Problems with reception of digital terrestrial television (DVB-T2). Digital TV. Television standards DVB-T2, DVB-S2 and DVB-C
Most apartments and even private houses within any even small city have problems with the quality of reception TV signal now there is almost none, since cable television is installed almost everywhere. Most apartment buildings in cities with a population of over a million may have several cable TV operators, which gives residents a pretty good choice.
But as you move away from the city center, the availability of high-quality cable TV gradually disappears. And outside the city, as a rule, cable television completely absent.
Therefore, most summer residents are content with watching at most a few channels terrestrial television, which manages to be caught on . Moreover image quality often leaves much to be desired. Especially if the summer cottage is located far from the emitting terrestrial television station, then on the TV screen you can see a lot of interference from "snow" to "streaks" and black and white image instead of a color picture.
In most of Russia, terrestrial television is still transmitted to analog format. This method of signal transmission has one significant drawback: the signal-to-noise ratio drops significantly with distance from the emitter.
With distance from the television center, noise (interference) begins to dominate more and more over the main signal. This is precisely what manifests itself in the appearance of “snow” on the screen. If the cottage or village is very far from the transmitting station, then the noise will eventually interrupt the signal completely, and It becomes impossible to watch a TV channel at all.
Now the country is introducing the transmission of TV signals in digital format, and over time it is planned to completely abandon the transmission television programs in analog format.
What is the advantage of digital TV over analogue?
Transmission of a signal “digitally encoded” compared to direct transmission in analog format gives a number of advantages:
- Increasing the noise immunity of transmission and recording paths of television signals.
- Reducing transmitter power.
- Significant increase in the number of TV programs transmitted in the same frequency range.
- Improving image and sound quality in TV receivers.
- Creation of TV systems with new standards of image decomposition (high-definition television).
- Creation of interactive TV systems, when using which the viewer has the opportunity to influence the transmitted program (for example, video on demand).
- Function "To the beginning of transmission".
- Archive of TV programs and recording of TV programs.
- Transmission of various additional information in a TV signal.
- Select a language (more than the usual two) and subtitles.
- Extension functionality studio equipment.
- Possibility of adding radio to multiplexes
But there are also some flaws:
- Fading and scattering of the picture into “squares” when the level of the received signal is insufficient, the data is either received with 100% quality or restored, or is received poorly with the impossibility of restoration.
- Almost complete signal fading during thunderstorms.
- Even a transmitter with a power of 10 kW and a transmitting antenna height of 350 m provides reliable reception at a distance of 50 km, and as a result, the need for a larger number of transmitting centers than with analog TV (more frequent placement of transmitting antennas).
Since we are discussing from the point of view of an ordinary user mainly only image quality, then we can highlight only one main feature of digital terrestrial TV over outdated analogue:
Digital TV is very resistant to interference. To do this, the signal is encoded with some redundancy. Digital tuner will produce an ideal picture even in the presence of a lot of noise. And it will do this until the signal-to-noise ratio drops to a minimum, when the signal arrives at the very edge of the equipment’s capabilities.
That is, in analog broadcasting, as the signal level drops, you will see the picture worse and worse. IN digital broadcasting you will not notice the signal drop until the tuner is no longer able to restore the lost pieces of the image, and it “disintegrates into squares” and then disappears completely.
Types of digital television
Based on the transmission channel, digital TV can be divided into four types:
- Cable (DVB-C)
- Terrestrial (DVB-T2)
- Satellite (DVB-S)
- Internet TV (IP TV)
We will not consider cable TV and IP television in the country due to their great rarity. But satellite and terrestrial digital television broadcasting in the countryside is relevant.
Moreover, satellite DTV has been used by consumers for quite some time, and in particularly remote areas there are no alternatives to it at all. We will look at it in our separate article.
But on-air DTV began to enter the lives of gardeners and summer residents relatively recently. We’ll talk about him in more detail today.
Terrestrial digital television in the country
The terrestrial digital television network in the Russian Federation is still in the process of construction and currently available mainly near large cities. But it already covers a significant part of the dacha areas. Therefore, the issue of connection has become very relevant lately.
How to connect to terrestrial DTV?
