Television in the country: a television signal amplifier as a way to improve broadcast quality. Reception of digital TV signal (DVB-T2) in extremely harsh conditions
Due to the greyhound nature of Tricolor, I decided to “finish off” digital terrestrial TV at my dacha.
The first (winter) attempt ended in failure: it worked in cold weather, but at zero and above there was not enough signal. Reasons: in summer the absolute humidity is much higher than in winter, lowland near the river and nearby forest. Let me remind you that my directional relief to the repeater gives a completely “closed interval”, i.e. the signal should not pass through... A relief with a refractive ellipse is attached. A
I bought a highly sensitive receiver (-82dBm) and moved the antenna from the house away from the forest (to the summer kitchen). Now it’s 100 meters to the forest, but it was probably 20 meters ( acute angle towards the repeater).
I bought and connected/stretched 23-25 meters of RG-6U cable.
I installed an antenna lightning arrester at the receiver input. We should probably install it at the output of the amplifier, but we won’t get around to it yet. And at the entrance antenna amplifier has short circuit By DC, so I think it’s protected well.
Result, in general, positive (compared to what it was before): at 650 MHz the signal strength is 80%, and at 722 MHz - 48%. On both, “quality” is 100%, which I don’t believe. Of course, 48% is not enough, but it works. On the verge. When the receiver warms up and as the play progresses, there are signal interruptions... Moreover, the antenna had to be very accurately aligned in the direction.
I didn’t like it and decided to “finish off” further.
I installed a second amplifier in the house in front of the receiver (an ancient one, from an old antenna).
At the same time, I had to overcome the excitation of the amplifier and the too strong signal.
A strong signal won out over splitters, which is just right for me, because I want to distribute DVB-T2 around the house.
Now both multiplexes have a signal level above 90%. And the quality... - see Note-3.
I liked it.
Lightning protection:
I attached a meter-long thick aluminum lightning rod to the top of the antenna mast, and organized it through an aluminum-to-copper adapter With his bottom part(and not from the bottom of the mast!) a copper descent to the grounding for which I bought and hammered a galvanized pipe 1.6 meters under the antenna. A steel cable was welded to the same grounding, to which it was tied antenna cable, going from the summer kitchen to the house. Copper to steel pipe - through stainless washers.
Note-1:
It is assumed that the TV (at least) and the rest are grounded, otherwise interference may form at the receiver input (up to 100-150 Volts), which, with a grounded antenna and a temporarily open antenna input, can (if they are connected) break through the mast antenna amplifier at the output. And this is not a theory, but a cruel truth of life.
Note-2:
It’s strange that my signal quality indicator is almost always 100%. I don't believe it!
Update dated July 11, 2015:
Note to those who insist that reception does not deteriorate when it rains.
The other day we had a wild downpour. So during this, the signal at 722 MHz completely disintegrated, and was added to 650...
It’s clear, because My signal-to-noise ratio is borderline. And the antenna is not the longest-range...
I scratched my back, tore up an old antenna that was lying around, made 6 directors about 14.5 cm long (this is the length of the directors of the purchased part of the antenna), and screwed them to the main antenna. After this, the signal level, deliberately roughened to 50%, rose to 65% (compared to a purchased antenna). How many in decibels, of course, is unknown...
We're waiting, out of the rain!
Update dated July 21, 2015:
Result of antenna modification:
Today we had a very heavy downpour again, both of my Tricolors (I temporarily have two antennas pointing at 36E) went off for 5-10 minutes, and my CETV didn’t turn off for a second...
Here, by amplifying the antenna itself, I raised the signal-to-noise ratio and therefore the signal was no longer “on the edge” and the effect was no longer noticeable. However, the signal level during rainfall decreased from 91% to 72% (at the minimum point).
Now the antenna looks like this:
Addition to the antenna modification results:
There were heavy rains and thunderstorms. I noticed that at the moment of a distant lightning discharge the image is disrupted for 2-3 seconds...
