to a high-quality TV signal. For proper cable selection, the following parameters must be considered:

1. The impedance should be 75 ohms. This indicator of resistance guarantees the transmission of high-quality images to the TV.
2. The diameter of the cable must be at least 6 mm. Conductors are smaller than the specified diameter, have a more fragile structure, which leads to rapid wear or damage.
3. The value of the specific attenuation should be at least 60 dB.
4. Appearance must match the cable, i.e. it must be marked.
5. The presence of an unpleasant odor is a clear sign of a poor-quality conductor.
6. The conductor must have sufficient flexibility. At the same time, wrinkles during deformation should not form on it.

All antenna conductors are marked, foreign ones begin with RG, SAT, DG prefixes, and domestic ones begin with RK (radio frequency cable). The following models are most common on the market:

1. RG-6. Thickness is from 6 to 7 mm. The core is made of copper-plated steel or copper. It has a protective sheath made of polyvinyl chloride, a foil screen, an aluminum braid. Insulating sheath made of polyethylene. Typically, RG-6 is used to transmit an analog, cable or digital signal. It is the cheapest conductor, of course the quality is not at a high level.
2. RK-75. The conductor is a copper core. Solid or porous polyethylene insulation. The screen is in the form of a braid of copper (tinned) wires and is covered with a sheath of PVC compound. The class is identical to the RG-6 cable, but thanks to an improved screen it allows the transmission of satellite television signal.
3. SAT-50. More expensive wire, the country of origin is Italy. It is a standard coaxial cable with reinforced shielding. Transmits signals of cable, satellite, digital and analog television.
4. DG-113. According to the characteristics, it is a level higher than previous models, but has a higher price category. An additional shielding braid is embedded in the cable, while the value of the specific attenuation is about 90 dB.

REFERENCE! It is recommended to purchase cables of the DG-113 brand. They have excellent values ​​for signal transmission parameters, and also have higher reliability and strength.

How to make an antenna cable connection

In addition to a good signal and cable, the quality of transmission is affected by the correct connection of it to the TV. Connection is made using an adapter in the form of a plug. The connection of the plug and antenna cable is as follows:

1. At a distance of a couple of centimeters from the end of the wire, an incision is made along the perimeter with the knife to the screen sheath.
2. The insulation shell is removed to the inner conductor.
3. The wire is connected to the plug all the way.
4. The conductor is cut off along the border of the external part of the plug.

In cases when it is necessary to connect several TVs to one antenna cable, use adapter-splitters (“crabs”), but the connected adapter reduces the power of the received stream information. The splitter must have the number of outputs equal to the number of connected TVs. Having a free output also reduces signal quality.

Splitters are installed in places with the strongest signal. To compensate for losses, special devices are used in the form of amplifiers. Amplifiers allow you to increase the quality of the television signal and reduce the amount of interference using an external frequency filter.

REFERENCE! If you connect two TVs to one antenna, the signal quality will decrease by 30%.

Adapters allow you to extend the conductors by connecting them together. DTo eliminate unnecessary signal loss, an elongated cable should consist of wires of the same model and brand. Using adapters, you can also repair damaged areas. Signal quality can be affected by strong bending of the conductor, so pay attention to the trajectory of the laid cable.

What plug is needed and is it possible to do without it

The first connections of the plug to the cable were made by soldering them together. Then came the connectors that made the connection using the clamp. To date, use a plug type F-connector. A modern plug allows you to make the connection yourself, without resorting to the help of a specialist. The connection occurs by screwing the connector all the way to the television wire. At the same time, modern connectors provide high message transmission. But do not forget that the quality of the transmitted signal of not only the image, but also the sound depends on the correct connection.

Most receivers do not require adapters for the F-connector. For digital set-top boxes and TVs, an additional adapter (antenna plug) is usually required.

REFERENCE! Plugs are recommended to be purchased in the same store as the cable.

In emergency situations, when you need to connect the antenna to the TV, you can do without a plug. To do this, remove the insulation shell to the inner conductor. Fold the bare wire in half and connect it to the TV, but the signal quality will be low.