If you want to try connecting digital television at the dacha, first you need to determine does your site fall within the coverage area of one of the DTV transmitting antennas?. The location of the site will determine how your TV receiver will pick up the digital signal.Most reliable way to find out, ask your neighbors in your dacha area, perhaps some of them are already watching TV channels in digital form. Then you can be completely sure that “the signal is reaching you.”
If no one in the area has yet heard of digital TV, then you need to try to find out whether your site falls within the boundaries broadcasting radius of a local emitting DTV station.
Coverage area
The broadcast radius of a DTV station usually lies within 20-50 km, depending on the terrain and building density. On average about 30 km is zone confident reception .
Each region has its own local organization - DTV operator, which is responsible for building and maintaining the network. On their website you can usually see the locations of broadcast stations and even coverage maps. Or you can get information from them by phone or written request.
The DTV network in the Russian Federation is being built by the Federal State Unitary Enterprise Russian Television and Radio Broadcasting Network.
Each region has a division of this organization.
You can call and find out everything by phone numbers in your region from the page.
If you are lucky and you find out that your dacha is located in the digital broadcast zone, then it’s time to decide necessary equipment for DTV reception.
Equipment
So, you already have a TV in your dacha, a plot in the DTV broadcast zone. Let's start installing digital television at the dacha. What else is needed to receive a signal? At a minimum you need an antenna.
Antenna for digital television reception
Universal HF/UHF antenna for digital TV reception
If a digital TV tower is nearby, then it is enough indoor antenna. I will say even more, I personally confidently caught a DTV signal in the city of Ufa on a meter-long piece of wire.
If the signal level is not so ideal, then you will need to install an antenna at your dacha to receive digital channels. Nowadays, most antennas on sale are well suited for this, since they support reception of signals in the decimeter range (UHF/UHF).
For example, you can install the antenna “GAL”, “Locus”, “Zenith”, “Meridian”, “Ether”, etc. I bought my antenna in Auchan for 1000 rubles.
If you know the exact location of the DTV tower, then everything is simple: point the antenna on her and that's it. Usually this is enough to catch a signal and watch digital TV without problems.
If the exact direction is not known, then you need to gradually rotate the antenna until you find the best position. Majority digital set-top boxes have signal level and quality indicator, which is displayed on the TV screen and from which you can find the best antenna position. This is usually done by two people: one person rotates the antenna, the second monitors the signal level.
When you have found the maximum possible signal level and the antenna is installed in the desired direction, you need to search for channels on the set-top box.
Setting up digital television at the dacha
The easiest way is to find the “Auto search for channels” item in the set-top box menu, and then the set-top box will do everything itself: it will find all available digital channels and number them in order.
List of digital terrestrial television channels
Now the interesting part: what channels does digital television show for free??
Since my dacha is in the suburbs of Ufa, and I am writing from my own experience, it means that I am considering digital terrestrial television in Ufa. But as far as I understand, list of channels throughout Russia will be the same with rare exceptions, so the information will be useful to everyone, and not just residents of Bashkortostan.
At our dacha the DTV shows 20 channels: 10 at each multiplex.
List of digital television channels
Here full list channels in Ufa:
1 | "Channel One" |
2 | "Russia 1" |
3 | "Match TV" |
4 | "NTV" |
5 | "Petersburg-5 channel" |
6 | "Russia K" |
7 | "Russia 24" |
8 | "Carousel" |
9 | "Public Television of Russia" |
10 | "TV Center - Moscow" |
11 | "REN TV" |
12 | "SAVED" |
13 | "The first entertainment STS" |
14 | "Home" |
15 | "TV-3" |
16 | Friday |
17 | "STAR" |
18 | "WORLD" |
19 | "TNT" |
20 | "Muz TV" |
I hope I helped you understand all the nuances of digital TV. If you have any questions, write, I will definitely try to help you.
7.12.2015, 10:58
Greetings.
It should be accepted at room temperature without any problems.
It should be, only according to words AleХ53-"level 0-30"... it turns out that weak signal there (or reflection) + maybe some local peculiarity and from 1 kW zilch flies there...
AleХ53, what antennas? Somehow I missed this moment.
