The all-wave television antenna receives channels that are transmitted in the meter and decimeter ranges. It can be indoor type, for installation on moving objects (car) or outdoor. In cities with high building density and in settlements remote from television towers, an uncertain signal may be observed. In such cases, it is recommended to install external all-wave antennas.
Selecting an antenna depending on the installation location
You can buy an all-wave antenna to receive DVB-T and DVB-T2 television standards. When choosing an all-wave antenna for your dacha, you must take into account that reception in the installation area may be uncertain due to a weakened signal. Therefore, think in advance about ensuring that the antenna is installed at the required height. In this case, the all-wave outdoor antenna is installed on a high mast or bracket and is provided with sufficient fixation. In places farthest from transmitters (more than 50 km), an all-wave television antenna with an amplifier should be installed. It has an increased load capacity and serves to obtain a reliable signal. It is not recommended to use it near a telecentre.
If there is a lot of interference in the form of power lines, high-rise buildings and obstacles, which are a source of signal distortion, you should use an over-the-air all-wave antenna with a good protective coefficient. In the area of a reliable signal from one all-wave TV antenna, using apartment amplifiers, you can connect up to 10 subscribers. If a larger number is required, it is advisable to install a system of 3 antennas. After reviewing the detailed characteristics of each model on the website, you are sure to find the antenna that is suitable for you.
Which antenna to choose for digital television? How are antennas different? How to supply power to an active antenna? Which antenna is better? These and other questions on the site
Hi all! Due to my line of work, I have to deal very closely with connecting and setting up antennas for digital terrestrial television.
Therefore, based on the experience gained, I have the opportunity to share how to choose an antenna for digital television and set up dvb-t2 - free 20 channels.
Quick navigation through the article
Which antenna is suitable for DVB-T2 digital television
With the advent of digital terrestrial television, many people have questions related to the choice of antenna for DVB-T2. For example!
- Can I use my old antenna, if I had one?
- Is an antenna of the “Lattice” type, also known as “Polish”, suitable for this?
- Do I need an antenna with or without an amplifier?
- if there is a question about purchasing a new one?
- Is the advertised “Key to Free TV” antenna necessary?
Let's first figure out what kind of antennas there are.
Antennas of the meter (MV) and decimeter (UHF) ranges are used to receive television signals. There are broadband antennas, this is a “hybrid” when elements of the MV and UHF bands are used in the antenna design.
These antennas are easy to distinguish from each other by size.
The MV range has longer elements. Everything is according to the name.
So in MV antennas the elements are approximately half a meter to one and a half meters in length.
And the elements of the UHF antenna are only about 15 to 40 cm long.
It is the UHF antenna that is needed for digital terrestrial television.
VHF Antenna 
Example of a UHF antenna 
Broadband antenna, MV and UHF ranges. 
Array antenna 
Broadband antenna "Hummingbird" So - To receive digital terrestrial television you need a UHF antenna, i.e. antenna with short elements. Or broadband.
Now you can evaluate whether your old antenna is suitable for receiving television in the DVB -T2 format. The only question that remains open is its serviceability and effectiveness in your area.
In addition to dividing by received ranges, antennas are also divided into...
Indoor and outdoor (External) - I think everything is clear with the application here.
And also active and passive - more on that a little later.
Well, a brief excursion into the difficult topic of terrestrial antennas has been carried out. Let's continue...
Features of television signal propagation
The distance over which the signal is transmitted in the UHF range does not have a large coverage area. It is much less than in the meter range.
For example:
If you have used a radio, you may have noticed that you cannot catch distant foreign radio stations in the FM or VHF bands, but only those nearby, local ones.
But on the other hand, you can catch a whole bunch of foreign ones in the CB or HF bands.
This is because medium and short waves, like meter ones, propagate over long distances, and ultrashort waves, like UHF, over short distances.
This disadvantage of the UHF range for digital TV is compensated by the location and number of television transmitters - by analogy with cell towers, there are many of them.
