Antenna for 3g modem from a can. How to strengthen the Wi-Fi signal with your own hands

Andrey Baryshev, Vyborg

A large number of wireless Internet users have to deal with the problem of low connection speed. This problem is especially relevant for subscribers living outside large settlements and at a great distance from the nearest cell towers. But even in cities with dense buildings, it may happen that receiving a direct cellular signal is impossible, you have to be content with using a reflected signal that is attenuated several times. In all these cases, it can be quite effective to use additional remote antennas, the proposed designs of which differ in the principle of their construction, complexity and declared radio engineering parameters.

In my case, the problem was the extremely low speed of the Internet connection due to the great distance from the tower (10 km in a straight line). In addition, receiving a direct signal was impossible due to the panel five-story buildings in front. For this reason, the 3G signal was practically not fixed by the modem, and it was possible to work only in GPRS mode (the MTS MF192+ modem was used).

Numerous methods have been considered to increase the level of the received signal, including those found on sites on the Internet. After analyzing the various designs of antennas and feedback on their work, it was possible to conclude that either variants of directional antennas of the "wave channel" type, or reflective dishes, in the focus of which the modem itself is located, work most efficiently. But the manufacture of such antennas requires precise and complex calculations and rather specific materials, so making them at home is not easy. And the options with the removal of the modem itself “outside” (out of the window, onto the roof, etc.) immediately disappeared due to the need to use a USB extension cable with a length of more than 15 m. Even with a much smaller size of such an extension cable, the modem may stop working normally due to attenuation signal and supply voltage drop. In addition, the modem, in principle, is not designed to work outdoors with significant changes in temperature and humidity. Therefore, only indoor directional antennas were considered, the best of which, according to numerous reviews, were the Kharchenko zigzag or bi-square antennas.

But, despite the outward simplicity, there are also many options for manufacturing such an antenna, and quite often completely different sizes of the constituent elements and methods of arranging the entire structure are indicated. To compare all the options in practice, several such antennas with different sizes and in different “modifications” were manufactured and tested in operation, including antenna options with four and six squares (double and triple “bi-square”, respectively). At the same time, my designs made it possible to quickly change the configuration and dimensions of various constituent elements.

It should be said that in my case, the use of double and triple bi-square options showed practically no advantage over the usual, simple version of this antenna. Therefore, in the future, a detailed calculation and features of the manufacture of a "classical" antenna will be considered.

Antenna calculation

To accurately calculate the dimensions of the antenna, neither special theoretical knowledge nor any programs are required.

The perimeter of the loop of this type of antenna must be equal to the wavelength of the received radio signal. In our case, the wavelength can be calculated by knowing the frequency of the 3G signal, which is 2100 MHz. To do this, you need to divide the speed of propagation of radio waves (300,000 km / s) by the frequency, as a result of which the length of the frame is equal to

300,000/2,100,000 = 0.143 m.

Since the frame is square in shape, divide its total length by 4, resulting in the length of each side of the square equal to 35.75 mm. In many sources, you can find completely different side sizes - from 27 to 53 mm. Obviously, such antennas are already designed for a different range, for example, GSM or Wi-Fi, the operating frequencies of which, respectively, are lower or higher than in our case.

The gain of this antenna is approximately 6 dB. In its manufacture, all dimensions must be observed as accurately as possible, the quality of work also depends heavily on the quality of workmanship. It should be noted that any antenna without an amplifier does not amplify the signal as such, but distinguishes it from the background of other signals and various interference (if the antenna is not broadband). Due to this, we get the signal we need, the level of which is much higher than the noise level. Therefore, exact observance of the dimensions of the antenna is important, because in this way we will get an accurate tuning to the desired operating frequency!

To increase the gain up to 9 dB, a reflector can be used. This can be a metal plate, a fine mesh, or even foil glued to plywood or thick cardboard, with dimensions 10-15% larger than the area of ​​\u200b\u200bthe "canvas" of the antenna itself. In this case, the reflector will have dimensions of 125 × 75 mm.

Manufacturing

Thus, the antenna for receiving 3G signals (without a reflector) will look like shown in Figure 1.

For its manufacture, we need a copper wire with a cross section of at least 4 mm 2 (you can use, for example, a “core” from a power electrical cable of the VVG or NUM brand). The perimeter of each square is equal to the wavelength - 143 mm. Since the antenna consists of two squares, you will need a piece of wire 2 × 143 mm = 286 mm long.

