How to make an antenna for digital television. Antenna for digital television. Common Mode Antenna Arrays

). Thus, an antenna is a kind of transmitter (receiver). In this article we will understand what antenna is needed for receiving DVB-T2 signal.

Antenna types:

By type, antennas can be divided into indoor, outdoor and outdoor antennas. long-distance reception. We are interested in antennas that able receive standard signal DVB-T2. They can be divided into two groups: indoor and outdoor. In turn, they are divided into active and passive.

Digital signal terrestrial television DVB-T2 standard is transmitted in decimeter ( UHF) range. This range(UHF) is within 470–862 MHz. In Russia, these frequencies fill the channels from 21st to 69th television channel (TVK) inclusive.

We would like to immediately make a reservation that there are no special antennas for DVB-T2 reception, all these are ordinary decimeter antennas with or without a signal amplifier. Choose An antenna for DVB-T2 reception will not be difficult. There are two main criteria to consider here: distance to the transmitter and relief terrain. Two services will help us with this:

Next, we proceed directly to the selection of a DVB-T2 UHF antenna. If the terrain of your area is more or less flat and the distance to the transmitter is no more than ten kilometers, then you regular one will do UHF antenna without amplifier. Although, if the price difference is not big, then we recommend purchasing active antenna(with an amplifier), because you can always turn it off.

Indoor DVB-T2 antennas:

As an example of a passive indoor DVB-T2 antenna, let's take the Sirius 2.0 antenna, manufactured by REMO. You can read it on our website.

As an example of an active indoor DVB-T2 antenna, let’s take the “MINI DIGITAL” antenna, from the same manufacturer “REMO”. You can also find it on our website.

Outdoor DVB-T2 antennas:

Outdoor antennas are also classified into active and passive. They must be used when the distance from the transmitter is more than 10 kilometers. It is recommended that these antennas be pointed accurately at the transmitting station.

As an example of an outdoor DVB-T2 antenna, let's take the SELENA MINI antenna, manufactured by REMO.

As an example of an outdoor active DVB-T2 antenna, let’s take an antenna made by REMO.

Outdoor DVB-T2 antennas for long-distance reception:

If the distance to the transmitting equipment is over 30 kilometers, then you will need highly directional antennas with increased sensitivity. These antennas can receive signals at a distance of up to 100 kilometers. Also do not forget that such antennas must be installed on an appropriate height.

As an example of an outdoor active DVB-T2 antenna for long-distance reception, let’s take an antenna made by REMO.

At the beginning, I would like to inform you that there are no “digital” antennas. Any UHF antenna will be suitable, specifically for Sochi, operating in the range 32 and 53 frequency channels. If you live in a place where there is direct visibility to the Sochi television center, then indoor antenna(do not choose an antenna with a built-in amplifier) and even an antenna made from a piece TV cable will suit you quite well, considering that the first multiplex broadcast on 32 channel goes with an excess level compared to the level of the second multiplex on channel 53, so we will tune our whip antenna to channel 53.

To do this, take a piece of RG-6 60-70cm coaxial cable, terminate one end with an F connector and an adapter for connecting to the antenna socket of the TV. At the other end, the central core of the cable is exposed. Based on the calculation that channel 53 is at a frequency of 730 MHz, which is approximately 41 cm, this means that we expose 41 cm of the central core (you can use half of this or even a quarter). Next, we fix our antenna directly on both sides with tape. back cover our TV, the antenna is ready!

Not all residents of Sochi live in direct visibility to the television center, than more difficult conditions reception, the higher the gain the antenna will be required. I would like to warn against the illiterate use of television signal amplifiers, the most good amplifier This good antenna, and if there is no signal from your antenna, then there is nothing to amplify. Moreover, the amplifier can also ruin what was in the antenna. The fact is that the whole city is covered with a network of towers cellular communications, and the G-2 standard uses the 900 MHz range, which easily penetrates the antenna amplifier, and leads to intermodulation distortion, which does not allow the DVB-T2 tuner to work normally, as a result of which the TV writes, “no signal.”