Also keep in mind that the television signal is perfectly reflected from objects encountered along the way.
This allows you to receive broadcasts when it is not possible to point the antenna towards the TV tower. Or there are obstacles to the direct passage of the signal.
Look around! Is it possible to receive a reflected signal?
So if you choose the right antenna and install it correctly, you will surely achieve success.
What else should you consider when choosing an antenna?
Conditions for receiving a television signal vary greatly in different places and these conditions must be taken into account when choosing an antenna.
Here are some factors that will determine which antenna you need to purchase and how to install it.
- TV transmitter power and
- Terrain - mountains, lowlands, plains.
- Standing nearby and blocking the antenna towards the tower are tall, dense trees.
- The presence of high-rise buildings and your location in relation to these buildings and the tower.
- The floor you live on - the higher you are, the simpler the antenna you will need.
- Possibility or impossibility of turning the antenna towards the transmitting tower.
Active and passive antennas - what is the difference?
Antennas of any type can be either active or passive.
Passive antennas are those that amplify the signal only due to their design, without the use of electronic amplifiers; such antennas are used in areas with a strong signal.
Active antenna - has an amplifier in its design; such an antenna needs to be connected to a power source.
The amplifier helps to increase the level of the received signal in areas of poor reception.
How to connect power to an active antenna amplifier, several ways
Antenna amplifiers are powered by 12 or 5 volts. But recently, more and more, manufacturers are focused on producing antennas with five-volt power supply.
And there is a reason for this! Such antennas are easier to connect for those who use a DVB-T2 set-top box.
Three connection methods
A) Use a special power supply with a separator that produces a voltage corresponding to your amplifier.
The purpose of a separator is to separate. It passes voltage to the antenna, but does not pass it to the TV socket. However, this does not interfere with the signal from the antenna amplifier entering the TV.
B) If a DVB-T2 set-top box is used. A voltage of 5 volts can be supplied directly from the set-top box. Moreover, for any amplifiers, both 5 and 12 volts.
This does not require any additional wire, power supply, etc. The voltage is 5 volts, from the antenna socket of the set-top box, directly through the antenna cable, it will go to the amplifier.
You just need to turn on this power directly from the set-top box menu. Go to the settings section and find the item “Antenna power ON-OFF”, select ON, and exit the menu (the names of these items may differ in different models of set-top boxes)
B) If you have an LCD TV with a built-in DVB-T2 tuner, then in addition to the method under letter A) you can do the following.
You will have to purchase a special adapter to power the amplifier from any USB port; first of all, consider the USB port of the LCD TV itself. But you can connect to any charger with a USB output
Which antenna to choose - let's look at examples
As you understand from all of the above, when choosing an antenna for yourself, you need to evaluate various factors.
A few examples:
Distance to the tower 5-15 km
You live in a city where there is a DVB-T2 signal transmitter. Or in a populated area, not far from the transmitter, 5-15 km.
Most likely, an indoor antenna, even the simplest one, will be suitable for you. Especially if you live above the first floor.
And being not far from the tower, even a simple piece of wire instead of an antenna may be enough.
Considering the prevalence of towers and a fairly large number of places with a reliable signal, scammers take advantage of this, offering various, essentially
Under the conditions described above, they will work well.
But keep in mind that the number of channels will not be more than that broadcast by the TV tower in your area! But not 100 or 200 as the advertisement promises.
Therefore, the question arises: is it necessary to shell out several hundred, or even thousands, for a regular indoor antenna from an advertisement?!
Here are several inexpensive, compact antenna options for conditions where there is a good signal.
Indoor antenna for places close to the tower. 
Indoor antenna for places close to the tower. Another option 
This option may work in slightly more difficult conditions than the previous two, especially the amplified version. Indoor antenna - application features
The right place for an indoor antenna is not where it will look good and stand comfortably, this is where it will receive the signal well. And these two circumstances - “look” and “accept” - do not always coincide.
Because often the best, and sometimes the only place where you can catch a signal is a place at the window facing the TV tower. Take this into account!