We divide the wire into 8 equal segments and bend in these places at an angle of 90 °, and solder the free ends together to form a closed loop (Figures 2 and 3):

The reflector should be fixed behind the "squares" of the antenna, and the distance to the reflector is also of great importance, as it affects the input impedance and matching with the connecting cable. Theoretically, this distance should be ¼ wavelength, which in our case is 143/4 = 35.75 mm. But my antenna, for example, works best at a distance of 18 mm, which is 1/8 of a wavelength. Therefore, it is better to make the distance to the reflector adjustable and experiment with it during the adjustment process. To do this, we take a piece of copper tube of a suitable diameter (our connecting cable should be included there), for example, from a telescopic antenna for receivers / TVs. Give it the shape shown in Figure 4.

We drill a hole in the center of the reflector plate so that this tube fits tightly there. It should not hang freely, then it can not be soldered to the reflector and shifted during tuning, adjusting the distance to the antenna plane. Solder our frame of two squares to this tube as shown in Figure 5).

We pass the cable through the tube and solder its central core to the inner corner of the frame opposite the tube hole, and the braided screen of the cable to the tube on the opposite side of the reflector (Figures 6 and 7).

After the final adjustment of the antenna, the tube can be soldered to the reflector. The plane of the antenna must be strictly parallel to the plane of the reflector, because even a slight misalignment and non-parallelism can greatly reduce the signal level. To ensure the rigidity of the structure between the reflector and the extreme corners of the frame, linings made of textolite or other good insulator can be glued.

Modem connection

If your modem does not have a special connector for connecting an external antenna, then you will have to make a kind of adapter that is put on from the outside and transmits the signal to the modem's built-in antenna by reemission. In the simplest case, you can simply wrap the modem tightly (at the location of its internal antenna) with several turns of the central core of the connecting cable, as shown in Figure 8.

The number of turns, usually equal to 2 ... 5, is selected when tuning to the maximum received signal. Then these turns should be fixed on the modem with electrical tape. And you can make the design more complicated, more convenient and efficient. This adapter option is shown in Figure 9.

Structurally, it is a ring that tightly fits the modem case at the location of its internal antenna. The ring can be made from a strip of copper foil 45 mm wide, the ends of which must be soldered together. The central core of the connecting RF cable is soldered to this ring. From another strip of the same foil, but with dimensions of 25 × 75 mm, a half-ring is bent, as shown in Figure 9, and the braid-shield of the cable is soldered to it. There should be no electrical contact between the ring and the half ring. By adjusting the position of the half ring and the angle of its inclination relative to the modem, you need to achieve the maximum level of the received signal. The dimensions of such an adapter were not theoretically calculated in any way, but were selected through experiments. For modems of different types and models, the location of the built-in antenna inside the case can also be different (near the USB connector or at its other end). This should be taken into account when placing the adapter on the body of your modem!

HF connecting cable

A little about the types and brands of cable. In addition to quality indicators, the cable can have different impedance - 50 or 75 ohms, which must be taken into account when choosing it. Wireless modem impedance is typically 75 ohms. Therefore, it is better, of course, to use a 75-ohm cable. Judging by the numerous recommendations, it is better to use cables of the brands 10D-FB, 8D-FB, 5D-FB (in descending order of quality) due to the low signal attenuation. Cables of the RG-6, RG-8X brands show themselves worse. Therefore, especially with a cable length of more than 5 m, choose a higher quality option, otherwise you can lose all the "gain" that you get from the antenna!

Antenna tuning

After positioning the antenna so that it is directed towards the nearest cell tower (preferably near or opposite a window), adjust the position of the antenna and the distance between it and the reflector plate by moving the tube. You need to navigate by the signal level, and for this it is better to use special programs, for example, the MDMA program (can be downloaded on the Internet), where there is a signal level scale in decibels. This program does not work with all modems, but there are others similar to it, showing the signal level in decibels (the ratio of the “signal to noise” components). You can also navigate in the standard connection program for your modem by the signal level of the antenna icon, but this is not very convenient, because there, firstly, there is a somewhat belated reaction to a signal change (up to 10 - 20 s), and secondly secondly, it will not be entirely correct. Because it is the signal-to-noise ratio that is important, and not the signal level as a whole.

