Digital antenna for DVB-T2 own hands

Digital coding of the television signal allows it to be delivered to the receiver, minimizing any losses. The TV needs an antenna for DVB-T2 to support the technology. With their own hands to make such a device is much cheaper than buying a ready-made, paying for it about 3 thousand rubles. Digital terrestrial television replaces all similar types of signal transmission, while offering high-quality broadcasting and a variety of channels.

Changes in the air

To make an antenna for a tube TV of the old model was considered prestigious at the time and showed the level of skill, in the modern world, interest in self-made instruments does not die out, and many make terrestrial antennas DVB-T2 by their own hands. Manufacturers of industrial equipment adapt to the changed reception conditions in that they connect modern electronics to standard known designs, completely ignoring the fact that the main condition of the antenna is its interaction with the air signal.

In recent years, almost all broadcasting has occurred in the DVB-T2 range, which reduces the cost and simplifies, from the economic point of view, the antenna-feeder business of transmission stations. For periodic maintenance requires less highly skilled personnel, his work becomes less harmful and dangerous.

Transmitters of television broadcasting cover the signals of all major cities and sparsely populated villages, so it is very important to catch waves from unserved low-power stations in remote areas if an antenna is installed to receive DVB-T2, which is made of improvised materials.

Due to the expanded construction of reinforced concrete structures in the city, conditions for the propagation of signals in settlements have changed significantly. Multi-storey houses with a metal frame are original mirrors, several times reflecting waves up to full attenuation.

A lot of TV channels are broadcast in the modern air. The digital signal differs from the others in that it is or is or is not, the middle position is not given. Other transmission systems are different in that the channels perceive interference in various ways, which reduces their broadcast quality, sometimes the image may simply disappear. An antenna for DVB-T2, made by hand, will allow receiving the same signal for all channels that show the same quality picture.

The signal of digital broadcasting is special in that it does not interfere with it, if it exceeds the noise by one and a half decibels, then a good reception is carried out. The disappearance of the signal is affected by inconsistency with the cable or phase distortion in any part of the transmission from the camera to the tuner, and the image may crumble into small parts even with a strong signal.

Basic features for antenna manufacturing

Before making the DVB-T2 antenna with your own hands, you should study the principle of its operation.

To capture a digital signal requires a decimeter antenna, which is very simply constructed, even from a simple cable, by making the correct calculation.

The theory states that digital signals are easily transmitted in the decimeter range and can be received by any type of antenna, but this is not always the case.

You can create a television antenna yourself with minimal costs and without the help of outsiders, but you should remember that the received device is inferior to professional devices in terms of reception quality.

Requirements for antennas

New conditions for broadcasting, distribution and reception on the air have changed the basic requirements that TV antennas themselves must match. DVB-T2 canceled previously significant directional and protective effects. They are not important in modern devices, since the ether is contaminated, and it is possible to fight even with small penetrating interference only by means of electronics. At the same time, the self-amplification factor of the antenna (CU) plays an important role.

An antenna that traces aether well has a power margin for the received signal, which allows the electronics to sift it from interference and noise. The modern antenna for DVB-T2, made by hand, retains electrical performance in a natural way, rather than adapting to acceptable parameters using engineering techniques. It is coordinated over the entire operating frequency range without the use of balancing devices.

Characteristics of antenna amplitude and frequency

Antenna is made as smooth as possible, phase distortions arise due to sharp outbursts and dips. Single-frequency antennas are stretched at an acceptable noise-to-signal ratio, so they are put on reception for up to 40 channels. But they are additionally fitted with matching amplifiers that absorb waves or distort phase parameters.

The most efficient DVB-T2 digital antenna with its own hands is manufactured:

• Frequency-dependent - with low indicators, but cheap and easy to manufacture, designed in a short period of time, designed to receive in a relatively pure ether at a small distance from the transmitted station;
• Periodic range, catching all the waves in the space, ideally sorting them, which is distinguished by a simple design, ideally works in tandem with the fritter on the entire length of the reception.

If we talk about the design, the simplest DVB-T2 antenna with its own hands is made in the variant "eight", "Polish" and "square".

An antenna of the type "eight"

Refers to easily designed devices, made as a standard eight, with which the reflector is removed. The ideal material is copper wire, but uses an aluminum strip, corner, tube, tire, other profile. The upper dimension is 140 mm, the lateral part is 130 mm in length, but these dimensions are given for reference; in manufacturing, they should not be kept accurate to a millimeter.

First, a wire 112 cm long is cut off, the first part of 140 mm long begins to bend, of which 130 mm goes to the antenna, and 10 mm remains for the loop. The two following segments are bent equally to a length of 140 mm, the next two to 130 mm, the next pair of 140 mm, then another 140 mm, then 130 mm and make a second loop. The connections are pre-cleaned, connected and soldered, they are also contacts for fixing the cable core.

The cable and plug are stripped using a scalpel and a nail file. After soldering the joints are sealed and glued with a hot gun. If we talk about the plug, the glue is poured into the adhesive joint, then into the cavity of the cap, the excess is then retracted. The joint is assembled so quickly that the adhesive mass does not harden. It turns out an eternal strong and elastic connection. For contact, the ends of the cable are cleaned from the side of the plug by 1 cm, on the antenna side - by 2 cm.

The DVB-T2 digital indoor antenna is also sealed with adhesive by soldered connection, where it is recommended to install a rigid frame at the contact point to the size of the joint. If the device is made for itself and will be rigidly fixed during operation, and the transfer is not needed, then the frame is not made. A device made of this type easily captures digital signals on the direct line of sight of a television tower at a distance of up to 10 km with an outdoor installation.