Note-3:
I bought a slightly different receiver from the same company for a friend and was additionally convinced that the almost constant 100% signal quality on my receiver was a fiction. This new receiver"measures" more or less normally. The quality on it (from the same antenna-feeder system) is 60-70%. By the way, its software menu and controls are different.
Apparently, I will shake the manufacturer/representative to provide a software update, which is much better in terms of convenience.
Note-4:
Forum member about static electricity during snowfall from an antenna on the 27 MHz range (copper wire vertically):
Note-5:
Instructions
Please note during installation antennas terrain characteristics. Guaranteed television reception area signal but it depends on the terrain. If possible, install the antenna at the highest point adjacent to your home. To ensure the required height of the antenna device, if necessary, use an additional mast, securely strengthening it with guy wires.
Choose the optimal reception design antennas. The requirements for it are as follows: simplicity and reliability, sufficient spatial selectivity, the ability to pass a wide frequency band, low input impedance and high coefficient gain signal A. For an area of uncertain reception, the level ratio is also of particular importance signal and to the level of interference.
If you are at a short distance from the telecentre (several tens of kilometers), use it to improve the received signal and an antenna of the “wave channel” type with a simple or loop vibrator, consisting of three elements. Antennas of this type are produced by industry, but if you have minimal amateur radio skills, you can make it yourself.
Check for correct installation antennas and configure it. To do this, select optimal ratio element sizes antennas required for admission signal and the selected stations. Correctly orient the structure in space by aiming the antenna at the broadcast center or repeater.
Use for improvement signal a special antennas th amplifier. The dimensions, design and connection method of such a device can be very different. When choosing an amplifier, pay attention to the information indicated in technical documentation frequency characteristics and noise level. Setting up the amplifier used for specific model television receiver, leave it to a professional. Otherwise, the efficiency of the device will be low.
To improve the quality of the received image and “catch” previously inaccessible channels, it is not necessary to buy a new powerful antenna. The receiving ability of the antenna depends on various external factors, on the shape and design, by changing which you can adjust the image quality.
Antenna location
Quality TV signal directly depends on the location of the antenna. Concrete walls, metal fences and structures greatly interfere with the passage of the signal, so most often it is located outside the house, on a wall or. If you know where the nearest transmitting tower is, the antenna should be pointed in its direction.
Changing the antenna design
Almost any antenna can be equipped with a special television signal amplifier. It operates on a 220 V network; you can buy the amplifier at most electronics stores. For the right choice it is important to know some parameters: noise figure (it should be as low as possible, preferably no more than 2 dB), gain Ku (calculated based on the presence of branches and its length).Most often, the antenna design is thought out taking into account standard search air signal. It can be changed using any metal object that conducts current: wire, cable, balcony dryer, central heating radiators, etc. Aluminum and copper items with a large surface area are best. Metal objects that are not in contact with the antenna, on the contrary, interrupt the signal.
Some antennas require special settings before use. You should check if the frequency range set to receive one or another signal.
Common-mode grating effect
If you take several identical antennas and space them horizontally so that the signal phases in them are the same, you can achieve significant amplification. For example, if a single antenna gives a coefficient of 7 dB, then a double antenna - up to 10 dB, consisting of four parts - up to 12 dB, etc.
Basic rules of a common-mode array: parts can be purchased or made independently, but must be the same. It is important that the “floors” and “rows” are completely symmetrical, with the same length of lines and cable jumpers. For fixation, frames made of insulating materials, such as wood or plastic, are used.
In most apartments and even private houses within any even small city, there are now almost no problems with the quality of television signal reception, since cable television is installed almost everywhere. In the majority apartment buildings Cities with over a million people 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 to watch at most a few channels of terrestrial television, which they can catch 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 being 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 if there is large quantity interference 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 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 to your dacha, first you need to determine does your site fall within the coverage area of one of the DTV transmitting antennas?. How the fish will be caught will depend on the location of the site. digital signal your TV receiver.Most reliable way Find out by asking your neighbors summer cottage, 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 reliable reception zone.