In my case, the antenna scale indicator of the "native" connection manager increased slightly after connecting and tuning the antenna, only 2 - 3 divisions. However, the speed of the Internet connection at the same time rose very noticeably. The download speed increased from 0.5 Mb/s to 3...4 Mb/s during the daytime, and even more at night. Without such an antenna, as mentioned earlier, 3G signal reception was generally impossible.

Many people in the modern world use the mobile Internet - with the help of it, a person can remotely communicate, receive information and even work. But the provider does not always provide users with a stable connection speed due to the characteristics of communication reception, which may be limited by terrain features, a large distance to the transmitter, and other factors.

A homemade antenna for a 3g modem will help you improve the speed and range of signal reception. We offer you some instructions on how to make an antenna for a 3G modem with your own hands.

Kharchenko's method

Recently, we wrote how to make an antenna for receiving television with our own hands. But did you know that you can make a homemade antenna for a 3G modem in the same way?

We will need:

• Copper wire or wire, you need a section of about 30 centimeters;
• 50 or 75 ohm coaxial cable;
• A piece of foil or a DVD as a reflector;
• Tools: knife, soldering iron, pliers, glue, ruler and pencil;
• Plastic bottle cap to separate the antenna from the reflector.

Making a Kharchenko Bisquare

In the photographs of homemade antennas for 3G modems, you can see its approximate appearance. First you need to make markings on the copper wire with a pencil: the length of the outer side of each of the squares should be approximately 35-36 mm.

Gently bend the wire along the markup, helping yourself with pliers. You should get a symmetrical design of two squares touching at the corners. Remove the remaining pieces of wire.

Make a hole in the cover, thread the end of the cable through it. Separate the cable, exposing the inner conductor and the shield for soldering.

Next, solder the antenna to the cable and connect it to the modem. Soldering takes place as follows: solder the central core to the middle of the antenna on one side, and the screen on the other. Then move the cover to the antenna, you can further strengthen and insulate the structure with glue or sealant.

Insert the reflector disc into the wire through the hole, push it to the antenna and glue it to the cover. Solder to the cable on the other side the connector for connecting to the modem. Connect the antenna to the modem. Enjoy the result of your work!

Antenna “double ring”

The next way to create a homemade antenna is more difficult to perform, but gives a greater effect. To complete it, you will need:

• Copper wire or wire;
• Reflector - a flat long tin can, a piece of foil, etc.;
• 75 ohm coaxial cable;
• A short metal tube into which a cable can be threaded;
• Connector for connecting the antenna to the modem;
• Tools: soldering iron, knife, ruler and pencil.

Detailed manufacturing instructions:

• Look on the Internet for a Bi-Loop antenna scheme for a 3g modem - on it you will see a design similar to the Kharchenko antenna, but in the form of two rings;
• Make a marking on the wire with a pencil: for waves with a length of 2050 MHz, the length of each ring should be approximately 146 mm;
• Gently bend a double ring from the wire. It is also possible to make two rings with gaps about 3 mm long and solder their ends to each other, leaving the gaps open;
• Build a reflector. Minimum dimensions: height - 120 mm, width - 170 mm. Any metal panel will do; from improvised means, you can use foil or tin from a tin can;
• Make a hole in the middle of the reflector through which to insert a metal tube - from the connection side with the antenna, the length of the tube should be approximately 18 mm! Solder the tube to the reflector on the other side;
• Separate the cable with a knife: the screen should be soldered, and the conductor should be slightly exposed;
• Thread the cable into the tube and solder the antenna to it: the upper part should be soldered to the conductor, and the lower part to the copper tube;
• Solder the tube and cable sheath;
• Additionally, to amplify the signal, you can use a satellite dish by installing the finished antenna on the bracket;
• The other end of the cable should be connected to the modem connector using a soldering iron;
• Connect antenna to modem. Ready!

Now you know several ways to make an antenna for a 3G modem with your own hands. The above methods should help you solve problems with low Internet connection speed.

Photo antennas for 3g modem

In the modern world, a person cannot imagine life without the Internet, with the help of which one can not only always stay in touch, but also work without leaving home. Due to the imperfection of mobile data transmission technology, frequent failures can occur in the system, so the most convenient way to access the world wide web at any time is to use a 3G modem.

With this device, you can catch Internet signals transmitted over mobile networks, while being anywhere: in the park, in the country or outside the city. The quality of the transmission will depend on the signal strength, so the issue of enhancing the reception of the mobile network using a homemade antenna for the Internet remains relevant.