7.12.2015, 14:59
AleX53, what antennas? Somehow I missed this moment.
two like this, at a height of 6-7 meters, in front there is a one-story building:
Why so close to street antennas? It should be accepted at room temperature without any problems.
7.12.2015, 16:10
I just didn’t have any problems before, even at the testing stage, I don’t think it’s about the antennas
Then I wonder what’s the matter, it turns out to be direct visibility.
Still, I would check the contacts. Your antenna looks like some kind of Logos (vibrators on the nuts?). Remove and disassemble to clean, at least the first 4 - 5 rows of short pins. Check the cable connection contacts, I don’t remember there are tabs for soldering there, in general, check and re-solder if soldered. Check the cable for damage. Somehow, even in this photo he looks very tired. The fact that the cable is black is not bad. It’s bad if it’s old, in the sense that it’s been in use for a long time. He could have “drinked” water or got pinched by accident, etc. Check the contacts in the plug.
7.12.2015, 16:23
7.12.2015, 17:30
I just didn’t have any problems before, even at the testing stage, I don’t think it’s about the antennas
Still, try an indoor antenna. A LPA like yours will be too much in such conditions. A lot of signal is also not good; reception problems are often caused precisely because of this. It’s just that no one is complaining anymore, and the equipment is working as usual, everything is fine. Which means it's on the receiving end. You can also try another console and find out what’s wrong. The second multiplex, by the way, was tested only one day before the official launch of broadcasting since it is commercial, unlike the first. The first one is still in test mode, if anything.
I was in Krestsy over the weekend. I gave my parents a number. Dancing with the antenna and trying to catch a signal on channel 51 was not successful (sometimes the signal could barely get through). But on 30 from Proletarka the signal was found at the level of 70%. I wonder why they built a tower in Mokry Ostrov at all? For whom? For residents of the village of Mory Ostrov with a population of 200 houses. I talked to my friends and they also watch from Channel 30.
After all, in Mokroy Ostrov there is only a 250 W transmitter and the antenna is on a low tower; it has a small coverage area. They did this so that there were no places not covered by broadcasting, which means that somewhere there are places where Proletarka does not reach and Mokry Ostrov is received there. All calculations were made mathematically, taking into account the terrain.
7.12.2015, 17:36
pssergey, the fact of the matter is that there are 2 identical antennas, one goes to the smart TV, the second goes to 2 TV set-top boxes via a splitter, I’m sure of the contacts/wires, because the analog shows almost perfectly (for analog), and again I say, the problem started a month ago, on all devices; It's something else, I'll ask my friends for an indoor antenna and try with it.
A LPA like yours will be too much in such conditions. A lot of signal is also not good, often reception problems are caused precisely by this
Perhaps you already wrote, when I try it, I’ll write back
7.12.2015, 19:09
It should, but according to AleX53 - “level 0-30”... it turns out that there is a weak signal there (or reflection) + maybe some local feature and from 1 kW zilch flies there...
because the analog shows almost perfectly (for analog)
7.12.2015, 20:21
Since the analog shows, and there transmitters are mostly 100 W, then 1 kW numbers should be perfectly received, taking into account much more high power, the height of the transmitting antenna and the fact itself that DVB-T2 digital TV has excellent noise immunity.
I’m also at a loss, I’d chalk it up to the consoles, they’re the same, BBK, but on Samsung it’s just a slideshow. I called a friend, he lives 300 meters from me, also the antenna is on the street, the same set-top box, the same problem, maybe it really is a damned place))
7.12.2015, 20:23
Since the analog shows, and there transmitters are mostly 100 W, then 1 kW numbers should be perfectly received
It’s just that initially it was only about numbers. There was not a word about analogue. Again, from the words, the problem started a month ago.
Now I have a question - it worked, it worked, and then suddenly there was a lot of signal? Then it’s even more interesting - on three different devices
someone has “connected” without authorization and is “leaking” the number.
7.12.2015, 20:25
5GDSH4, just now I went outside, the antennas are swaying a little from the wind - maybe because of this? The wind has been blowing strong for the last few days, maybe that's the problem
7.12.2015, 22:16
5GDSH4, now went outside, the antennas are swaying a little from the wind - maybe because of this? The wind has been blowing strong for the last few days, maybe that's the problem
The antenna doesn’t care about the wind, it can’t blow away radio waves)) Can you be more specific in what area such miracles are observed? You can use the device to measure the signal level in your area in order to objectively talk about reception.