To solve this problem, you can add a cable of the required length, and for some antennas (for example, those in the photo above) this is not difficult.
But there are indoor antennas that have a built-in power supply in their housing. They also have a power cord for connecting to an outlet. And of course a cable for connecting to a TV.
This may seem convenient, but unfortunately this is not always the case.
Often, the place where the antenna is capable of receiving a TV signal is not at all near the TV and outlet, but, for example, near a window.
And in this case, a short power cord will become an obstacle to placing the antenna in the right place. In addition to the cable, you will also have to pull an extension cord. Basically a lot of wires.
You live at a distance of about 25-30 km or more from the TV tower.
Of course, a lot depends on the power of the transmitter.
But in general, at a distance of 25 km, a small outdoor antenna is sufficient. Like, for example, those depicted at the very beginning of this post, we mean the UHF antenna or the broadband “Hummingbird”.
In my area, from a distance of 25 km in line of sight, a passive UHF antenna with an arm length of approximately 80 cm provides reliable reception without the need to raise the antenna above two meters from the ground.
You can also receive reception using a good active indoor antenna.
In some houses, even from the first floor, if there is a window towards the tower or the ability to receive a reflected signal from neighboring buildings.
A floor above the second significantly increases the likelihood of success.
There is a simple principle on how to determine the power of an antenna - the longer the antenna arm, the greater the coefficient of its own gain, and not due to the amplifier.
Antenna for difficult signal reception conditions
For example, the active antenna in the photo below, in our area, pulls out a signal from a distance of 60 km or more. It is successfully used in the most difficult places, in houses located in deep lowlands, its length is approximately 1.7 meters, but there are antennas up to 4 meters in length.
In addition to the length, in difficult conditions or at a great distance from the TV tower, the presence of an amplifier plays an important role, i.e. the antenna must be active.
There are options for powerful antennas, where instead of one boom, three are used at once, so the ability of the antenna to amplify the signal due to the design alone is greatly increased.
And in tandem with an amplifier, this antenna becomes a very powerful trap for a television signal.
But once you’re impressed with this antenna, don’t rush to run after it. It is only needed under really, really difficult reception conditions.
In most cases, other, much cheaper options are sufficient. In addition, if the signal in your area is already strong, then the amplifier in the antenna will only interfere.
This is exactly the case when porridge can be ruined with butter. An example of this is described below.
Polish antenna array for digital television
In some cases, the “Grid” antenna can work quite successfully when receiving digital television. Especially if you are not very close to the transmitting tower.
More than once, however, I came across a situation where, using their old antenna - Polyachka (Grid), people could not get a digital broadcast signal from it.
Either at all, or the signal periodically “fell off”; the picture crumbled into cubes, and there was freezing of the image and sound. One of the digital television packages could disappear, while the other was working normally.
The problem with these phenomena is over-amplification of the signal.
There is a way out, let's consider the options...
1) Sometimes it’s just enough to unplug the antenna’s power supply from the outlet and that’s it. But this does not always help and then more serious measures are needed.
2) Reduce the amplifier supply voltage using an adjustable power supply. Or supply power directly from the set-top box, bypassing the separator of the standard antenna power supply, by installing a regular plug.
3) Get to the amplifier board, the board that is on the antenna itself, and connect everything without an amplifier.
4) Throw away this old dilapidated antenna and buy a normal UHF antenna.
P.S. New type grille.
I hope this article will be useful to someone, leave your reviews, comments, and share your experience.
P.S. If you are purchasing a new antenna, but are not sure whether it will suit you, ask your local antenna dealers.
Sometimes they are quite knowledgeable about which antenna is best to take based on your place of residence.
And agree on the possibility, if it suddenly doesn’t work, to change it to a different type of antenna. At least in my store this is possible.