With the appropriate settings, a homemade 3G antenna or, together with a biquad, can simultaneously act as a receiver and amplifier. The biquadrat is a kind of loop antennas, which are part of the zigzag group. It was invented by the Russian scientist Vladimir Kharchenko. It was first used in the second half of the 20th century to "catch" the signals of television broadcasts. Scientists tuned this device to a frequency of 14 MHz, gave it the necessary position and began to receive signals from the United States of America.

Note! To date, a biquadrate panel antenna for 3G can be bought at a specialized store or you can make such a simple device with your own hands.

According to numerous calculations and experiments by V. Kharchenko, according to the output data, even the work done by digital devices that operate on the basis of mobile platforms. Without a reflector, signal reception increases to 4-5 dB, and with its introduction, the indicator increases to 7-10 dB.

Directional Devices

When there is a signal on the modem, but it is not strong enough, it is recommended to use simple devices to increase the reception power of the mobile Internet. This method is to better position the 3G modem and point its antenna towards the tower. You can use the following available materials for these purposes:

• tin can;
• old saucepan;
• dishes or a simple DVD.

For example, if we consider a can antenna, then here it is only necessary to punch a hole at the base of the can or in its bottom. This is necessary to secure the modem, the correct direction of which will increase the signal.

External antenna

Interesting! The main idea of ​​this method is to create high-quality insulation for the smooth operation of the device in any weather.

You also need to choose the optimal signal direction point. Electrical tape should be used as insulation, which will prevent moisture from entering the microcircuits and wire connections.

A sheet of metal can act as a reflector, which is desirable to be slightly rounded to concentrate the signal at one point. In the absence of a metal sheet, you can take ordinary cardboard, the base of which should be pasted over with foil to reflect signals.

Antenna Kharchenko for 3G

Despite the fact that the device was invented in the middle of the 20th century, its design has not changed at all, as has its popularity. The principle of operation is to capture electromagnetic waves through which the mobile Internet is transmitted.

The advantage of this design lies in the operating range, since there is a multiple reflection of the signal in the atmosphere. Waves go around obstacles, resulting in

Interesting! The Internet can be caught even at a decent distance.

Do-it-yourself antenna for a 3G modem

You can make it yourself with a basic set of tools. For this you will need:

• copper TV cable at least 35 cm long;
• coaxial cable (2-3 m);
• bottle cap, tin or foil;
• scissors to cut the cable;
• any glue.

You also need to prepare a ruler and marker for marking, pliers and a soldering iron to connect the cables to the contacts. If glue is not at hand, you can make it yourself from foam and gasoline (or acetone), combining the components at the bottom of a glass dish.

To do this, you should take into account some subtleties.

Device and optimal dimensions

Interesting! Optimal operation of a 3G modem is possible at a frequency of 2200 MHz, which is equal to a wavelength of 145 mm.

Today in stores you can still see models operating at 900 MHz, but they are no longer so relevant. The key components of the amplifier are represented by a vibrator, an antenna wire, a signal transmission unit and a reflector that eliminates interruptions and extraneous noise.

Basic requirements for a vibrator

The vibrator must be made of aluminum or copper. During the manufacturing process, it is necessary to take into account the fact that the vibrator is small in size, so the cable should be connected by soldering. As for the cross section, it should be 5-7 mm, and the diameter should be at least 2.5-3 mm.

Important! For regular signal reception, the vibrator squares must be symmetrical, and its side surfaces must be of the same size.

Cable selection

The main difference between a 3G antenna and an ordinary one is the size of the wave counteraction, which averages 80 or 55 ohms. To reduce possible power loss, it is recommended to use a wire that has a lower resistance. The advantages of such cables include the best electronic performance, the guarantee of the least signal loss and compatibility with the mechanical dimensions of the vibrator.

The specifics of the design of the reflector

As a screen, you can use any steel plate or cut a tin base from the bottom of an unusable aluminum pan. If there is nothing metal at hand, you need to take a sheet of cardboard or plywood, after wrapping it with foil. Excellent conductivity has a DVD-ROM, one of the sides of which is covered with aluminum foil. Such a device perfectly reflects the waves, greatly facilitating the work, and also having an aesthetic appearance.

