INTRODUCTION
This article was born very interesting and flattering for me. The fact is that, as expected, all my colleagues know about my hobby in the field of life in a private home. Most refer to them with humor: like "a guy with oddities," while others are quite serious, read the site's materials and come up with questions, are advised. To me, of course, it's very, very nice.
So the other day my colleague came up to me and asked if I could advise anything at the expense of receiving a television signal in the distance, so to speak, from the places where this signal is caught well. When I told what I knew, my colleague asked me puzzled why I had not written an article on this matter. That's the thought of writing this article.
I want to immediately warn that I am not a specialist in the field of television and television antennas. Everything you read here is the result of my efforts to set up a normal image on my own TVs at various points at different distances from the transmitting center.
I started, as, probably, many others from the Polish TV antenna with a large square grid-reflector. I was fascinated by the mandatory presence of an antenna amplifier, which was sold together with the antenna. I remember that the amplifiers had quite a few modifications with different gain factors, designed for different removal from the transmitter. This circumstance also inspired me with certain trust and respect.
The first suspicion that this antenna is unlikely to help me, appeared very soon, when I began to experiment with it right in the room of my Moscow apartment, from the window of which, by the way, the Ostankino TV tower was visible. My first lesson was the following. The external television antenna is radically different from the room one. The latter can work better, at least in room conditions. However, as I now understand, it was possible to interpret this lesson in another way: a good indoor antenna is better than an external one.
The second tap took an important lesson immediately. It consisted in the fact that even a window glass represents a significant obstacle for a television signal. In order for the antenna to work, it must be hung outside the window. And this applies equally to both indoor and outdoor antenna options.
The following surprises began when the antenna was mounted on a pole. The first thing I did was read the instructions. To admit, I was really amazed that the antenna was required to be grounded. Since I was deeply convinced that if the antenna is grounded, then the television signal will go to the same place, namely to the ground, I had to take time to find out what, after all, is grounded in the TV aerial. And that's what I found out.
Did you notice that the television antennas are simple - with two "whiskers" and complex, like arrows or spaceships? So that's it! It turned out that the television signal is caught only by the "whiskers". All sorts of beautiful things that make an antenna similar to a spaceship, do not directly catch the signal and are grounded. Do not think that these bells and whistles are not needed, but more on this later. While we return to the notorious mustache. These "whiskers" are called a vibrator and often represent two pieces of a metal tube, located in a horizontal plane and connected to a television cable. These tubes can be folded into an ellipse, there is not much difference. By the way, everything matters here. Judge for yourself. The "shoulders" of the vibrator should indeed be tubular. I did not find out about their "correct" diameter, but I'm sure that also matters. The tube material should conduct electricity well. Thus, iron pipes will work worse than aluminum ones, and aluminum ones will be worse than copper ones. To tell you the truth, usually the antennas are made of aluminum tubes with a diameter of about 10 mm. I suspect that these tubes provide the necessary compromise on the strength of the structure, its weight and price.
Go ahead. The "whiskers" or "shoulders" of the vibrator should be located exactly in the horizontal plane, since in our country the television waves have a horizontal polarization. And, finally, the most important thing. "Shoulders" or "mustaches" must be strictly defined length. This length depends on what TV channels you are going to catch from the air. The larger the channel number, the shorter the mustache must be. The length of the "mustache" strictly depends on the wavelength. I deviate from the narrative style of the "teapot" for "dummies" that I have chosen in this article. I note that such an antenna design is called a half-wave vibrator, which means that the length of the whisk is exactly half the wavelength of the broadcast. Further I will not tell you anything, since I forgot school physics for a long time, and I do not remember how to translate Hertz into meters. I only remember that it is possible and, even, not difficult. At least, I very quickly found on my antenna two sets of "whiskers." Some long ones are designed for receiving television channels from the 1st to the 12th, while others are short - designed to receive channels of the decimeter range. In addition, I still realized that this antenna simply can not work as I need, since the tubes from which the vibrators are made are very thin and made of no material from which it is still clear and which have serious design flaws that can not be leveled even the most powerful antenna amplifier. In short, everything turned out exactly as I expected, that is, this cheap antenna did not give me the opportunity to increase the quality of the received signal and the number of programs received. Very soon I went to the market for a new antenna.
In the market, "raping" a large number of sellers in my company method, I learned everything I needed and report it to you.