Today digital broadcasting is fashionable, but not everyone dares to buy a dish. It is expensive, and another alternative has appeared. In Russia in 2009, a campaign was launched to create a national network of digital multiplexes. Channels broadcasting a dozen programs on one frequency. Each receives a frame slot and is perceived by a special receiver input (DVB - T) of a plasma or liquid crystal panel. Today the second generation of devices (DVB - T2) has been released, be careful when choosing. Which antenna is best for a TV. Digital? You will also find TVs with a DVB-S receiver.
Modern TVs
The Tale of Bygone Years began with personal computers working with digital, applying specific standards, now the epic has spread to the development of television. Information compression using Mpeg protocols, splitting, packet framing using network protocols, transmission of service data via communication channels. The first TV tuners and satellite receivers began to flood the country, like expansion cards for personal computers. Then external models began to be produced, internal interfaces for a long time boasted greater productivity. The first protocols were parallel (ISA). Today, used by internal high-performance devices such as graphics accelerators, TV tuners and satellite receivers are migrating to USB ports.
Not surprising. If external hard drives are produced, the video stream, as a rule, consumes much less traffic than typical data exchange. Know the basic composition of the equipment to receive satellite and digital broadcasts. The set is similar:
- Antenna.
- Receiver.
- If necessary, a smart card for decoding commercial channels.
We call an antenna a satellite dish or an indoor “wave channel” for horizontal polarization. The receiver is digital, the construction methods in terms of circuit design are similar. It is worth noting: unlike personal computers, which always lack integrated tools in this area, televisions do contain built-in receivers. All that remains is to connect the antenna cable. This applies to digital and satellite broadcasting.
True, the consultants talk slippery, we think the best way out is to call the TV manufacturer to find out what equipment is needed to watch the programs. Commercial stations provide a special smart card, or organize a server on the Internet that distributes the key paid in advance. In the latter case, a trial period option is available to ensure the availability of conditions for using the service and quality. Nobody forces you to take a pig in a poke. Where to connect the smart card. Ask the TV manufacturer!
TV viewing antennas
Now about the antennas. If you want to watch multiplex or satellite, you will need to know the methods of receiving the signal. Why don’t we discuss analogue channels and radio? Slowly switching to digital:
- The best antenna for a digital TV accepts horizontal polarization of the frequency range 420 - 870 MHz.
- The best television antennas for satellite broadcasting are dishes.
In case of a fire, we focus our attention; on the Internet we came across typical indoor antennas, which were called satellite antennas. It's not funny, paraboloid manufacturers will be shocked when the things can pick up the Eutelsat W4 36.0E signal! Remember once and for all, the satellite hangs over the equator, the signal will be received by an antenna with a gigantic gain of 30 - 40 dB. Digital terrestrial broadcasting catches horizontal polarization; a schoolchild will assemble the antenna with his own hands:
- you need to know the broadcast frequency;
- calculate the wavelength;
- take a piece of cable RK - 75;
- cut the screen a quarter wave from one end;
- on the other hand, install a connector for connecting to the receiver;
- The cable section is located horizontally.
The end of the fairy tale. Really simple? Now try to assemble a paraboloid yourself, equipping it with an irradiator for horizontal polarization. We believe that the issue regarding digital and satellite television is closed!
Let's talk about which television antenna is better. Take digital broadcasting, equipment will be divided into two classes:
- Directional antennas.
- Omnidirectional antennas.
The former improved when they gained confidence in which direction the signal would come from. The gain is higher, so you will achieve good results with a passive antenna. Achieved by cutting off interference coming from all directions, the sensitivity of a given direction, on the contrary, increases. A well-thought-out method ensures improved reception quality. The multipath effect, which causes ghosting and blurring of the image, disappears.
Omnidirectional antennas are suitable for those planning to receive signals from several towers. It’s easier to catch a channel, the quality may be lower (not relevant for digital television, colored squares will appear there too).
Satellite dishes deserve a stern discussion. Some paraboloids receive signals from two or more spacecraft. Moreover, broadcasting takes place at different frequencies. Two or more irradiators are installed, each aimed at a satellite. The gain drops as the squadron of irradiators blocks the view of the dish. The result is positive, but if you wish, contact the toroidal antenna setup. The irradiators are placed outside the beam path by adding one reflector, reminiscent of part of a toroid, which is why the device got its name.
