How to improve the quality of a digital television signal. Analog signal amplification

Hello friends! In this post I will continue the topic of how to set up DVB-T2. Terrestrial digital TV, 20 channels for free, how to set up an antenna and enjoy a high-quality image.

If you are interested in what types digital television there are and how to choose the right TV given this variety, then follow this link and

You can ask about how to choose the right antenna for digital television

Well, right now, about how to configure the antenna and equipment to digital channels.

A little general information for a better understanding of the matter.

Currently, terrestrial digital television offers 20 television programs, and to listening to 3 radio stations. Total 23 and these channels are included in two digital television packages.

But what’s interesting is that the user does not need to separately configure all 23 frequency channels on his TV or set-top box, but only two.

P.S. Residents of Moscow and the region can enjoy more; they are broadcasting a third package, which already includes 30 digital television programs and the need to tune in three frequency channels.

To make it clearer, let's remember how this works in an analog signal? In this case, one TV channel is broadcast on one frequency channel, for example, in my region, Channel One was broadcast on frequency channel 6, the Rossiya TV channel was broadcast on channel 12, and NTV broadcasts were broadcast on channel 27 in the UHF range. And then further - One frequency channel = one television channel!

With coming digital broadcasting everything has changed!

And one of its advantages is that now not one TV channel is broadcast on one frequency channel, but ten or more at once, so to speak in a package. This is called “Package” or “Multiplex”. For example, from the television center in Belgorod on channel 43 of digital broadcasting 10 television channels and plus 3 radio stations is the first package, and on the 46 channel frequency another 10 TV channels are the second package. Thus, only two television frequencies are used, and not twenty-three. But keep in mind that if in Belgorod these are channels 43 and 46, then in another city these will be different frequencies.

There is only one thing that unites everyone, in any region these will be frequencies of the decimeter (UHF) range, and therefore an antenna is also needed for UHF. (ADDITION: Currently, some broadcasters are still broadcasting only one of the two packages, i.e. only ten channels.)

Find out on which channels Digital is broadcast terrestrial television in your region, where the transmission towers are located and whether they operate in full mode, broadcasting two packets, This information can be extremely useful for the successful installation of the antenna.

So, if you decide to organize digital terrestrial TV channels You will need:

1. A TV with a built-in DVB-T2 tuner or, if it does not have one, then you will need a set-top box for digital television, also in DVB-T2 format.
2. And of course the antenna itself, UHF range. Indoor or outdoor, depends on the proximity to the translator and the quality of the signal in your area.
3. Television cable, antenna plug.
4. Sometimes it helps to have a helper, and it never hurts to have patience and persistence.

How to find out if my TV is capable of receiving Digital Terrestrial Television

First, let's find out whether your TV is capable of receiving DVB-T2 signals without a set-top box, the fact is that not all devices are able to do this, old, non-flat TVs don’t even need to be checked, but flat LCD TVs may or may not receive . But if you know exactly what your TV is capable of, feel free to skip this part.

There are several ways: 1) (Dreary) Get the technical passport from the TV and look in the “technical specifications” section to find the presence of DVB-T2 there. Why is it boring? Look at your passport!….. Although sometimes you get lucky.

2) (Simpler) There is a tag on the TV case, on its back, with the TV model written on it, write it down or take a photo. Next you need to enter the TV model into search bar browser and add the word “Characteristics”. See examples in the photo below.

The model has been determined, we type in the search engine…….

Upon entering the site, select “ Specifications» then “Advanced” And we get where we need to be.

As you can see, this model is capable of receiving DVB-T2; it does not need a set-top box. Further designations indicate: C - digital cable, S2 - digital satellite. But we are interested in DVB-T2 and it is present, otherwise we would have to purchase an additional set-top box for digital television.