Let's start with the coolest option. We have three absolutely different antennas. The first is for the range of 1-12 channels, the second for the range of 6-12 channels and the third for the decimeter band. Each antenna is created and tuned strictly to its range. Each cable descends from each antenna. Cables are connected to a rather complex electronic device, which performs several functions at once. First, the amplification of signals. The most advanced devices are able to regulate signal amplification through channels. Secondly, the summation of the signal from several sources. You only need one cable to plug it into the TV!
Why amplify the signals through channels? Everything is very simple. Different channels have different intensity initially. For example, the first channel is stronger than the sixth simply because the transmitter on the first channel is different and more powerful. And the RTR channel, as I suspect, is generally broadcast not from Ostankino, but from Shabolovskaya. Thus, the channels differ in intensity from broadcasting, interference, and therefore some channels need to be further amplified, while others do not, or less. On the other hand, if we increase the already strong channel, we will get the opposite effect and the image on this channel will not be perfect.
The described antenna complex allows to obtain an ideal image of all possible channels at a considerable distance from the transmitting antenna. I have an acquaintance who has this system and looks at all possible channels in excellent quality at a distance of 75 km from Moscow.
Unfortunately, it is better to assign such a system to specialists. And pleasure is not cheap.
The next option is the use of combined antennas. Such antennas usually have two vibrators, designed to receive signals from 1-12 and decimeter channels. In such antennas, the signal is summed up without the use of electronic devices directly on the antenna. To do this, we use a device similar to the "crab", which we use to connect several TVs to one antenna. Here it is worse already that with such passive summation the signal is weakened. Next, we need to amplify the signal already broadband, and this already in most cases excludes the option of an ideal reception of all possible channels. Some channels will show better, but some worse. However, this option is quite viable. Just on the agenda comes the question of analyzing the correlation between price and quality. It is possible that the quality of the image in this case will suit you. By the way, the theory at this stage is almost over. Let's move on to practice.
SELECTING AN APPROPRIATE ANTENNA
Here in the foreground is the choice of antenna. If for you the question of quality comes first, and the question of price at the last, then you should hire a firm that will come to you and do everything. This is a great option. I like him more than anyone else, but for the time being I still have to remember the anecdote about desires that do not always coincide with the possibilities, so consider other alternatives.
If we decided to do without the services of specialists, we must correctly choose a combined antenna. Remember, I talked about the details that make the antenna beautiful and similar to a spaceship? I also said that all this beauty should be grounded? So that's it! This beauty serves to amplify the signal by the antenna itself. Transverse parts that are located on the horizontal axis before the receiving whiskers are called "directors", and the delicate detail forming a focusing surface located behind the vibrator and making the antenna similar to the searchlight is called a "reflector". "Reflectors," as well as "directors" may be several. All of these additional details of the crane are important. The more of them, the more the antenna itself is longer and more complex, the better reception, and the more expensive the antenna itself. In my experience, the length of the antenna basically affects the reception quality. You can see for yourself whether the antenna gain, its length and price depend. The fact is that in the instruction of any decent antenna the coefficient of its amplification in decibels (db) should be indicated. It should be a characteristic of the antenna, not its amplifier, if it is included. For indoor antennas, this coefficient may be even less than unity. For antennas stronger - can be 2.3, even 5 dB. The gain factor of 10 dB characterizes already very complicated and expensive antenna, which will work at a significant, 100 - 120 km from the transmitter.
The following diagram shows the different antenna variants. Note that they are all built according to the same principle "Reflector" -\u003e "Vibrator" -\u003e "Director". However, only "Vibrators" have the same appearance, the other details can be completely different. Apparently, the choice of this or that configuration is the result of time-consuming calculations and experiments, to which we, I mean teapots, are not capable.
Configurations and elements of television antennas
However, in increasing the number of elements and the complexity of the antenna there is a downside. The main disadvantage of the complication of the antenna is that it becomes more directional. On the other hand, aiming for a transmitter from a distance of 100 km can be quite a big problem. Therefore, you should always remember about this possible inconvenience and choose the antenna is not the most difficult, but, say, adequate to your distance to the transmitter.
Since the antenna is supposed to be grounded, the method of fixing it to a metal tube itself suggests itself. Taking into account the fact that the antenna needs to be fastened as high as possible, the following antenna antenna device can be proposed. The length of the water pipe is 2 inches in diameter and 3 meters in length, the length of the pipe is 1/4 in. And 3 meters in length, and finally the length of the pipe is 3/4 inches and so long that you can lift the whole structure later. Splice the pieces suggest on the thread using adapters from one diameter to another.