Interesting! To make a homemade antenna for the Internet from a disk, you just need to grease it with glue, and then securely glue it on the bottle cap. At the next stage, the distance of the vibrator from the reflector is adjusted, and this is done with additional washers from the screws.

Device creation process

When creating a vibrator, not only dimensions, but also symmetry are of no small importance. To give the installation the most accurate symmetry, all the faces of the squares must be the same, and this result can be achieved using one of two methods:

• pre-mark the wire with a black marker;
• use a pattern or control pattern that has a specific length.

The pliers must be installed on the cable marking, after which the wire should be bent exactly 90 ° to adhere to the bend along the square. Next, the vibrator must be bent using the control drawing for each face of the square and cut the rest of the bent wire using side cutters.

Connection and signal transmission options

In the center of the plastic bottle cap, you need to drill a hole with a drill, the size of which should be slightly larger than the diameter of the cable. Next, one end should be inserted into the hole and disassembled in such a way that the central core with the soldering area is exposed. You can connect the cables using a homemade soldering iron, and then pull the cover onto the vibrator, gradually leading along the wire.

Important! In order to increase reliability in a plastic cork, glue and wiring from small cuts can be used.

A wire must be inserted through the central hole of the disk, and then glued to the end of the cork. Such an efficient installation method does not imply that there will be electrical contact between the vibrator and the reflector.

Sending data wirelessly

Electrodes must be connected to the starting points of the coaxial cable, which will play the role of a generator unit that emits a powerful electric wave. With the help of a thread, you need to make two turns around the modem case (along its outer contour), add 7 mm and cut three strips from metal or foil, the length of which should be 80 mm and the width 45 mm.

The electrodes soldered to the Kharchenko antenna are separated to a certain distance and directed so that the received signal is transmitted to the 3G modem antenna.

Interesting! To check the operation of the finished device, insert it into the computer connector and evaluate the quality of the supplied network.

Is it possible to convert a TV antenna for a 3G modem

Many users today are wondering if it is possible to make a Kharchenko antenna for a 3G modem with their own hands or use a regular TV antenna to feed Internet signals. Even though these two devices include aluminum, it is highly not recommended to use or remake a TV antenna for a 3G modem or cell phone, since they have a different frequency range. As a result, the quality of communication will be much worse and lower.

Thus, the process of making an antenna for the mobile Internet with your own hands is quite feasible. To do this, you just need to study the sequence of actions described above and prepare the necessary materials.

From a modem, buying an antenna on the market is not at all necessary. Making it yourself is pretty easy. However, it should be borne in mind that vibrators differ greatly in shape. If we consider the simplest modifications, then they are made from metal cans. In turn, antennas with a frequency of more than 500 Hz require the installation of a vibrator. To understand this issue in detail, it is necessary to consider some types of models and study their designs.

Can model

Making an antenna for a 3G modem with your own hands from a beer can is quite simple. First of all, an operational-type amplifier is selected to amplify the signal, which can be purchased at any radio engineering store. Directly in the bank for it, you need to make a hole. In this case, a cover is not needed for operation. The cable for this purpose can be used coaxial type. However, for better signal transmission, diffusers with high bandwidth are used. They can also significantly increase the frequency of the device. To install the diffuser to the antenna, you can use a blowtorch. Another antenna for a 3G modem with your own hands from a can can be made with the participation of the regulator.

Antenna with copper winding

It is not very easy to assemble an antenna for a 3G modem with a copper winding at home. For this purpose, the vibrator is selected rectangular in shape. In this case, its side racks must be bent. All this is necessary in order to better capture the signal. Directly the central pin must be installed on the plate. For this purpose, a small hole should be made in it. After that, a blowtorch is used to fix the pin.

The winding in this case should be located on the lower mast. At this stage, the wire needs to be prepared quite a lot. Direct signal transmission must be carried out through a diffuser. It is installed, as a rule, with a beam transistor. It is important to connect the antenna only through an expander. Basically, it is sold in stores with copper contacts. To fix the antenna on a roof or wall, it is important to purchase metal dowels. Also, a support must be welded at the base of the mast.