To avoid this, LTE filters are used, which cut out what is above 850 MHz. The first multiplex does not call special problems with its reception, as it is broadcast from many repeaters in the city: Moldovka, Ermolovka, Cossack Brod, Golitsyno, Kepsha, Kudepsta, Matsesta, Dagomys and a dozen in the Lazarevsky district.

The second multiplex can only be received from the television center of the Central District and the repeater in the village of Veseloye. To receive a signal remotely from a television center, it is necessary to use an antenna with a high gain of 16-18 dB and a channel amplifier 53 television channel. I will say right away that the amplifier cannot be assembled under amateur conditions. But you can build an antenna tuned to TV channel 53.

The 25-element “wave channel” antenna consists of a four-element reflector, a loop vibrator, twenty directors and a traverse. The antenna elements are made of wire or tubes with a diameter of 4-5 mm; they are attached in any way to the supporting boom (crossbeam), which is made of a rectangular tube with a side of 20 mm. The gain of such an antenna reaches 17 dB, the opening angle of the main lobe of the radiation pattern in the horizontal and vertical planes is 28-30 degrees. When installing this antenna, it is necessary to provide the ability to adjust the antenna not only horizontally, but also vertically, because the envelope wave always comes from above and a couple of decibels, which can be gained in conditions of poor reception, will not hurt. Antenna amplifier, preferably channel (53 k) must be installed on the mast closer to the antenna. The antenna is matched with the descent cable using a half-wave U-shaped elbow.

p.s. My father wrote the article, especially for Sochintsy :)

Today for broadcast television signals began to be used digital standard DVB-T. To receive transmissions on analog TVs You can make an antenna for digital TV with your own hands, which is connected to a special signal-converting set-top box.

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Requirements for a digital packet television antenna

To ensure signal reception and transmission to the amplifier, the antenna must meet the following requirements:

The collecting elements must be located along the axis of the waves coming from the transmitter.
Have protection against interference with a frequency close to the television signal. Sources of interference may be other radio signals, interference from operating electric motors and generators.
The antenna design should minimize signal power loss during transmission.
The antenna circuit must be oriented according to the type of polarization.

Types of TV Antennas

Antennas for receiving television signals are divided into several types, differing in the frequencies of the received signals.

The following types are widespread:

An all-wave antenna that can receive digital and analog signals. Reception distance analog signals is not large and does not exceed the line-of-sight range of a television tower.
Log-periodic antenna capable of receiving meter and decimeter waves.
A decimeter antenna designed to receive only short waves.

The author of the video, Dmitry, will talk about making a simple antenna for digital TV.

How to find out the initial data for calculating an antenna

The key parameter on which the quality of reception depends digital signal, is the wavelength of the radiation. Based on this length, select dimensions antenna whiskers. To determine the wavelength, a calculation is used using the formula λ=300/F, where F equals the frequency transmitted signal in MHz. This option is in open access and can be easily installed through any Internet search engine.

Made from a cardboard box

The simplest option home antenna, which you can quickly make yourself from available materials, is a device based on a cardboard shoe box.

For production you will need:

food grade aluminum foil;
a piece of standard coaxial cable;
masking or stationery tape;
a tube of quick-drying glue, for example, rubber “Moment”.

The manufacture of the antenna is as follows:

Cut the foil to the shape of the bottom of the box. Lubricate the box with glue and stick the foil, smoothing it evenly along the bottom.
Cut two pieces of coaxial cable 500 mm long.
Remove the cable shielding insulation from each end to a distance of no more than 25 mm.
Move the screen and twist it into a separate core.
Bend each segment into a circle shape.
Secure the sections on the outside of the box lid in the shape of a number 8 using tape. The ends of the cable should be directed towards the center of the figure eight and located at a distance of at least 10 mm from each other.
At a length of about 100 mm, strip the outer insulation of the cable that will connect the antenna to the receiver.
Twist the screen into a separate core.
Gradually remove the insulation of the central conductor until a section of bare wire with a length of about 95-100 mm is obtained.
Pierce the bottom of the box along with the foil and insert the cable inside.
Lead the wire through the cover and run it along the contour of one of the parts of the “eight” to the central part. Secure the cable.
Connect three braid strands together. Then fasten the three terminals of the central wire. Re-secure the knot with tape.
Install the plug on the opposite end of the coaxial cable.
Place the antenna in place best regards, which is determined empirically.