8.12.2015, 20:06
5GDSH4, so far I have assembled a primitive frame http://www.vseprosto.net/2014/12/prostaya-...-svoimi-rukami/ the level remains at 70, which means after all you were right, the street antenna is “too much”, thank you very much !
Greetings.
Congratulations on your successful completion.
But the question still interests me. Based on the photo above, the signal level (intensity) to the outdoor antenna
9% (“parrots”). For an indoor antenna 70% (“parrots”). In fact - strong outdoor antenna gives a lower signal level, photo above. How to understand this? Those. It would be clearer if the street antenna provided 100% and at the same time the image would be glitchy.
8.12.2015, 20:19
pssergey
8.12.2015, 22:04
pssergey, I also thought about this, I’m not an expert, but perhaps the console itself processes the “excess” in this way, and displays on the display meter, it was like 0-9, 0-15, etc., in jerks. Unfortunately, I didn’t find how to see the level on TV, it’s just not in the menu, it would be interesting to see what it says there
But still, it’s convenient when setting up if you need to rotate the antenna. Install in manual mode search for the desired channel. If the indicator shows 0%, you start turning the antenna. I turned the antenna - it froze, you waited for 2-3 seconds, if the indicator was dead - 0%, you turned it a little more, again you waited 2 - 3 seconds... then bam - “quality -100”. Now you can press “search” on the remote control...
and the prefix, yes, the fic knows it, what’s programmed there... Nowadays it’s like that - blunder, oops! - Gadget! Buy it and try it!
It’s okay here at least 1.5-2 tr. and people are buying crap, tens of thousands are pouring out, but it works anyhow... and they smack their lips - “new”... with old troubles...
8.12.2015, 22:23
In my Samsung you can watch it, but only when setting up channels does this window pop up and only show “quality”.
also Samsung and also only found “quality”)
I called a friend, he had the same problem, I dug up my grandfather’s old mustache in the attic V also said everything was fine
8.12.2015, 23:25
In fact, a strong street antenna gives a lower signal level, photo above. How to understand this? Those. It would be clearer if the street antenna provided 100% and at the same time the image would be glitchy. mega_shok.gif
An outdoor antenna naturally gives a larger signal than an indoor one. If the signal level is too high, then the input stage of the set-top box is overloaded, so the indicator on the set-top box “jumps”. An example is human hearing; if you speak very quietly in a loud place, you will not hear anything. And if you shout through a megaphone, nothing good will come of it either. Likewise, the level should be moderately high. For DVB-T2 in the region of 40-70 dB, it’s a pity that set-top boxes and TVs, with rare exceptions, are not able to display it in decibels. The second indicator, the so-called “quality” most likely contains such a characteristic as MER - modulation error rate and, firstly, depends on very precise settings of the transmitter (ours comply with GOST, MER > 35 dB).
9.12.2015, 15:38
In Valdai, the 2nd package is coming again for several days. Is this permanent or will it be turned off?
9.12.2015, 16:44
It will work, it was officially launched there about two weeks ago.
31.12.2015, 13:52
Is anyone else having problems with their second multiplex???
It's buggy, until the New Year everything was fine. Now the picture freezes and that's it...
For those who have poor viewing, check your receiving antenna. Nothing has changed on the transmitting side for a long time, everything works stably.
17.1.2016, 16:35
30.1.2016, 10:14
I confirm 2 multiplex after the new year began to show worse, the signal is lost, before New Year there were no problems.
I bought a DVB-T2 set-top box. I tried to watch it, but the Friday channel stutters =\. Moreover, the signal level remains at the same level, but the quality jumps from 100% to 0%.