Device on an aluminum mast

This type of antenna for a 3G modem is made with your own hands (the photo is shown below) quite quickly. If we consider a modification at 400 Hz, then the length of the vibrator should be no more than 40 cm. In this case, the height of the rack depends on the thickness of the plate. On average, it has a size of 50 cm. The vibrator can be installed using a welding machine. However, before this, the side racks must be given the desired shape. For this purpose, you will have to use the machine. After fixing the supports, you can go directly to the diffuser. For this purpose, a beam transistor is prepared first of all. Further, it is important to use an analog converter to connect the antenna. However, it should be understood that the racks must be fixed quite rigidly. In this case, it is necessary to provide for severe weather conditions.

Use of aluminum racks

Do-it-yourself antenna for a 3G modem is made with aluminum racks (the diagram is shown below) using a vibrator. For these purposes, it is more expedient to select a steel type. Next, you will need to install the diffuser itself. In order to change the frequency of the antenna, many experts recommend installing powerful modulators. It is important to mount them at the front pillar. To hide the wires, you should use insulating tape.

In the process of assembling the vibrator, special attention must be paid to the side racks. As a rule, they are installed at a slight angle. All this is necessary for better signal reception. It should also be borne in mind that the bases for the antenna can be made from both steel and aluminum plates. Direct connection of the model can be carried out through digital converters. You can find them in the store for two and three contacts. In this case, it is better to stop at the first option.

Antenna 300 Hz CDMA series

Do-it-yourself CDMA antenna for a 3G modem is assembled at 300 Hz in different ways. In this case, much depends on the shape of the vibrator. If you fold it of a rectangular type without side racks, then the diffuser can be selected with low sensitivity. Direct assembly of the model should begin with the installation of the mast. At the first stage, a metal plate is attached to it. Next, on it you need to make four holes in the corners. For this purpose, you can use a drill. Then it remains only to fix the central pin by welding. In this case, the front of the vibrator should be at a slight angle. It is important to connect the connection conductors directly to the converter. It, in turn, is often installed on the back of the vibrator.

400 Hz model

Do-it-yourself 3G modem antenna folds at 400 Hz using a powerful diffuser. Today, modifications with modulators are in great demand. As a rule, they are sold multi-channel. For their normal operation, you will additionally need to purchase feed-through capacitors. It is important to install them on the vibrator. The plate itself is soldered first. Next, wires are attached to connect to the modem. Only then will it be possible to install a diffuser. At the end of the work, it remains to make a winding and fix the base of the antenna.

500 Hz Antenna Device

An antenna for a 3G modem can be made at 500 Hz in different ways. In this case, much depends on the type of vibrator. You should also consider the parameters of the diffuser. If we consider the simplest model, then it is more expedient to select a vibrator of a rectangular shape. In this case, the diffuser should have low sensitivity. For this, the thickness of the metal should not exceed 1.2 mm. Side stops can be fixed to the antenna using a blowtorch. In this case, the converter is mounted on the rear side of the panel.

For this purpose, you will have to make a hole in it. Only after this is a bypass capacitor installed. All its contacts must be isolated, because otherwise short circuits will occur quite often. It should also be borne in mind that the converter must be fixed rigidly. In some cases, it is installed with an expander. In such a situation, the frequency of the model can be changed using a modulator. However, it is quite difficult to make an antenna of this type on your own.

Feeder modifications

This type of antenna is made for a 3G modem with your own hands using a vibrator. It must be installed only in a rectangular shape. At the same time, the racks for it are made of aluminum. In this case, the feeder is installed on the plate. In this case, the central part should have a length of about 2.4 cm. The side racks in this situation are selected with a small thickness.

Transistors for receiving a signal, as a rule, are used beam type. On average, the frequency of such an antenna fluctuates around 400 Hz. Additionally, it should be borne in mind that only broadband modulators are suitable for the model. In turn, the converters are used in a variety of ways. If we consider a model with a regulator, then it is more expedient to select an analog type modulator. For this purpose, two holes are made on the plate, which will be needed to fix the device. However, before that, it is important to fix the diffuser directly. The next step is to install the conductors for connection.

Devices with a double central conductor

Assembling this type of antenna for a 3G modem with your own hands is quite simple. First of all, it is important to prepare a plate for the model. For this, steel sheets of small thickness are used. It is also necessary to prepare in advance the racks that will be installed on the sides. In this case, they can be quite successfully replaced with conventional iron cans. You can fix them on the panel with screws.

The most common is considered to be modifications with two banks. However, if you need a low-frequency model, then one is enough. Diffusers in this case are selected with a regulator. However, modulators must be installed first. Directly fastening the contacts is on the back of the rack. The minimum length of the vibrator must be 25 cm. In this case, the central core must withstand the load from the capacitor.