How to set up your antenna and TV for digital TV under different signal conditions

Let's look at the simplest option first: You live in the good zone confident reception signal. We have decided on the antenna, an article about this will help you. We connected the antenna to the TV and turned on auto channel search; in some models, when we go to the settings menu, the TV may prompt you to select and configure analog channels or digital choose digital. If everything went well, the TV itself will save the caught channels. You can admire the excellent image quality.

Let's complicate the situation a little. On auto-search, the TV did not catch anything, or only a few channels that were snowing. If this is so, then these are not digital channels, but ordinary analogue ones; digital television cannot go with the snow. (the fact is that on auto search, the TV can scan the entire range, both digital and analog).

Your next steps: If the auto search did not help, then It will greatly simplify the situation by knowing which TV channels broadcast the first and second multiplexes in your area. And also where and in what direction the TV tower is located from you in order to correctly point the antenna. If you don’t know this, then you can also see the desired direction of the antenna by paying attention to where the neighbors’ antennas are “looking.” Just don’t use satellite dishes as a guide; they are pointed at the satellite.

If you know the channel number, then do the following - You need to find the mode in the TV menu manual settings, do not forget to select “Digital”; it may be designated as DTV. Next, your task is to dial from the remote control the channel number on which one of the multiplexes (packages) is broadcast. IN manual mode a scale will be displayed on the screen that visually shows the signal level received by the antenna. (Sometimes there may be two scales, for example “Level” and “Quality”, refer to the bottom one)

And now, on the scale, you can see whether there is a signal from the antenna, in some cases, if there is no signal, then the indicator on the scale may behave like this: It will jump, zero percent - one hundred percent - zero - one hundred ..... etc. d. This indicates there is no signal. By changing the position and direction of the antenna, visually determine the best signal level, and this level should be stable, and if it changes, it should be within small limits, not to zero.

IMPORTANT: Please note that the result from changing the antenna position will not be reflected immediately, after about 5 seconds. So look best position stages, each time taking a short pause, observing the signal level on the scale. If the antenna is located on the street, then it will be more convenient to work here with an assistant.

When we managed to find the antenna position at which the signal is stable, we give the command to search and save channels. We repeat the search and save procedure for the second multiplex, indicating its channel number (if there is broadcasting of two multiplexes, it is not everywhere yet)

And now completely a difficult situation: You live in an area with difficult television reception. This may be due to the distance from the transmitting tower, the complexity of the terrain (mountains, lowlands, wooded areas). High-rise buildings located quite close to you and at the same time standing on the way to the transmitting tower, your antenna directed at the tower seems to “rest” against the high-rise.

In these cases, the principle of the adjustment itself is the same as described above; you need to visually determine the best position of the antenna using a scale. But the antennas used and some methods differ.

Antennas in difficult reception conditions must be used active ones, i.e. with an amplifier, also structurally having a higher gain. Typically, the longer the antenna arm, the greater its own gain.

Methods include the following: Determine if there are other transmission towers in a more favorable position for you. And try to catch a signal from them (fortunately they will be built quite tightly)

Using masts and other heights is the task of raising the antenna higher. (Effective in lowlands and wooded areas)

In built-up areas that are not very far from the tower, it is not necessary to use a powerful antenna; try to catch the reflected signal, point the antenna not at the TV tower, but in the opposite direction, at the building behind you or on the side. If it is possible to install an antenna on the roof of a high-rise building, this will give excellent results.

Antenna setup via digital set-top box

When using a digital set-top box, everything is the same as described above; it is better to set it up manually in order to see the signal level. The only difference is that the TV plays the role of a monitor connected to the set-top box via hdmi cable or RCA (tulips). This means that all settings need to be made in the set-top box, and not in the TV. Just don’t forget to switch the TV to the appropriate VIDEO or HDMI mode (depending on what connectors you used for connection)

To do this, you need to find the corresponding button on the TV remote control, in different models it can be indicated in different ways, here are some examples, separated by an asterisk: AV* AV/TV*VIDEO* SOURSE * HDMI * RECTANGLE ICON WITH ARROW IN* INPUT* In some SONY TVs The order is as follows - HOME - Settings - External inputs.