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 installation 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 most better 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.
We decided to write an article for people who do not have the opportunity to connect to cable television. This is rarely seen now, mainly in towns or villages. In such cases, you will have to use a regular television antenna, with which you can receive TV signals and watch TV. You can buy good and powerful antenna to improve the quality of the channels you watch. We’ll tell you how to strengthen the signal with your own hands at home. TV antenna, which you have at home.
How to strengthen the TV antenna signal?
Let's look at four simple and popular methods How to strengthen the signal of a television antenna at home:
Method No. 1
The easiest way is to use a television signal amplifier. With this device, which we connect to our antenna, we can strengthen the received signal. The device can be easily purchased at any store.
Method No. 2
Using more than one antenna. We take several antennas and take them outside your home, and you need to combine them. Two or more antennas that are combined together will work the same as installed antenna on high level(roof of a high-rise building). This will make it possible to make the signal stronger. The ideal option would be to mount the antenna on the roof, or at another high point - the higher, the better.
Method No. 3
You can expand (enlarge) your antenna using a regular television wire, which will significantly improve the quality of the received signal. Reduce or enlarge the piece of wire (that you attached using adhesive tape), change its location. After testing several options, you will see an improvement in the signal.
Method No. 4
Objects that can conduct electricity (metal, iron, etc.) significantly degrade the signal. All these elements greatly affect the quality of the signal your home antenna receives.
Today it is difficult to imagine our life without television. We watch our favorite programs, films, news on TV. But the quality of the television signal does not always satisfy our desires. What can be done to improve it?
First of all, of course, you can install satellite or digital television, but if this is not possible, then you can use the following tips.
What you will need
To improve picture quality if you watch TV using a regular common antenna You may need a soldering iron and alcohol-based cleaner. You will also most likely need new cable. If you watch television on a computer, you may also need programs to improve the signal quality.
What to do
Today, for those who want to watch television in high quality there are many possibilities. It could also be a setup satellite dish, and digital television connection. You can also watch TV online here. But if you are not ready to spend money on an antenna and pay a monthly subscription fee, but prefer to watch programs on TV,
and not on a computer, then there is still a way out.
First of all, you need to examine the cable through which the TV is connected to the antenna. It is necessary to make sure that there is not the slightest damage to the protective layer of the cable, and, of course, no breaks. If damage is found, or if the cable is already quite old, it must be replaced, because over time it loses its properties. If the cable was already damaged earlier and was not replaced with a new one, and an additional connection was made at the damage site, then it is better to replace it completely, because any additional connection degrades the signal quality. A soldering iron will come in handy if the cable is too short and needs to be extended. Of course, it’s better not to do this, but simply buy and stretch a cable of the required length.
To improve signal quality, you can also purchase and install an antenna amplifier. It is better to connect it via surge protector, in order to avoid the influence of voltage surges. The image quality will be better if the amplifier has a separate power supply.
If you haven't installed additional antenna in the house, but you receive the signal only using a common external antenna, then buy and install it. To do this, you need to find out where the television tower closest to your house is located and install the antenna on the side of the house that is closer to the tower.
Of course, if you live in a multi-story building, the signal quality will be better on the upper floors. Therefore, the higher you can mount your antenna, the better. This may require asking your neighbors to help you. If the antenna is already installed, you can change its direction. Of course, image quality largely depends on the TV.
If you prefer to watch TV online, the image quality can also be improved using various programs. Of course, no matter what antenna you install, it will only allow you to watch a limited number of channels. So if you want watch Trk Ukraine online television would be the best choice.
Good transmission quality makes watching TV a pleasant pastime. There are many ways to improve your viewing experience. The choice is yours!
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