A familiar story, the same thing happened at first at the 2nd multiplex, only my level jumped. You just need to twist the antenna and try to move it around the room. Ideally, it should be placed near the window on the windowsill and on some kind of stand (for example, a box or a stack of books) so that the antenna looks not at the window frame, but at the window. And then twist and turn until the “Quality” indicator becomes more or less stable. And you will be happy ;)
A familiar story, the same thing happened at first at the 2nd multiplex, only my level jumped. You just need to twist the antenna and try to move it around the room. Ideally, it should be placed near the window on the windowsill and on some kind of stand (for example, a box or a stack of books) so that the antenna looks not at the window frame, but at the window. And then twist and turn until the “Quality” indicator becomes more or less stable. And you will be happy ;)
Exactly!
I have it on the windowsill at an angle of 45 degrees. to the surface of the earth. The strongest signal in this case.
Recently some of the channels fell apart and I had to put them on a shoe box.
28.2.2016, 17:40
communism
29.2.2016, 16:00
29.2.2016, 16:23
I'm looking for someone who knows TV cables. You need a total of 14-20 channels, but you don’t want to pay and sign contracts (not with anyone at least). You need to climb into the box on the landing and connect. Write to PM or here
buying a splitter and connecting is not a problem... only cable operators will see the connection and show up the next day)
Rogue
29.2.2016, 21:04
what brand or model would you recommend getting... so that you can also read everything from a flash drive?
I think the company doesn't care. All consoles are made according to the same design.
The selection principle is as follows:
1. You need a flash drive - you come and look for a set-top box with a USB connector.
2. You need a channel switch - you come and look for a set-top box with buttons.
3. You need a watch - you are looking for a watch.
4. You need an HDMI connector - look for one with such a connector.
5. If you need an analog output, you are looking for one with an output.
6. You need an antenna with power - you are looking for an antenna with power.
7. I.t. d.
The consoles are distinguished by bells and whistles, like the six or more that I listed above.
There are set-top boxes the size of a soap dish, which have no bells and whistles - I plug it into 220, and everything else is controlled from the remote control. Such consoles are the cheapest, like 700 rubles.
And then it went:
- a USB connector has been added - this is +300 rubles;
- added hours - + 200 rub.;
- added channel switching buttons - another + 300 rub.
- etc.
As a result, the cost may be 2,000 rubles. and if there are a lot of bells and whistles, then 5,000 rubles. and more.
29.2.2016, 21:25
what's the name, what's the discount?
The name, as usual, is NoName.
There is a USB connector, there is a recording from the air.
Price is about 1400.
Also, listen to the consultants there, you can learn a lot of new things, for example, that there are 20 channels in the region, but only 10 in Novgorod!
Why bother listening to them if you can read about what you are planning to buy? To receive digital terrestrial television channels, you need the following equipment: a DVB-T2 receiver (tuner), an terrestrial antenna for receiving a UHF signal, coaxial cable and, if necessary, a signal amplifier. Find out how to install equipment and set up digital television reception at home by reading our article.
Features of CETV
Digital terrestrial television (DTTV) makes it possible to receive Federal TV channels and radio stations included in the first and second multiplex in the MPEG-4 standard. Below you can find a list of these channels.The peculiarity of this type of television broadcasting is that you can watch the listed television channels in high quality. As you know, the previous generation of broadcasting - analogue terrestrial TV, is already outdated, since the broadcast picture has a low resolution, and on modern wide-screen TVs the image is very low quality and blurry. The new format of television broadcasting opens up new dimensions, giving subscribers a high-quality, clear picture and high-quality stereo sound.
TSETV broadcasting is carried out in principle, like regular broadcasting of UHF channels, only one channel includes 10 digital ones. There are only 2 such channels, they represent the first and second multiplex. To process the signal, you need a special digital terrestrial receiver - set-top box.
Equipment
Let's take a closer look at the set of equipment that is necessary to receive high-definition digital terrestrial TV channels.Required equipment:
- Antenna;
- Receiver (tuner);
- Amplifier;
- Coaxial cable;
- Cable for connecting the receiver to the TV.
To receive the CETV signal, you need a conventional decimeter antenna that receives channels in the frequencies 470–860 MHz. Antennas can be of two types: home (indoor) or external. The type of antenna must be selected in relation to the distance from the TV tower (repeater).
A home antenna is only suitable in cases where there is a TV tower in your city, at a distance of no more than 15 km from your home. In this case, you can get by with an indoor antenna. If your distance to the TV tower exceeds 15 km, then you must use an external antenna.