All further actions settings are made using the remote control from the set-top box, through manual or automatic search.

Do not forget that in this case we connect the antenna to the set-top box, and not to the TV.

What you need to know when choosing digital set-top box read in

Well, I hope this article can help you in connecting digital broadcasting to your home.

P.S. I decided to add them below to this article as interesting cases related to tuning antennas become available. If you have any, write them in the comments and they will definitely appear in your feed.

1. In my practice, very rarely, but there were cases when the antenna did not receive the signal at all, but as soon as I moved it literally a meter to the left or right, everything went fine, we returned it a meter back, again everything disappeared.
2. Today I encountered another incident. I'll describe it in detail. The situation is this: An old TV is on the floor, it works great through the set-top box, the indoor antenna is on the windowsill nearby, the signal level is about 70-80%. In this case, there is the following task.

You need to set up the number on the new LG LCD. I put it on the windowsill, next to the antenna that I connect to it, so what? LG does not see a signal at all, not even an ounce. Maybe it doesn’t support DVB-T2, I thought! I checked the model, no, everything is supported in order. What's wrong with the antenna? No, the old TV works through a set-top box. I'm at a loss!

I connect a set-top box to the new LG (What if!)........ There is a signal through the set-top box, but below 10% - It’s some kind of mystery why everything is fine with the old TV, but with the new one, which, even when in monitor mode, is connected through the set-top box, - television signal falls completely. 😯

After a short “Dancing around and around” It turned out!

The power supply of this LG was external and it was connected to the socket there, on the windowsill (there was an extension cord tee there). So, the OH power supply emitted such radio interference that being next to the antenna completely jammed the signal.

It was worth smashing into different sides, a few meters, the antenna and the power supply of the LCD TV, and everything immediately returned to normal. Bringing it close to the antenna again, the signal disappeared!

3. If you use an indoor antenna and your window is covered with metal blinds, then they can also seriously interfere with the signal. Keep this in mind!

Cable and broadcast systems television broadcasting are developing everywhere every year. However, despite the rapid growth of the network and the expanded capabilities of television equipment, the quality of the image on the TV screen can be poor. This is explained by the fact that the reception of a TV signal from an antenna depends on various factors: correct installation, design and shape of the device, distance to the repeater. Helps improve the quality of the resulting image stand-alone amplification device or replacing the receiver with a more powerful device. IN this review Let's look at how to strengthen the weak unstable signal TV antennas.

Before studying radio engineering innovations, it is necessary to analyze why the level of functioning of the receiver is low. Causes of noise and poor image quality may include:

• significant distance of the home from the repeater;
• incorrect;
• high level of natural noise;
• external obstacles to signal reception: high-rise buildings, trees, industrial buildings;
• cable failure;
• incorrect orientation of the transmitter;
• the presence of metal objects near the antenna that can conduct electricity;
• outdated technology.

Methods for amplifying TV antenna power

1. Change the location of the antenna. As a rule, it is directed to the side transmission tower.
2. Acquisition antenna amplifier. They are electrical devices that connect directly to the antenna and provide an impetus to improve the received signal.
3. Expand the number of antennas for a clearer image, installed at the highest place.
4. Change the device to a more powerful TV antenna.
5. Remove all objects and metal objects which may interfere with TV signal reception.
6. Check tv cable for integrity. In case of short circuits or breaks, replace it with a new one. For quality signal important .
7. Create an effect common mode antenna array(SAR). It consists in the fact that identical receivers form a complex system that operates on a common matched load so that the signal phases are the same.

Knowing how to improve a television signal, you can reduce image noise on the screen to a minimum and enjoy high-quality viewing, regardless of the distance to the television center.