Using a "Polish" antenna

The "Polish" antenna received its name during the times of the former Soviet Union as a reliable device for receiving signals from Soviet television, as well as channels in the decimeter range. Reception of digital broadcasting on it practically is not carried out because of small efficiency. Some amateurs try to bring the design to the ideal by shortening the long decimetric whiskers and removing the reflector. This change in some cases allows you to adjust the image in a digital format, but you can not talk about a guaranteed receipt of a reliable result. Speaking of Polish devices, we can note the quality work of the amplifier, which effectively works with a digital signal.

Antenna type "square"

Such a DVB-T2 indoor antenna, manufactured by itself, is a modified copy of the standard design known as "three squares", in which there are six components and a matching transformer is provided. A homemade antenna of this type confidently copes with the reception of digital channels at distances of up to 10 km in a straight line, longer distances require a signal amplifier.

The antenna design is simple in performance. The main structural element consists of an aluminum wire of circular cross-section and single-core wires. The wire is bent to produce six squares and make a matching tap, which is a high-frequency transformer, to combine a signal cable and a DVB-T2 antenna with an amplifier. With their own hands perform the soldering of the wire to the points, wind them with a wire of copper and a soldering iron puddle.

Cable to the antenna is attached with special clamps or with the help of ordinary insulation tape. The connection of the cable is carried out with the support placed, a wooden strip or other material is used. When installed indoors or outdoors, the main condition is the exact adjustment to the television tower. This is done with the help of the navigator, if there is no direct visibility, the direction is refined to the effect of obtaining a powerful signal.

Antenna device from beer cans

The technology of manufacturing such an effective antenna is very simple and does not require special skills.

Using a thick awl or screwdriver make a neat hole in the neck of each of the two cans, then screw in them screws. The cable ends are released from the braid, the copper wires are stripped with a knife from the varnish, and they are attached to the screws of the screws. It is very good to solder the resulting compound, but not necessarily.

The digital DVB-T2 antenna is almost made by hand, it remains on the prepared rack or pipe to fix the banks so that there is a distance of 7.5 cm between them. The second cable end is equipped with a standard plug that connects to the receiver, the device is installed in the place of the best signal fixation. Placing this type of device on the street requires reliable protection from the weather. This is done by any waterproof material, often in the course are plastic bottles of large size. The antenna receives up to 15 channels of satellite television and digital broadcasting.

Use of instruments and amplification

At a certain distance from the television tower, the antenna is capable of receiving signals without the installation of additional amplifying devices. To receive the signal from a longer distance, they are stored with a power amplifier with separate power supply. The device is arranged near the tuner, and the matching device is made additionally, for its manufacture, it is necessary:

• Potentiometer for gain control;
• Standard decoupling chokes L4 and L3;
• The coils L2 and L1 are reeled in size from the directory;
• A metal screen for separating the circuits at the output from the device circuit.

Amplifiers put not more than 3 meters from the place where the DVB-T2 antenna is installed from the cable, receiving its own antenna from its antenna cable . When installing the antenna near the broadcasting tower, it is not recommended to use the amplifier in addition, since a powerful signal degrades the image and exerts additional electronic load on the entire structure. The recommended length of the cable is three meters, a larger wire will result in an unbalanced symmetrizer.

The use of a symmetrizer

This device is needed for any type of antenna, it does not matter, it was manufactured in the factory or in the workshop of the craftsman. An antenna for DVB-T2, made by hand, produces good image quality if it is connected to a tuner. If the length of the cable is more than 10 m, when mounting outside the building, there are inconsistencies in the resistance of the external space and the cable. In this case, it is required to use a symmetrizer in the complex antenna solution, which greatly improves the quality of the image on the screen.

Cabling and antenna installation

The main rule is to install the antenna at a height. If this can not be done in the room, you need to take the device to the outer wall. To install the antenna in a private structure, digital broadcast operators count on the device's height of 10 m. If the antenna is located on the first floor of the house, then the nearby metal structures, industry objects cause a deterioration in reception.

When the antenna is placed under a canopy or roof of the house, attention is paid to the roofing material - it should not contain a metallized coating or spraying in the composition. Metal, profiled, iron or foil insulation creates significant interference to the reception of digital television signals.

For high-positioned receiving antennas on a metal mast or a pin, a steel rod of at least one meter in size is connected to which a ground wire is connected. The device located on the roof is included in the common grounding system of the house.

The cable does not lead through the smoke and ventilation ducts, do not hang on existing electrical wires, even if they look more than reliable. Holes in the walls are arranged with a slope, so that moisture from the street does not flow into the interior, use special plugs available for sale. If the antenna is made soundly and correctly, take the cable and wall sockets of high quality, since after the final wall finishing it is difficult to remake the cable in the wall and replace it with a more reliable one.

Observance of safety precautions when installing the antenna

Before installing or adjusting an already mounted antenna at a height, make sure that this action is safe:

• Do not climb on weakly fixed and shaky structures, if high-altitude work is associated with danger, it is necessary to put on the mounting belt and attach it to the fixed part of the building structure;
• It is not permitted to keep the end of the mounting belt to the assistant without fixing it in advance, if the attendant falls, the weight of the body will not be held in his hands;
• It is forbidden to climb to the heights alone, with icing of structures, walk on the old roof, step on the joints;
• Do not install the antenna in rain or fog.

In conclusion, it should be said that it is quite simple to make a self-receiving device in order to watch digital TV. DVB-T2 is an antenna made with its own hands, - in terms of quality (if you follow the right technology) is almost inferior to store analogues. The cost of materials will save a decent amount of money, which is important for some people.