In the store household appliances or radio electronics, decimeter antennas for DVB-T2 will definitely be available. Buy special antennas that are designed to receive UHF signal, they are designed according to all the rules of radio physics and will provide high-quality signal reception.
Talk to your neighbors, probably some of them watch CETV, find out what antenna they use and what the level and quality of the signal is.
If in doubt, buy an external antenna.
Receiver (tuner)
The first thing you need to do is choose a receiver. A receiver is a special set-top box for a TV., as mentioned earlier, which processes the signal and sends it to, setting up channels and switching them is also done through the receiver. Today there is a fairly wide selection of receivers on the market for receiving DVB-T2 channels.
As for the choice, they are all almost identical and simple; choose a device based on availability additional functions: functionality and design of the menu, as well as the availability of connectors for connecting to a TV.
In some modern TVs, from the middle and premium segments, there are models with a built-in DVB-T2 tuner, thanks to which you do not need to buy a receiver, but simply connect the cable from the antenna to the appropriate socket and configure the channels.
If you have, then some models support installation CAM modules, including the DVB-T2 module. Thus, you only need to install the module in the receiver, connect the cable from the antenna to the second incoming socket, and you can watch digital terrestrial television channels along with satellite ones.
Amplifier
Majority decimeter antennas(both indoor and outdoor) include a built-in amplifier, the signal from which is amplified by the receiver, which is quite enough for reliable reception if the antenna type is chosen correctly.
Let's consider cases when a separate signal amplifier is needed. Using a DVB-T2 receiver, you can check the signal level; to do this, you need to enter the settings and the corresponding scale will be displayed there. Connect the antenna to the receiver - if the signal level is around 75% and the picture quality is quite satisfactory, then an amplifier is not needed. When the signal level is lower and the picture is noisy, it is recommended to install an amplifier.
Coaxial cable
This is normal tv cable, which transmits the signal from the antenna to the receiver. We recommend purchasing a cable with a copper circuit and screen, as it is of the highest quality, which will ensure good signal transmission and long term cable operation. Pay attention to the cable braid; the stronger it is, the better, since the cable will be less susceptible to external influences: interference and destruction.
Cable for connecting the receiver to the TV
If the receiver you choose includes an HDMI connector, which is also available on the TV, then it is better to use it for connection, since this type connection provides best quality images. For this you will need HDMI cable, which can be purchased at any hardware or computer store.
If not HDMI connectors, which is somewhat bad, then use SCART, RCA and others connectors.
Installation and configuration
First, let's install the antenna. An indoor antenna is usually installed on a window. External antenna You can try installing it on a balcony or mounting it on a bracket near a window if you live near the TV tower. Lay the cable from the antenna to the receiver. If the signal is weak enough, or the TV tower is located in the other direction, the antenna must be installed on the roof of the house. Point the antenna towards the TV tower; to do this, just look at the direction of neighboring antennas.Unpack the receiver, connect the cable from the antenna to it, then connect the cable from the TV. Next, connect the receiver to power, turn it on and perform initial settings: language, time and time zone, etc.
If the model supports automatic channel scanning, then you can use it. If automatic search no, then in manual mode you need to select necessary channels two multiplexes. In regions, these channels may differ, most often these are channels 35 and 45.
Find the channel of the first multiplex and scan it, and then select the channel of the second multiplex and scan it too. The fact is that each of these channels contains its own package of 10 channels. By the way, it is in this settings menu that the signal level scale will be displayed. If the signal level is low, you can rotate the antenna, choosing its best direction, based on the scale indicators.
That's it, now you can enjoy watching terrestrial digital television.
The development of digital television is a need faced all over the world. An analog signal, of course, extends over greater distances compared to a digital signal, but the quality of image and sound deteriorates as the distance to the broadcasting antenna increases. There was only one way out of the situation - to encrypt the signal so that it could be received and processed tens of kilometers from the translator without loss of quality. So the choice settled on digitally transfer of information.