Antenna amplifier

Advantages and disadvantages of antenna amplifiers

Like all radio devices, the devices have their pros and cons. The advantages of antenna amplifiers include:

• due to the operation of the device, even a weak television signal is received;
• minimum noise figure;
• improving the signal over a wide frequency range of several wavelengths.

The main disadvantages that users may encounter:

• overload of the device from powerful signals in the meter range MV (49-230 MHz);
• self-excitation of the amplifier;
• the device is susceptible to lightning currents;
• Passive losses occur at the output.

DIY antenna amplifier

You can design a simple device that amplifies your TV signal for your TV with your own hands. This device has low power consumption, does not create significant interference, and has a frequency range of up to 900 MHz. A low-voltage amplifier with a power supply of 2.7-5.5 V consumes a current of 3 mA and operates very quietly.

How to choose an antenna amplifier

To select the right antenna amplifier, pay attention to the following parameters.

1. Distance from repeater. This figure should be within 10-150 km.
2. Frequency range.
3. Signal level at the device output. The best option– 100 dB per microvolt.
4. Device gain. This indicator must be at least 40 dB.
5. The type of device for which the TV signal needs to be amplified.
6. Noise figure. It is recommended not to exceed this parameter more than 3 dB.
7. Consumption current. The optimal value is considered to be 30-60 mA.
8. Location: on the receiver or near the device.

Note! For digital television, a device with a supply voltage of 5 V is preferable. If the DVD-T2 has this parameter, you will not need to buy a power supply for the antenna amplifier.

Popular amplifiers

For improvement high-quality image Various amplifiers are sold on the radio equipment market. Gain can be adjusted in devices. Most devices have multiple outputs for connecting to multiple TVs.

Models for TV signal amplification

Models for amplification of terrestrial and satellite signals

Various factors can negatively affect the TV signal level. Modern radio technology devices help to increase it. They have a number of advantages: mobility, high gain and a large selection of models. Thanks to working together antenna and amplifier, you can watch television in good quality.

The best TVs of 2018 according to buyers

TV LG 43UJ634V

TV Samsung UE50MU6100U

TV Hyundai H-LED24F402BS2

TV LG 22LH450V

TV Samsung UE22H5600

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 will tell you how to strengthen the signal of the television antenna that you have at home with your own hands at home.

How to strengthen the TV antenna signal?

Let's look at four simple and popular ways to boost a TV antenna signal 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 other 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.

After working at your site during the day, in the evening you want to relax and watch an interesting film or evening concert on television.

But often, especially for summer cottages remote from large cities, the pleasure of viewing is sharply reduced due to the poor quality of television signal reception. In this case, more attention needs to be paid to the television antenna. Let's figure out when you might need an amplifier for a TV antenna in the country and how to choose it.

Currently, satellite antennas or terrestrial television antennas are used to receive television signals in suburban areas.

Satellite dishes

A good solution to the problem of obtaining a high-quality signal is to use a satellite dish. Satellite channels televisions broadcast television programs from satellites and do not depend on terrestrial television transmission centers. Modern satellite television covers the entire Earth. You just need to purchase and install satellite dish with appropriate equipment.

Advantages of satellite dishes:

• accept a large number of TV channels;
• reception does not depend on the terrain;
• have a low weight structure;
• do not require special maintenance.

A typical receiving satellite antenna consists of a reflector, which is a so-called dish (paraboloid of rotation) and an irradiator (receiver) installed at its focus. More often used offset antennas, in which the focus is located below the geometric center of the antenna, which increases its stability and sensitivity. The received high-frequency signal is amplified and converted, and then transmitted through cables for further conversion into a television signal.

A satellite antenna can have a diameter from 0.55 to 5 m. Depending on this diameter, the sensitivity of the antenna also changes.

To receive programs from various satellites, sets of satellite receiving systems are available. For example, satellite dish kits are sold that allow you to connect to the most popular television satellites “Tricolor” or “NTV-Plus”.

Installing and configuring a satellite dish is quite a complex job, so in most cases it is better to contact a specialized company to install a satellite dish, although this is an expensive undertaking. For example, a set satellite television“Tricolor TV” with the GS 6301 receiver costs 7,190 rubles, and with installation - 9,700 rubles.

Terrestrial television antennas

More common for country houses and cottages are terrestrial television antennas.

Terrestrial television antennas can be indoor or outdoor.

Indoor

can be used if the cottage is located close to the repeater and the level of the received signal is quite high. When receiving a signal with an indoor antenna, there are a number of features. These features include:

• weakening of the signal inside the building;
• multiple reflections of this signal from various objects.

As a result of reflections at different points in the room, the signal has different magnitudes. Therefore, when using an indoor antenna, it is necessary to determine the most effective location for its installation.

Indoor antennas come in frame and rod types. The former operate in the decimeter range, and the latter in the meter range.

External

If you are far away from the repeater, you must use an external antenna.

Main characteristics of antennas:

• operating frequency range;
• antenna radiation pattern;
• gain;
• input resistance.

The operating frequency range of the antenna determines the range in which the antenna provides all specified characteristics. The radiation pattern determines the directional actions of the antenna and is measured by the width of the main lobe at some given level. The gain shows how this antenna amplifies the signal compared to a simple antenna. Gain is measured in decibels.

Antenna input impedance varies by design and affects matching with the rest of the circuit. If this impedance differs from the standard characteristic impedance of 75 Ohms, then a special high-frequency transformer is used to match the antenna.

External antennas come in the following types:

• half-wave vibrator;
• wave channel;
• log-periodic;
• common mode antenna array.

Half-wave vibrator represents the simplest antenna with a gain of 1 dB and a figure-of-eight pattern in the plane of the antenna.

Antenna - wave channel consists of an active vibrator, reflector and large number directors, which form a narrow antenna radiation pattern.

To cover a wide decimeter range it is used log periodic antenna , consisting of a large number of vibrators of different lengths. A wide operating band in such an antenna is ensured by the fact that at each frequency its own vibrators are excited, ensuring reception of a given frequency. Other vibrators do not affect the operation of the antenna at this frequency.

Example common mode antenna array The so-called “Polish” antennas of the ASP-8 type, which were very common in dachas back in the 90s and continue to be sold today, can serve. Such an antenna is a system of omnidirectional antennas spaced apart in space. Due to the phase difference, a narrowly directional diagram is formed. The antenna covers the range of television channels from No. 6 to No. 69, has a gain of 14 dB and an input impedance of 75 Ohms.

Combined

In order to cover the meter and decimeter wavelength ranges, combined antennas are also used. For example, in antennas such as “Locus” or “Delta” a vibrator is used for the meter wavelength range, and a log-periodic antenna for the decimeter wavelength range.

Factors affecting television signal deterioration

Outside the city, even a very expensive TV sometimes produces poor image quality. The reasons for poor image quality may be the following:

• long distance of the TV from the broadcaster;
• poor quality connecting cable;
• presence of artificial or natural interference.

At weak signal Noise appears on the TV screen that is usually not visible. If they look like “snow”, then these are the noises of the TV amplifier. In order to increase the signal in this case, it is necessary to adjust the orientation of the antenna or increase its installation height. If these measures do not help, then if you are far away from the transmitter, you can try using an antenna signal amplifier.

The signal at the TV input may be weakened due to poor quality connecting cable. For example, when connecting cable sections by twisting. In any case, connections can only be made by soldering. And it is best that the cable is intact from the antenna to the entrance to the television receiver. If the cable has worked for more than 20 years, it is recommended to replace it.

If stripes, loss of synchronization, or shaking images appear on the TV screen, then, apparently, interference is passing through to the TV. This interference may be associated with the operation of household electrical appliances and with the operation of external sources, such as radio stations, cellular transmitters, sparking electric trains, and the like. If Appliances can be turned off, then you can tune out external sources by using antennas with a narrow radiation pattern.