It is better, of course, to use pipes from the landfill or construction sites that have been left after the heating system has been replaced. So you do not have to cut the threads on them, which can be both hard and expensive. Since the antenna will be fixed to the pipe with a metal clamp, the pole itself will need to be grounded and it will not be necessary to conduct the ground wire from the antenna itself.
With a grounding device, use a copper wire of a decent cross section - at least 10 mm square (diameter slightly more than 3.5 mm). Remember that a small diameter wire can easily burn when passing through it a serious lightning. If you feel sorry for spending on this case copper wire, then any other should be a much larger diameter. For example, you can use a 10 mm diameter armature. You can read about the grounding device.
What other details have remained? To begin with, serious antennas are sold without those poor amplifiers that are attached to the antenna itself. You can detect the characteristic boxes on the antenna, but they only have cable fixings. Such antennas are designed to use more serious amplifiers that are installed in the house, rather than on the antenna.
The antenna cable must have a wave impedance of 50 ohms and it must be "thick". The central wire must be solid, and the shielding braid must be braided and sufficiently dense. If the wire offered to you on the market differs from what I described above, please note that this is likely to be a wire not intended for use with a television antenna, and the image in this case may be seriously affected.
Now the issue of wiring from the antenna to several TVs. For such wiring, special "crab" devices are used. Keep in mind that with the help of such passive devices it is possible to dilute the signal without any appreciable loss of quality by more than two TV sets. If you want to build a signal on a large number of televisions, say at 4, you should use special electronic devices, in fact amplifiers. Use of such devices should be consulted with sellers. Just keep in mind that there are so many different types of such devices and you should not buy them where their choice is small or the seller can not clearly explain how one device differs from the other.
Another subtlety concerns the fastening of the longest whisk antenna to the horizontal base. At me, for example, on these mustaches sit birds and mustaches often break. This is very unpleasant, since reception of conventional meter channels deteriorates and it is necessary to lower the pole and repair the antenna. When my mustaches broke off for the first time, I made a horizontal roost over the antenna for birds, but it did not help and broke off again. In addition, it is not clear how the presence of such a perch affects the reception of television channels. So I had to make additional strengthening brackets for the mustache. In fact, later it turned out that some manufacturers include such amplifying brackets in the design of their antennas and we, ordinary people, do not have to think about it. So, if you have seen a large number of crows and / or pigeons better to be safe and find an antenna in view of this circumstance.
And the last. In the instructions to the antenna, it can be indicated that the antenna is also designed to receive the (fm) broadcasting. I want to upset you. You will not be able to use your TV antenna to improve the reception of your receiver (fm). There are two reasons for this. The first and the main is that the polarization of radio waves differs from the polarization of television waves. This suggests that if you want your TV antenna to catch anything in the air, you need to at least rotate it horizontally 90 degrees so that the whiskers are not horizontal, like wings, but vertically like a sail and the keel of the ship. After that, you still have the problem of matching the antenna and the receiver. The issue of harmonization is extremely dark for me. This clearly does not belong to the kettle. In appearance, a tiny transformer or choke is responsible for matching, representing several turns of wire on a tiny ferrite ring. In short, try to turn the antenna to start. If the reception does not improve, I advise you to buy a special antenna. I personally did so, resulting in an ideal reception of all possible music and news in the uq and fm range.
By the way, but do you know how different from fm? Many, I'm sure, will say that the UK is our Russian range, and FM is a foreign band. This is not entirely correct. The fact is that these two terms mean completely different things and are meant to be used together with each other. The term "VHF" refers to the wavelength and is translated as ultrashort waves, that is, a range of waves having a wavelength that is shorter than "short" waves. In this sense, both the Russian and foreign ranges are "VHF". Now "fm". This term refers to a method of modulating a signal. Here, too, they are the same with us. Long, medium and short waves are transmitted by amplitude modulation (am or am), and all ultrashort waves are transmitted by frequency modulation (fm or chm). Hence our range is designated as "uqv chm", and their, bourgeois, as "fm". However, we must somehow distinguish our chm from their fm. So let the existing terminology remain.
Let's sum up. If your home is not far from the transmitting antenna, say up to 35-40 km, I think that you will have a good passive antenna, that is, without an additional amplifier. On a sufficiently long pole and following the instructions, such an antenna will provide you with a view of all channels of meter and decimeter bands. If you need to amplify a particular range, or dilute the signal immediately on multiple TVs, you should install an antenna amplifier. And we will make a reservation at once that those microscopic amplifiers of 5-6 parts that are put on the antenna are unlikely to help us. If your home is located at a significant distance from the transmitter, say, more than a hundred kilometers, you will have to undertake just a titanic effort to passively look at the majority of transmitted channels. You can hardly watch all the channels at all, and the quality will be, to put it mildly, not ideal. In this case, perhaps you should pay attention to local channels, among which, I am sure, there are also relayed central ones.