Cable and receiver for digital and satellite television
Let's discuss how to improve the signal of a television antenna.
The good old RK-75 is used as a feeder. Today you will find a wire with much better characteristics. Take one with a characteristic impedance of 75 Ohms. Indoor antennas are mostly sold in stores without active amplification. It is easy to understand by the fact whether the mains or adapter wire is suitable for the device. In the case of a passive antenna, the length between the installation site and the cable should be minimal. Reduces signal attenuation. Otherwise, the best antenna for your TV will do little to help you receive broadcasts. Please note that unnecessary gain is avoided. Red and white snow will appear on the TV screen, and ghosting may occur.
The amplifier coefficient is adjusted automatically; we do not rule out the existence of models that require manual adjustment, or worse, cannot be controlled. You can use an attenuator; by the way, you can make it yourself. In the simplest case, a conventional resistive power divider. A primitive option that will reduce the efficiency of the design and waste energy. A calculator for calculating a U-shaped attenuator is posted online. We’re not sure that the device is completely suitable for our case, but it’s definitely an option!
As for the opposite case, the problem is solved by optimizing the gain. It is possible to assemble a simple circuit using transistors; it is not a fact that such a circuit, only cheaper, will not be found on the nearest market. Be careful, the equipment is sensitive; it can easily be burned by incorrect connection or poor-quality circuitry.
Let us remind you that the receiver is built into the TV at times; discuss the issue with the dealer, manufacturer, or instructions. To set up satellite equipment, you need to change a number of settings, which is done through the TV menu. And on the computer there is a special text file that includes launch parameters. No hardware re-flashing is required.
Notes
Ultimately, I would like to add that you need to choose equipment (TV) that allows you to connect to the Internet. Satellite broadcast providers provide services mostly remotely. Places restrictions. The manufacturer must know how to configure the system. It is possible that I forgot to include the opportunity. But just in case, inquire further. The process is called card sharing.
Many television antennas are made by hand. The VashTekhnik portal published relevant reviews. The best television antenna for a summer residence is, of course, homemade. Although you can bring it from the city, a half-wave vibrator is usually sufficient. This also applies to radio reception. You will find a wonderful opportunity to organize communication via walkie-talkies by installing the appropriate antenna on your home or the rear window of your car.
- do not use the one bought when your grandfather went to first grade;
- don't buy the cheapest one with virtually no braid. Choose normal ones;
- do not shorten as much as possible;
- do not make sharp creases;
- Do not roll the excess into a coil.
Even if you connect the pieces with a standard coaxial connector, the signal quality is guaranteed to deteriorate.
Using the amplifier
This inexpensive antenna for the garden gives good results. If you plan to receive only with this antenna, then its two long side “whiskers” can be unscrewed.
Wave channel
They give good results, especially for remote signal reception when it is quite weak.
Polish
Many TV viewers use the “Polish” antenna - a grid and four rows of antennae. It doesn’t matter where it was made, they used to call it “Polish”, and sometimes “mesh”. Very often it does not demonstrate the best characteristics for receiving a digital signal.
In general, for reception at the dacha , very sensitive too. If the reception of the digital signal on it in your area turns out to be normal, then you are just lucky. The amplifier of this antenna can be powered by 5 Volts, which can be taken from a digital tuner, and then there is no need to use an additional power supply.
Zigzag
indoor antenna shows good results for . Even if you paid dearly for it, the result may be zero.
If you only want an indoor antenna as an on-air antenna for your dacha, you may be “advised” to buy it more expensive and “better”. But if you hope that she will start giving you a wonderful signal in your room, then this hope is in vain. If there is a bad signal in the house, no antenna will help. External - this is the solution to the problem if there is no reception in the room.
Satellite
Remember? We're talking about ethereal, so forget about satellites. You will not receive terrestrial television in the DVB-T2 standard through a satellite tuner. You will not connect the T2 tuner to the . We receive the T2 signal from the nearest broadcast tower in the UHF range. To a regular over-the-air antenna for a summer residence, not a “dish”.