Braided vertical polarization model

This type of antenna is made for a 3G modem with your own hands from a mast blank. For this, metal sheets are most often used from aluminum alloy. In addition, for the normal operation of the device, a high-quality diffuser is required. On average, its frequency should be in the region of 300 Hz. However, in this case, much depends on the conductivity of the resistors. It is important to install them on the back panel. For this purpose, an additional plate is attached in a given place.

Before that, the surface is carefully cleaned with sandpaper. Only after that you can proceed directly to the braid. To do this, the wire will need a small diameter. To make the job easier, you can use pliers. The next step is to mount the transducer. They pick it up, as a rule, for two contacts. However, there are many more complex modifications on the market that are quite expensive. In this case, it is more expedient to install a simple model in order to save money.

Vertical polarization device without braid

It is quite easy to assemble an antenna of this type if you prepare a diffuser for it in advance. If we consider a modification at 400 Hz, then it should be selected exclusively cyclic. In this case, the conductivity of the device will depend on the power of the capacitors. In this case, the converters are often mounted through-type. In order to assemble the model, it is first of all important to deal with the vibrator.

For this purpose, metal sheets of small thickness are prepared as standard. Only after that you can proceed to the side pores. For this, only aluminum rods are used. You can bend them yourself using a machine. In turn, the central core is mounted only after the diffuser. Next, you can attach a modulator to the antenna to change the frequency. The next step is to attach the regulator directly. In order to connect the antenna to the modem, you will need to solder the block with contacts.

Bad Wi-Fi is not a reason to change your router or modem. First, try improving your connection with one of our methods.

Almost every one of us faces problems with indoor Wi-Fi coverage: dead zones, insufficient signal strength, interruptions due to background interference from other equipment.

You can buy a new router. You can get by with signal repeaters. You can wire the Internet through ordinary sockets. But the cheapest and fastest way is to make an antenna amplifier. Or completely replace the standard Wi-Fi router antennas.

1. Signal booster from a beer can

The easiest way to improve Wi-FI reception. But the effect is the weakest. We take an empty metal can, rinse from the remnants of the liquid.


After that, it is necessary to cut off the bottom of the can and almost cut off the upper part (remove the key first). After from the side of the cut bottom, you will need to cut the jar lengthwise.


We unfold the jar like a sail, and install it through the drinking hole on the antenna of the router. After that, it is worth fixing an improvised parabolic reflector (like with locators) with tape, chewing gum or glue - with the bottom to the router.


A typical Wi-Fi antenna spreads the signal in all directions. A homemade amplifier directs it to one, thereby strengthening. If it suddenly doesn't work, it's worth making another one by experimenting with the size of the reflector, the length of the sides and the distance to the antenna.

2. External antenna from the disc box

Another option is much more powerful than the previous one. But also more labor intensive. We take a box of discs, saw off the spindle, leaving 18 mm and make an incision in it crosswise.


From copper wire with a cross section of 2.5 mm we make a double rhombus with sides of 30.5 mm. Important - resizing will entail a change in the range of the antenna, and, as a result, poor quality or no connection.


We connect the resulting structure by soldering, and install it in the spindle so that 16 millimeters remain to the base of the box. Strictly parallel to the bottom of the box.


Before that, of course, you need to put 1 disk on the spindle - it will serve as a reflector. However, it can be replaced with foil.


We pass a coaxial cable into the spindle. We solder it to the antenna. At the other end, if desired, you can install a connector suitable for the router (most often an N-connector or BNC-"mother").


We fix the entire structure with a glue gun or other non-conductive material. After that, we install the antenna instead of the standard one.

With the right design, the antenna turns out to be quite good. For an average router, this will be enough for stable coverage on an area of ​​50-70 square meters.

Does it really work?

With such antennas, you can get a good result. Unfortunately, the performance of two antennas made according to the same instructions may differ from each other. In addition, the real parameters of homemade antennas are practically impossible to calculate, so sometimes you have to make several copies of the same design.


Of course, purchased factory-made antennas work much more stable. If there is no time or skill, you should pay attention to these options:

An important advantage of homemade is the cheapness, simplicity and speed of manufacture - 20 minutes, and Wi-Fi works much better. Both for home and for giving, this option can be quite applicable.