If everything is done correctly, the antenna will allow you to receive the main television channels in DVB format T2. The photo below shows the main stages of antenna manufacturing.

Covering the bottom with foil Laying rings on the lid Main cable supply Connection of conductors

How to make an all-wave antenna

Those who want to save on purchases can make an antenna for receiving a digital signal themselves by choosing one of the designs described below.

From coaxial cable

The simplest antenna design can be considered a piece of coaxial cable 2-3 m long, which has a plug at one end. The free end is cleared of the outer layer of insulation, the screen is woven into a separate conductor and taken to the side. Then the insulation of the central wire is cut off in small pieces. After this, the wire is placed on a window or windowsill, selecting a suitable location experimentally.

It should be noted that this design is only effective at a range of reliable reception, where the singal is quite powerful. If you are far away from the repeater or the receiver is located in a densely built area, it is necessary to use other antenna designs.

Of two petals

This version of the TV antenna is made from a pair of small metal plates shaped like an isosceles triangle and two wooden or plastic slats. Copper wire with a diameter of 2-4 mm is stretched between these elements.

Lobe antenna circuit

The pitch of fastening the wire on the slats is 25-30 mm. The triangular bases are connected to each other by soldering at a distance of 10 mm from each other, the wire is also soldered to the triangles. To connect to a television receiver it is used coaxial cable RK75. The wire screen is connected to the rail (the place is indicated by a yellow dot), and the central wire is connected to the junction of the triangles. In zones bad reception It is recommended to use the antenna in conjunction with an amplifier.

Butterfly

For more stable reception of the terrestrial television signal, a “butterfly” antenna is used. Homemade device A similar design can be used at home and in the country. It will provide good quality reception only with a stable broadcast signal.

To make a receiving device you will need materials and tools from the list:

a board with a length of at least 600 mm and a width of about 70 mm, the thickness can be any, but preferably 15-20 mm;
single-core copper wire with a conductor diameter of at least 4 mm;
screws for wood or metal and washers;
coaxial cable RK75;
plug connector for antenna;
roulette;
side cutters;
Phillips screwdriver;
wire stripper;
soldering iron with a power of 40-60 W;
solder and flux for soldering.

A do-it-yourself digital TV antenna is assembled as follows:

Mark the board that will serve as the antenna frame in accordance with the schematic drawing below. The distance between the vertical rows of holes is 25 mm. The holes are located on same distance from the edges of the board.
Cut the wire into 8 pieces of 375 mm and two pieces of 220 mm.
Remove approximately 25mm of insulation from the center of each long piece.
Bend the cables into a V shape with equal lengths. The distance between the ends should be 75 mm.
Install the V-shaped sections on the board using self-tapping screws. For tight fixation, washers should be placed under the heads of the screws.
Before tightening the screws, install additional short connectors. On short wires, it is necessary to remove the insulation at the points of contact with the V-shaped conductors.
Connect the coaxial cable to the bottom row of screws. The installation diagram is shown below.

Can antenna with protective cover

How to make a log periodic antenna

To make the frame of such a device, the following are used:

aluminum U-shaped profile with a side height of about 15 mm;
studs with a suitable diameter and length or smooth tubes and rods are used as antenna whiskers;
a small piece of aluminum tube with a diameter of 10-15 mm, which is used as a support.

The sequence of manufacturing a simple antenna is as follows:

Flatten the tube at both ends and bend it into a U shape. One flattened end should be attached to the U-shaped profile using self-tapping screws.
Make pairs of antenna whiskers with lengths of 70, 85, 100, 120, 140 and 170 mm. Cut a thread on one side.
Drill holes in the U-shaped profile to install the mustache. The distances between the holes are indicated in the diagram.
Screw a nut onto each mustache and install assembled part into the U-shaped hole.
Secure the mustache inside the profile using nuts. Place a connecting terminal under each nut, which can be factory-made or homemade from a copper conductor.
Solder the mustache outputs into a certain sequence(shown in the diagram).