Using an antenna amplifier

If the TV is located at a great distance from the TV broadcaster, the weak TV signal can be increased using an antenna amplifier.

Most commercially available television antennas are active. This means that they include an antenna amplifier.

An example is a Polish-made antenna of the ASP-8 type. This antenna offers several amplifier options with different gains. The type of amplifier is selected depending on the distance between the broadcaster and the television antenna.

The gain of the amplifier in the UHF range (21-60 channels) is 30-40 dB, in the meter range (1-12 channels) it is about 10 dB, and the noise figure of the amplifier is 3 dB. Power is supplied from a separate stabilized source of 12 V with a current consumption of 65 mA.

When choosing an antenna amplifier, you need to consider the following parameters:

• gain in decibels (dB);
• noise figure in dB;
• supply voltage;
• current consumption.

To reduce the influence of loss noise in the supply cable, the amplifier is mounted directly on the antenna. Power is supplied to the amplifying transistor through coaxial cable. The price of such an amplifier is only 120 rubles.

Setting up the amplifier is done by selecting the appropriate type of amplifier. At the same time, sellers usually give a couple of weeks to check the amplifier in the antenna. During this time, it is allowed to replace the purchased amplifier with another. Experience shows that sometimes when tuning it is necessary to slightly change the gain by adjusting the supply voltage. But this must be done carefully so as not to damage the amplification device.

DIY antenna amplifier

If you wish, you can assemble the antenna amplifier yourself. For example, a broadband amplifier circuit for the range 30-850 MHz using imported S790T transistors is proposed. The amplifier is a two-stage resistor-based amplifier. Each stage provides a gain of 10 dB.

The amplifier is powered from a source direct current with a voltage of 9−12 V. The circuit is designed as printed circuit board. It can be installed near the TV.

Antenna for digital television reception

In accordance with Federal program The country is transitioning to digital television. IN Lately masts of such television are installed in different parts of the country. For example, in the city of Zaraysk, Moscow region, a digital broadcasting mast was installed, with the help of which free transmission of RTRS-1 channel packages is carried out on channel 59 with a frequency of 778 MHz. The package includes 10 of the most famous channels.

In order to receive digital television at the dacha with an antenna operating in the UHF wavelength range, there is no need to upgrade it. If you have a TV with a built-in DTV-T2 tuner, no changes need to be made. In other cases, the upgrade concerns the TV, to which you need to connect the DTV-T2 tuner set-top box.

1. When receiving television programs in a country house, various interference often occurs and the image deteriorates.
2. To receive high-quality TV programs in your dacha, you must have good antenna — satellite dish or a high quality outdoor antenna.
3. To increase the value of the received signal, it is necessary to use antenna amplifiers, and to tune out interference, an antenna with a narrow radiation pattern.
4. Outdoor UHF antennas are quite suitable for receiving digital television, but for an old TV you need to connect a DTV-T2 tuner set-top box.

The following video will help you decide on the choice of antenna amplifier:

It's hard to imagine life modern man no TV. At the same time, some take full advantage of the advanced smart functionality of receivers, while others choose to watch programs and movies using the old proven method - using broadcast signals digital or analogue broadcasting. At the same time, the pleasure of watching programs is often spoiled poor quality receiving TV signals. In our article we will try to talk in as much detail as possible about the methods of strengthening them.

What determines the quality of TV broadcasting?

There are several factors that influence the quality of the transmitted image:

• The television receiver is located at a great distance from the signal repeater.
• The presence of external obstacles, both natural and artificial. These can be the walls of high-rise buildings, hills, lowlands and a large number of trees.
• Poor quality connecting cable.
• The antenna is installed in the wrong location or is poorly oriented in space.
• The presence of significant metal structures in the signal path or in the immediate vicinity of a television tower.