We, the dummies should buy the antenna in the store, since the creation of complex antennas is a matter of serious research of experiments and investments. Entire institutions work on the issue of improving the television reception and more than one thesis has been written.
And finally the pictures of my own antennas. Which one is television - it should already be clear. Right with neighbor pigeons. Click the picture with her. On a larger version, fragments of reinforced fastenings are better seen.
The "reinforcement" of the mustache is visible
A real FM antenna that makes reception of radios just perfect
That's all. I hope that was useful to you. If I made an inaccuracy, or missed some aspect, write, correct, add ...
Specialists in the field of television reception, please write comments. Do not forget only that the article was conceived as an introductory and complicate it with incomprehensible terms and concepts I do not want.
In the modern world it is difficult to imagine life without television and the Internet. Without a TV, at least, boring, and the Internet is sometimes just necessary for life: work, communication, news, etc.
Often, the owners think about the Internet and television after the complete decoration of the premises, and this in turn brings a number of problems in the installation, as a result, the cost of installation can significantly increase, the interior and exterior of the house suffer, some problems seem almost impossible to solve.
Therefore it is very important to design and carry out the installation of low-voltage networks (TV and Internet) before the finishing works. Designing low-voltage networks requires a careful approach, because The errors can then be irreparable.
The Internet. If the house is located within the city limits, then, most likely, there will be no problems, you will easily get several excellent offers from local providers and will be able to choose the most advantageous offer for them. But if the house is located far from the city, then the choice you will be modest: satellite Internet, 3G / 4G Internet from mobile operators, the Internet via Wi-Fi or radio. Let's take a closer look at each of the options for connecting the Internet in a country house.
Satellite Internet . Organized by installing a satellite dish and modem. Reception and transmission of traffic occurs through a satellite channel.
Pros:
- You can connect anywhere in the Russian Federation, where another type of connection is not available;
- the ability to connect a static (white) IP address (allows you to easily configure remote video surveillance and management of automated systems).
Minuses:
- high cost of equipment and installation;
- high monthly fee;
- relatively low by modern standards, speed (usually up to 8 Mbit / s for reception and up to 2 Mbit / s for return);
- Long Ping (uncomfortable to play online games).
3G / LTE internet. It is organized by installing and configuring an external directional 3G / 4G antenna and other equipment. Reception and transmission of Internet traffic occurs through cellular communication mobile operator.
Pros:
- a fairly high speed Internet channel;
- relatively low cost of equipment and installation;
- affordable tariff plans.
Minuses:
- You can connect with a network operator;
- No, without limit tariffs (there is either a limit on traffic, or start to cut speed).
Internet via radio or Wi-Fi. This type of connection to the Internet is devoid of many disadvantages. There are no restrictions on traffic, the cost of equipment and subscription fee is not much higher than the cost of payment for mobile operators, the connection speed is comparable to the city's wired operators. But this type of connection is available only if there is an appropriate operator and near it base station (usually up to 30 km from a station located in a city or a large regional center).
TV. Possible options: cable (analog and digital), IP TV, terrestrial (analog and digital), satellite. The first two options can be considered only if your house is located within the city. For the home located outside the city, the most commonly used systems are the reception of air TV, satellite TV and hybrid (terrestrial and satellite).
Ether TV. Analogue will not be considered, in the 21st century we still live. Digital terrestrial TV allows you to view 10 to 20 or more channels in good quality. The number of channels depends only on how many channels the broadcasting television station (tower) broadcasts is spreading on the territory where your house is located.
Satellite TV . Reception channels is possible almost anywhere in the Russian Federation, the main thing is that in the direction of the satellite dish there were no barriers: tall, dense trees, tall buildings located close to your home. Such obstacles can interfere with the passage of the signal from the satellite to the satellite dish. At the moment, the following operators operate on the territory of Russia: NTV-Plus, Tricolor TV, Orion Express (Telecard, Continent TV), MTS. The antennas of NTV-PLUS and Tricolor TV in the central part of the Russian Federation are directed to the south, the signal from the satellite is strong and stable, the satellite is located high above the horizon, therefore satellite antennas of these operators can be installed in most country houses, problems arise only if the house is located in the forest . Plates MTS and Orion Express in the European part are sent to the southeast, the signal is stable, but the satellite is located close to the horizon, so these antennas are more demanding to the installation site. The distribution of the satellite signal through the rooms of the house is not made by means of splitters (as in air TV), so it is important that the design and installation are done by professionals.