The era of digital signals has arrived. All broadcast television companies began to work in a new format. Analog TVs are reaching their end. They are still in working order and are found in almost every family.
In order for older models to successfully complete their service life, and for people to be able to use them when watching digital broadcasting, it is enough to connect the DVB-T set-top box to the TV receiver and pick up the TV wave signals with a special antenna.
Any home craftsman can not buy an antenna in a store, but make it with his own hands from available materials for watching digital TV programs at home or in the country. The two most accessible designs are described in this article.
A little theory
Operating principle of an antenna for digital packet television
Any television signal propagates in space from the emitters of the transmitting television tower to the TV antenna by an electromagnetic wave of a sinusoidal shape with a high frequency, measured in megahertz.
When an electromagnetic wave passes through the surface of the receiving beams of the antenna, a voltage V is induced in it. Each half-wave of a sinusoid forms a potential difference with its own sign.
Under the influence of an induced voltage applied to a closed receiving circuit of the input signal with resistance R, an electric current flows in the latter. It is amplified and processed by the digital TV circuit and output to the screen and speakers as image and sound.
For analog models of TV receivers, an intermediate link works between the antenna and the TV - a DVB-T set-top box, which decodes digital information of an electromagnetic wave into a normal form.
Vertical and horizontal polarization of digital TV signal
In television broadcasting, state standards require electromagnetic waves to be emitted in only two planes:
- horizontal.
In this way, transmitters send emitting signals.
And users simply need to rotate the receiving antenna in the desired plane to maximize the power potential.
Requirements for a digital packet television antenna
TV transmitters propagate their signal waves over short distances, limited by the line of sight from the top point of the TV tower emitter. Their range rarely exceeds 60 km.
For such distances, it is enough to provide a small power of the emitted TV signal. But, the strength of the electromagnetic wave at the end of the coverage area should form a normal voltage level at the receiving end.
A small potential difference, measured in fractions of a volt, is induced at the antenna. It creates currents with small amplitudes. This imposes high technical requirements on the installation and quality of manufacturing of all parts of digital reception devices.
The antenna design should be:
- manufactured carefully, with a good degree of accuracy, eliminating loss of electrical signal power;
- directed strictly along the axis of the electromagnetic wave coming from the transmitting center;
- oriented according to the type of polarization;
- protected from extraneous interference signals of the same frequency coming from any sources: generators, radio transmitters, electric motors and other similar devices.
How to find out the initial data for calculating an antenna
The main parameter influencing the quality of the received digital signal, as can be seen from the explanatory first figure, is the length of the electromagnetic wave of radiation. Under it, symmetrical arms of vibrators of various shapes are created, and the overall dimensions of the antenna are determined.
The wavelength λ in centimeters can be easily calculated using a simplified formula: λ=300/F. It is enough just to find the frequency of the received signal F in megahertz.
To do this, we will use a Google search and ask it for a list of regional TV communication points for our area.
As an example, a fragment of a data table for the Vitebsk region is shown with the transmitting center in Ushachi highlighted in red.
Its wave frequency is 626 megahertz, and its polarization type is horizontal. This data is quite sufficient.
We carry out the calculation: 300/626=0.48 m. This is the length of the electromagnetic wave for the antenna being created.
We divide it in half and get 24 cm - the desired half-wave length.
The tension reaches its maximum value in the middle of this section - 12 cm. It is also called amplitude. The whip antenna is made to this size. It is usually expressed by the formula λ/4, where λ is the electromagnetic wavelength.
The simplest TV antenna for digital television
It will require a piece of coaxial cable with a characteristic impedance of 75 Ohms and a plug for connecting the antenna. I managed to find a ready-made two-meter piece in the old stock.
I cut off the outer shell from the free end with a regular knife. I take the length with a small margin: when setting up it is always easier to bite off a small piece.