History of digital television
For more than 60 years analog television was the only means of delivering news, films, and entertainment programs to the homes of millions of viewers around the world. If the receiver, that is, the TV, is located near the repeater, then the signal and sound have acceptable qualities. When removed, it becomes necessary to amplify the signal with various antennas. The further away the repeater is, the larger the antenna should be. At a distance of 50 kilometers, these receiving antennas reach enormous dimensions, like a multi-story building. All for the sake of several channels in mediocre quality.
Finally, in 2009, after many experiments with various formats Modern digital television DVB-T2 was launched. A number of questions immediately arose. Nothing has changed for cable and satellite television users, but for recipients analog signal arose new problem. To decrypt a digital signal, you need a TV with a built-in digital signal receiving module or a set-top box. The cost of the latter reaches $50, which not everyone can afford.
The issue is partially resolved with the help of government subsidies, and perhaps in the next few years digital television will completely replace analogue.
What is needed for high-quality digital television reception?
The quality of a digital television signal, like an analogue one, depends on the distance to the repeater. The difference is that an analog picture with poor signal reception will blur and the sound will hiss. In digital television, the image will either disappear completely or will be displayed on the screen in rectangular blocks. That is for quality reception A digital television signal also requires an antenna, but not as bulky as in the case of an analog signal.
The television signal is distributed in two bands - meter (English designation VHF) and decimeter (UHF). The first does not allow the signal to propagate to long distances, its waves do not cope well with obstacles in the form of buildings and walls inside the apartment. Therefore, most channels broadcast in the UHF range. Accordingly, for high-quality reception you will need DVB-T2 for digital television.
Types of decimeter antennas
All antennas for receiving digital television are UHF antennas, as well as meter ones. Thus, they can be divided into larger groups - indoor and outdoor.
Both types of antennas can be either passive or active. The latter has a built-in amplifier, which allows it to pick up a weak signal. But it is more narrowly targeted; it needs to be directed towards the signal source. Passive does not have an amplifier, but receives a signal from all directions for its subsequent feeding to a signal amplifier in the TV.
Which antenna to choose
Before you can set up an antenna, you need to select it. A professional approach to installation involves measuring the signal level using a portable sensor. It will be very useful in areas with dense buildings, where the signal comes not only directly from the repeater, but is also reflected from the terrain or comes from several repeaters at once. After obtaining the signal characteristics, it is necessary to study the instructions for the antenna so that the quality of reception is guaranteed.
If it is not possible to use a portable sensor, then using general recommendations, you can select an antenna by trial. The recommendations are simple. For an apartment in an area with sparse buildings, a regular but high-quality indoor antenna for DVB-T2 is suitable. In areas with dense buildings, it is necessary to use a signal. In open areas, that is, in cottage villages and dachas, it is already necessary to use an external antenna. Taking the opportunity free replacement product in the store, you can independently configure several antenna models until you find the right one.
Setting up a UHF antenna
Before installing a decimeter antenna for DVB-T2 digital television, you need to configure it to receive a signal. Having connected the antenna output to a TV or set-top box to decrypt the signal, you need to point the antenna in the direction where the repeater is located. Then you need to do automatic setup channels from the device menu. The entire frequency range will be tested.
By turning on any channel, if its quality is insufficient, you can slowly rotate the antenna to find the ideal position in which the signal will be best. Typically, receiving devices show the signal level for each specific DVB-T2 channel. You should not think that in an ideal position for receiving one channel, all others will be of sufficient quality. Having configured the reception of one channel, you need to move on to the next and so on until all channels are broadcast.
If the receiver did not find a single channel during automatic tuning or found less than half, in this case how to configure the antenna? It should be rotated 180 degrees to receive the reflected signal. This often occurs in residential areas, where large number houses interferes with the passage of the signal.
In open areas, you should simply point the antenna towards the repeater and automatically configure DVB-T2 channels on the signal receiver.
Installation of a UHF antenna
After successfully setting up the channels, the result must be recorded, that is, fix the antenna in the position in which the signal reception turned out to be the best. Indoor antennas They are usually installed on cabinets and cabinets, but this is not aesthetically pleasing. Modern antenna stands provide mounting points for screws and screws that can be installed directly on the wall.
External decimeter antennas for digital television DVB-T2 are mounted on brackets or supports. The delivery kit for an outdoor antenna usually includes fasteners that will allow you to securely mount the outdoor antenna to the support. When outdoor antennas are used in apartments, they are usually mounted outside the home: on balconies or external walls. Then, as in the case of an indoor antenna, you will need to drill several holes in the wall for secure mounting.
The process of operating a decimeter antenna
A few more comments regarding the operation of decimeter antennas for DVB-T2 digital television. Depending on weather conditions (even time of day), the quality of signal reception may vary. Therefore, the antenna mount must allow for its rotation to adjust for better signal reception.
Choosing the right antenna will allow you to enjoy digital quality TV signal. The DVB-T2 network is constantly evolving, new channels are appearing. This is a great alternative to cable and satellite television, as it does not require a subscription fee.
Digital terrestrial DVB-T2 broadcasting is carried out in the UHF television range 470-862 MHz, divided into 48 channels of 8 MHz (21-69 channels). That's why in the settings digital receiver or TV, you need to select 8 MHz, 7 MHz is for countries with a different broadcasting standard, where the channel width is narrower.
Also in the settings you should select the channel number or the corresponding center frequency of the channel. Not to be confused with the image carrier frequency, this is for analog.
The UHF range has never been completely occupied by analogue channels, therefore (and not only), free channels used for transmission of digital multiplexes. On one TV channel with a width of 8 MHz you can transmit one analog channel or one digital multiplex with several digital channels. The fewer channels included in the multiplex, the higher their quality
Installing and configuring an antenna for receiving digital television yourself is, in principle, even easier than for analogue television, but you need to understand some simple things.
- Indoor antennas are only for areas of reliable reception with a good location - a high point, direct visibility to the transmitter. Indoor active antennas may slightly improve reception if not in a good location. In other cases, they will simply be an element of the apartment’s interior.
- For high-quality digital television reception, it is necessary to use outdoor UHF band antennas. The antenna itself has gain; the more elements in the antenna design (passive directors), the higher its gain. Two antennas of different designs at the same reception point will have different signal levels at the output.
- At a greater distance from the transmitter, it would be more correct to use more powerful antennas, rather than active. I love it passive antenna You can make it active at any time by supplementing it with an antenna (mast) amplifier, and there is plenty to choose from.
- Those who want to gain more insight into the issues of choosing an antenna for digital television should read on the topics: “wave channel antenna”, “calculation of UHF antennas”
- When choosing an antenna design, it is necessary to take into account the distance from the transmitter, and when installing the direction. Sometimes, if it is not possible to install the antenna on a direct signal, you can try to receive a reflected signal; with a reasonable approach, the result will always be positive. For mountainous areas, things are much more complicated.
- If you are in an area where the transmitter has not yet been launched, you can try to receive a more distant signal. Here you need to experiment with more expensive antennas and amplifiers.
- If the antenna has amplification, then the “wiring” elements are just the opposite - attenuation. All passive elements: cable, splitter, antenna sockets, connectors contribute their share of attenuation to the signal. In this case, it is necessary to remember that the signal received by the antenna will be greater than the signal supplied directly to the TV. To compensate for attenuation, amplifiers are used, but here you also need to remember that “a lot” of signal is also bad, over-amplification will occur.
- Splitter is a divider than on more We divide the parts, the less each gets. If one apple is divided among three people, then each person will lose 2/3 of the apple. Antenna sockets are not only for beauty, but also for weakening the signal.
- Any receiver, including the DVB-T2 receiver has sensitivity. Sensitivity is the signal level, from some minimum to some maximum value, with which the receiver can operate. All changes in signal level values that fall within this range do not affect the quality of the picture on the TV screen in any way(unlike analog TV). Anything less - weak signal(it is impossible to receive the entire multiplex), anything more - overamplification(again, it is impossible to receive the entire multiplex).
- The signal strength of multiplexes can be approximately estimated from neighboring or nearby analog channels. Each region has its own situation.
Actually the right approach this is to measure the signal level and calculate and/or control its attenuation.
If we take the 16th floor entrance as an example, then the main task there is not in receiving a digital television signal, but in its correct distribution throughout the home network. People encounter this same problem only in miniature in private houses and apartments when connecting several TVs.