Ring antenna diagram: 1 - ring, 2 - additional loop, 3 - main cable

In the form of a frame

Another option is a frame structure called a Kharchenko antenna, made of thick copper wire with a diameter of 30-4 mm.

The antenna assembly looks like this:

Cut the wire 112 cm long.
Strip and tin the ends of the wire that will be bent into loops.
Bend it in the form of two rectangles in the following sequence - a fixation loop of 10 mm, then a rib 130 mm long, then two ribs of 140 mm, two of 130, two of 140, the last rib is 130 mm long and ends with a loop that The last 10 mm of wire goes away.
Connect the loops at the ends and solder the joint.
Move this angle apart from the opposite one by 20 mm (shown in the photo below). Tin the wire located opposite the joint of the loops.
Strip the coaxial cable 20 mm for the screen and 10 mm for the central core.
Solder the leads to the tinned corners on the frame.
Make a central body from a plastic cap of a suitable size.
Place the squares of the frame with the cable into the housing and fill it with hot glue. After the glue has hardened, install the antenna in the place of best signal reception.

To calculate the parameters of the Kharchenko antenna, there are specialized online calculators that calculate all the product data.

Amplifier based on the MAX2633 circuit

To make an amplifier, you will need three capacitors with a capacity of 1 nF and a resistance with a nominal value of 1 kOhm. To power such a device it is used constant pressure from 3 to 5 V. The device does not require adjustment, but the degree of amplification is adjusted by setting a resistance of a different value (to reduce the degree of amplification, it is necessary to increase the resistance). Such an amplifier is not broadband and is applicable only for the shortwave range.

For wideband amplification when receiving a signal on long distances transistor devices are used circuit diagrams which are given below.

Amplifier on base common emitter transistor KT368 Amplifier on common base transistor KT315 Two-transistor amplifier

In progress self-assembly similar devices needs to be produced printed circuit boards with paths. When using wires to connect elements, the amount of interference increases, which will reduce the gain of the device.

For an amplifier based on KT368 you will need resistances and capacitors with the following parameters:

100 Ohm (R1 and R4);
470 Ohm (R2);
51 kOhm (R3);
1000 pF (C1);
33 pF (C2);
15 pF (C4 and C3).

The assembled amplifier is installed as close as possible to the receiver and can be used for any type of antenna. It does not need configuration and works from the source direct current with a voltage of 9 V.

For expansion frequency range Amplifiers built on a common transistor base are used. These devices also do not require additional adjustment of operating parameters.

During the assembly process you will need the following components:

51 Ohm (R1);
10 kOhm (R2);
15 kOhm (R3);
1 kOhm (R4);
The capacitors have the same rating as in a common emitter circuit.

The amplifier circuit uses a choke coil, which is wound from 300 turns of 0.1 mm wire (PEV type) on a ferrite ring.

In case of absolutely weak signal It is possible to use multi-stage circuits operating from direct current with a voltage of 12 V and built on two transistors of the GT311D type.

The amplifier circuit for long-range antennas uses:

680 Ohm (R1);
75 kOhm (R2);
1 kOhm (R3);
150 kOhm (R4);
100 pF (C1, C2, C4);
6800 pF (C3);
15 pF (C5);
3.3 pF (C6);
100 µH (L1);
25 µH (L2);
homemade choke made from 25 turns of PEV2 wire with a diameter of 0.8 mm (L3).

do not use the one bought when your grandfather went to first grade;
don't buy the cheapest one with virtually no braid. Choose normal ones;
do not shorten as much as possible;
do not make sharp creases;
Do not roll the excess into a coil.

Even if you connect the pieces with a standard coaxial connector, the signal quality is guaranteed to deteriorate.

Using the amplifier

This inexpensive antenna for a summer residence it gives a good result. If you plan to receive only with this antenna, then its two long side “whiskers” can be unscrewed.

Wave channel

They give good results, especially for remote signal reception when it is quite weak.