In almost each of the listed cases, the leading role is given to the TV antenna. If this attribute is correctly selected and configured accordingly, then there is a real chance of improving the quality of received signals and stabilizing the broadcast.

The industry produces both indoor and outdoor antennas. Where they are installed is clear from their name. Let's look at each type in more detail.

Antennas for indoor use

Portable antennas are quite affordable prices can perform their functions perfectly if the place of their use is close enough to the repeater. This means a distance not exceeding thirty kilometers. And the highest effect can be achieved when the TV tower, as they say, is visible from the window. In this case, the signals will not deteriorate due to multiple reflections from the walls of buildings.

For indoor antennas, it is customary to divide them into two categories, depending on the design features:

1. Frame. This type of antenna has an open metal frame. Their operating range is UHF (decimeter). It includes frequencies from 300 MHz to 3 GHz, but, as a rule, frequencies above 900 MHz are not used for television broadcasting.
2. Rod. “Horned” as they were popularly called. With their help, television signals are reliably received in the meter range (VHF), that is, at frequencies from 30 MHz to 300 MHz.

For effective use For an indoor antenna, you need to find a place where it will work most effectively. This means that it must encounter as many obstacles as possible on the path from the broadcaster to the receiver of television signals.

If all conditions are met, but a high-quality picture cannot be achieved, then you can try using an antenna that has active amplifier. In addition, there are also autonomous signal amplifiers, which we will discuss below.

If the user lives in close proximity to the translator, then he may have to purchase a device diametrically opposed to the amplifier, which is called an attenuator. But it serves to attenuate the signal, which helps prevent picture and sound distortion that appears as a result of a too strong TV signal.

Outdoor antennas

• Half-wave vibrators.
• Wave channels.
• Log-periodic antennas.
• Common-mode antenna arrays.

In order to cover the meter and decimeter ranges, it is recommended to use a combined solution, in which one design contains elements of several of the above types of antennas.

The quality of the received TV signal is directly dependent on the height at which the antenna is installed. A significant impact may be caused by nearby high-voltage power lines.

Depending on the type of signal amplification, there are several other types of outdoor antennas. Passive outdoor antennas belong to the class of the simplest passive devices, since their design does not contain components capable of amplifying the TV signal.

IN active antennas The signal is amplified due to the presence of a special microcircuit in them. Amplifiers can be either built into the antenna structure or independent of it.

Types of antenna amplifiers

When selecting a television signal amplifier, it is necessary to take into account its technical parameters:

• Frequency range. The majority of antennas sold on the domestic market are designed to work with local frequencies. However, there are exceptions.
• Gain. For the meter range this figure is 10 dB, and for the decimeter range - from 30 to 40 dB.
• Noise figure. The recommended size is no more than three decibels.

The secondary parameters in the selection process are supply current (from 30 to 60 mA) and voltage (from 5 to 12 V). There are also differences in the place where the amplifier is located (directly on the receiver or near it).

However, even the use of components High Quality and reliably operating equipment does not always guarantee satisfactory quality of received television programs. This indicator can be negatively affected by a low-quality coaxial cable used for connection, and poor-quality elements for its connection. It is recommended to purchase a cable that has a thick central core and a standard characteristic impedance of 75 Ohms.

In addition, sources of interference in the picture may be Appliances And external sources. The latter are most often radio stations and cellular transmitters. There is only one protection against them - antennas with a narrow radiation pattern.

Antenna reception of signals digital television broadcasting or analog is not significantly different. It’s just that for digital it is necessary to support the UHF range, provided that there is a DVB-T/T2 receiver in the TV itself. If it is not there, you will have to purchase an external TV tuner.

In conclusion, let's say a few words about satellite dishes. The diameter of their bowls can range from fifty centimeters to five meters. The sensitivity of the antenna is directly dependent on the size. Correctly installing and configuring a satellite dish is not at all easy, and therefore the involvement of highly specialized specialists is necessary to carry out this work.