Then I remove the shielding layer from this section of the cable.
The work is done. All that remains is to insert the plug socket into the connector on the TV signal set-top box and direct the bare wire of the inner core across the incoming electromagnetic wave, taking into account horizontal polarization.
The antenna should be placed directly on the window sill or secured to the glass, for example, with a piece of tape, or tied to the blind mount. Reflected signals and interference can be shielded with a strip of foil located a short distance from the central core.
Such a design can be done in literally ten minutes and does not require any special material costs. It's worth trying. But, it is capable of working in an area of reliable signal reception. My building is screened by a mountain and a multi-story building. The transmitting television tower is located at a distance of 25 km. Under these conditions, the digital electromagnetic wave is reflected many times and is poorly received. I had to look for another technical solution.
And for you on the topic of this design, I suggest you watch the video by the owner of Edokoff “How to make an antenna for digital TV”
Kharchenko antenna at 626 MHz
To receive analogue television signals of various wave frequencies, the design of a zigzag broadband antenna, which does not require complex manufacturing, worked well for me before.
I immediately remembered one of their effective varieties - the Kharchenko antenna. I decided to use its design for digital reception. I made the vibrators from a flat copper bar, but it’s quite possible to get by with round wire. This will make it easier to bend and straighten the ends.
How to determine the dimensions of a specific antenna
Online calculator
Let's use the all-knowing Google search. We write on the command line: “Calculation of the Kharchenko antenna” and press Enter.
We choose any site you like and perform online calculations. I went into the first one that opened. This is what he calculated for me.
I presented all his data with a picture indicating the size of the Kharchenko antenna.
Manufacturing of antenna design parts
I took the information provided as a basis, but did not accurately maintain all the dimensions. I know from previous practice that the antenna works well in the broadband wavelength range. Therefore, the dimensions of the parts were simply slightly increased. The half-wave of each harmonic of the sine wave of the electromagnetic TV signal will fit into the arm of each vibrator and will be received by it.
Based on the selected data, I made blanks for the antenna.
Vibrator design features
The connection of the ends of the figure eight busbar is created in the center at the bending stage. I soldered them with a soldering iron.
I created it according to the “Moment” principle, made it with my own hands from old transformers, and has been working for two decades. I even soldered 2.5 square copper wire with it in thirty-degree frost. Works with transistors and microcircuits without burning them out.
I plan to describe its design in a separate article on the website in the near future for those who also want to make it themselves. Follow publications, subscribe to notifications.
Connecting the antenna cable to the vibrator
I simply soldered the copper core and braid to the metal of the figure eight from different sides in its center.
The cable was tied to a copper bar, bent into a loop in the shape of a semi-square vibrator. This method matches the resistance of the cable and antenna.
Screening grid design
In fact, the Kharchenko antenna often works normally without signal shielding, but I decided to show its manufacture. For the base I took a wooden block. I did not paint or varnish: the structure will be used indoors.
In the back side of the block I drilled holes for attaching the screen wires and inserted them, and then wedged them.
The result was a screen for the Kharchenko antenna. In principle, it can be made of a different design: cut from a piece of frontal armor of a tank or cut from food foil - it will work approximately the same.
On the back side of the bar I secured the vibrator structure with a cable.
The antenna is ready. All that remains is to install it on a window to work in vertical polarization.
When a television receiver is located at a great distance from the transmitting generator, the power of its signal gradually weakens. It can be increased by special electronic devices - amplifiers.
You just need to clearly see the difference between the signals received by the antenna, which can be:
- simply weakened;
- contain high-frequency interference that distorts the shape of the digital sinusoid into the shape of some kind of “doodleball”.
In both cases, the amplifier will fulfill its role and increase the power. Moreover, the TV will clearly perceive and display a weakened signal, but with an amplified signal, playback problems will arise.
The waves are designed to eliminate such interference:
- high-pressure filters;
- screens.
They must be measured with an oscilloscope, and the methods of using various designs must be analyzed individually in each specific case. The antenna is not to blame here.