Polish

Many TV viewers use the “Polish” antenna - a grid and four rows of antennae. It doesn’t matter where it was made, they used to call it “Polish”, and sometimes “mesh”. Very often she demonstrates not the best best characteristics to receive a digital signal.

In general, for reception at the dacha , very sensitive too. If the reception of the digital signal on it in your area turns out to be normal, then you are just lucky. The amplifier of this antenna can operate from a 5 Volt power supply, which can be taken from digital tuner, and then there is no need to use additional block nutrition.

Zigzag

indoor antenna shows good results for . Even if you paid dearly for it, the result may be zero.

If you only want an indoor antenna as an on-air antenna for your dacha, you may be “advised” to buy it more expensive and “better”. But if you hope that she will start giving you a wonderful signal in your room, then this hope is in vain. If in the house bad signal, no antenna will help. External - this is the solution to the problem if there is no reception in the room.

Satellite

Remember? We're talking about ethereal, so forget about satellites. You won't be through satellite tuner receive terrestrial television in the DVB-T2 standard. You will not connect the T2 tuner to the . We receive the T2 signal from the nearest broadcast tower in the UHF range. To normal terrestrial antenna for the dacha, not a “plate”.

If you plan to receive only analog channels, then you will need a mast 4.5-6 meters high, on which you will need to attach 3 band antennas. It is believed that this is a rather “expensive pleasure”, because... You can’t do this without a specialist. If you are immediately focused on simple and convenient reception quality digital broadcasting(DVB-T2), then you only need 1 UHF antennas range, because DVB-T2 broadcasting digital packages(multiplexes) is carried out only in the UHF range, and in the package itself all channels of all other ranges are already broadcast.
Currently in Moscow digital broadcasting DVB-T2 is broadcast on channels: 30 (multiplex 1), 24 (multiplex 2) , 34 (multiplex 3. Is in testing mode, some TV channels have not been finally determined) of the UHF range (see frequency grid).

Since January 2015, a third multiplex has been opened in Moscow and the Moscow region(!) on channel 34, the programs in which are currently selected on tender terms. The regular programs of the 3rd multiplex are: Match! Arena, Music of the First And Life news . The list of programs that are participating in the tender can be viewed.

(!) On channel 58 (770 MHz) since October 2016, test broadcasting of an ultra-high definition signal (Ultra HD 4K) has been carried out. The signal can be received by any resident of Moscow and the surrounding Moscow region if they have a TV that supports Ultra HD/DVB-T2/HEVC.

Multiplex 1		Multiplex 2		Multiplex 3
channel 30 (546 MHz)	channel 24 (498 MHz)	channel 34 (578 MHz)
Programs	Programs		Programs
1 channel	Ren TV		Match! Arena
Russia 1	Saved		My Planet, Science 2.0 Fight club
Match!	STS		History, Cartoon, Russian detective, Russian bestseller
NTV	Home		Country, Sundress
5 (Peter)	TV 3		Mom, 24_DOC, Amusement Park IQ HD
Russia K	Friday		Euronews, Trust
Russia 24	Star		Music of the First
Carousel	World		A Minor, Kitchen TV, Auto plus, India TV; HD Life, STV
OTR	TNT		LifeNews
TVC	Muz TV		Our football (temporarily encoded)

You can select the receiver type.

Device for maximum fine tuning digital terrestrial (DVB-T/T2) antennas.

Long-range DVB-T2 antennas

Balcony antennas DVB-T2


AURA
		Compact antenna for receiving television signals in the UHF range with built-in LTE filter(above 790 MHz). Helps avoid negative impact interference from LTE/4G cellular networks on receiving equipment and ensure a more uniform frequency response in the working reception band of UHF frequencies. Horizontal polarization. Minimal packaging volume and easy installation without tools. Widely used for installation on balconies in apartments for broadcasting digital terrestrial television of the DVB-T2 standard.

Price: 29 €



		Small-sized antenna with built-in amplifier +5 V. Designed to receive television signals in the UHF range. Easily installed on the wall (using a bracket) or directly on the balcony grille in apartments for broadcasting digital terrestrial television of the DVB-T2 standard.