Combined TV reception systems in a country house. Combine the ether and satellite TV, design and installation is also better to entrust to professionals.
The house in the country is primarily intended for recreation from the city bustle. In addition to clean air and the close location of nature, there must be a sufficient level of comfort. One of the important components is television.
At once it is worth noting that in the city there are several ways to get high-quality broadcast of channels. With increasing distance from the city, significant difficulties arise. Nevertheless, there are ways to watch your favorite movies or programs without interference.
When analyzing possible television communications, we can state that some of them outside the city are simply not available. For example, there are no collective antennas for reception of terrestrial television. This connection does not require the purchase of any equipment, and is characterized by its simplicity and low cost. Consequently, television in a country house can be obtained with an analog antenna or a satellite dish.
Analog signal
Viewing analog channels is becoming less popular for several reasons. Among them, the main drawbacks can be considered a small number of channels and poor reception quality. Nevertheless, such a source is still used in connection with the minimum cost of installing the antenna and easy connection.
If the number of received air channels can not be increased, then the signal quality can be slightly improved. To do this, you need to install two antennas. The first for receiving ten-meter waves, and the second for meter waves. To make such a system work, you need an antenna combiner that can bring all the signals into one cable. Most TV models have only one connector for the cable.
It should be remembered that the higher the TV antenna in the country house is, the more cable will be required. The length of the cable directly affects the attenuation of the signal. To avoid this, you need to install a television amplifier. Channel reception tuning is performed for half an hour by turning the antenna towards the TV tower and then fixing it in the most effective receiving position.
Satellite TV
Satellite TV is the next generation. The main differences can be considered high quality and a large number of channels received. If analog television allows you to view about 20 channels, then satellite is many times larger. And TV channels can be not only the post-Soviet space, but also foreign ones. Everything depends on the selected software package.
The main advantages are mobility and independence of quality from the level of signal reception or distance to the nearest city. A small visible sector of the sky will be enough for normal operation.
The fundamental difference is that there can be no bad image quality. The broadcast will either be carried out, or it will simply not be. Mobility lies in the possibility of multiple mounting or dismantling of all equipment. For example, for summer time, you can install it in a country house, but in winter, in the absence of owners to remove.
There are two possible approaches to get satellite TV. They are the opposite in terms of financial investments:
- with a subscription fee;
- without a monthly fee.
The first approach implies a lack of payment for equipment and the dish itself, but you need a monthly fee for watching the channels. The amount varies depending on the selected package and the availability of paid channels. Concerning the paid channels, it should be noted that there is no annoying advertising, and nothing will interfere with viewing your favorite movie in high quality.
Satellite TV without a subscription fee requires the purchase of all necessary equipment, and there will be no additional charge monthly. This will be possible only if you accept paid channels, which you need to negotiate with the operator in advance.
Modern equipment also allows you to view high-definition channels. HD-quality is 4 times greater than the digital image. This is very important today, because the diagonal of TV sets is increasing every year. If before, a TV with a diagonal of 70-80 cm was a rarity, but now this is almost the standard screen size.
A new approach
The state, for its part, is also trying to improve not only the quality, but also the number of analog channels being broadcast.
Thanks to the modernization of the equipment, everyone can now purchase an inexpensive set of equipment and start using the new DVB T-2 broadcasting standard. Such digital television in terms of quality is not inferior to satellite. Now more than 20 channels are being broadcast, but in due course there will be more. This is due to the fact that not all TV towers have the necessary equipment, but in the future it will be installed.
Analyzing all possible sources of television, we can say that an antenna for a country house receiving analog signals is gradually becoming a thing of the past. Recently implemented digital television standard DVB T-2 is not very competitive yet, because it is much inferior to satellite television in many respects. But, nevertheless, with stable development in the future, this will be a worthy substitute for free analog TV. At least from a financial point of view it will be more profitable than a satellite.
With sufficient funds, today it is best to connect satellite TV. Buying equipment will save you from monthly expenses and will allow you to view free channels in excellent quality. In addition, modern technologies also allow access to the worldwide Internet. Such an integrated approach is very in demand and allows you to save money, including installation of equipment.
The main drawback in the future experts believe that the fact that the most interesting free channels will begin to encode. In order to view them, you will need to purchase decoders or access cards. This, in turn, will require additional costs, which as a result will ruinously affect the popularity of satellite television.
The following video shows how simple it is at home to make an antenna for receiving a DVB T-2 digital signal:
