Antenna for amateur radio communications. Ideal antenna for amateur radio communications per sq. Antennas for low frequency ranges

I needed a transceiver antenna that would work on all HF and VHF bands and at the same time it did not need to be rebuilt and coordinated. The antenna should not have strict dimensions and should work in any conditions.

Recently, I have an FT-857D at home, this one has (like many others) The transceiver does not have a tuner. They are not allowed on the roof, but I want to work on air, so from the loggia, I lowered a piece of wire at an angle of 50 degrees, the length of which I didn’t even measure, but judging by resonant frequency 5.3 MHz, length approximately 14 meters. At first, I made different matching devices for this piece, everything worked and coordinated as usual, but it was inconvenient to run from the room to the loggia to adjust the antenna to the desired range. And the noise level at 7.0, 3.6 and 1.9 MHz reached 7 points on the S-meter (multi-storey building, near the main street and a lot of wires). Then the idea came to make an antenna that would make less noise and would not need to be adjusted according to bands. Of course, this will reduce the efficiency slightly.

Initially I liked the idea of TTFD, but it was heavy, too noticeable, and a piece of wire was already hanging (don't take it off). In general, taking the principle of this antenna as a basis, I slightly changed its connection, and you can see what came out of it in the picture. An equivalent rated at 100W of power is used as a 50-ohm non-inductive resistor. The counterweight is a piece of wire 5 meters long, which is laid around the perimeter of the loggia. I think that several resonant counterweights will improve the transmission performance of this antenna (just like any other pin). The RK-50-11 cable goes to the radio station and is about seven meters long.

When this antenna is connected to a radio station, the air noise is reduced by 3 - 5 divisions on the S-meter, compared to the resonant one. Useful signals also drop slightly in level, but you can hear them better. For transmission, the antenna has an SWR of 1:1 in the range of 1.5 - 450 MHz, so now I use it to work on all HF/VHF bands with a power of 100 W. and everyone I hear answers me.

To make sure that the antenna works, I conducted several experiments. To begin with I made two separate connections to the beam. The first is a shortening capacitance, with it we get an extended pin at 7 MHz, which matches perfectly and has an SWR = 1.0. The second is the broadband version described here with a resistor. This gave me the opportunity to quickly switch matching devices. Then I selected weak stations on 7 MHz, usually DL, IW, ON... and listened to them, periodically changing matching devices. Reception was approximately the same on both antennas, but in the broadband version, the noise level was significantly lower, which subjectively improved the audibility of weak signals.

A comparison between an extended rod and a wideband antenna, transmitting in the 7 MHz range, gave the following results:
....communication with RW4CN: for extended GP 59+5, for broadband 58-59 (distance 1000km)
....communication with RA6FC: for extended GP 59+10, for broadband 59 (distance 3km)

As you would expect, the broadband antenna loses on resonant transmission. However, the magnitude of the loss is small, and with increasing frequency it will be even smaller and in many cases it can be neglected. But the antenna really works completely and very wide range frequency

Due to the fact that the length of the radiating element is 14 meters, the antenna is really effective only up to 7 MHz; in the 3.6 MHz range, many stations hear me poorly or do not respond at all; at 1.9 MHz only local QSOs are possible. At the same time, from 7 MHz and above there are no problems with communication. The audibility is excellent, everyone responds, including DX, expeditions and all sorts of mobile radio stations. On VHF I open all local repeaters and conduct FM QSO, although on 430 MHz the horizontal polarization of the antenna greatly affects it.

This antenna can be used as a main, backup, receiving, emergency and anti-noise antenna to better hear remote stations in the city. By placing it like a pin or making a dipole, the results will be even better. You can “turn” into a broadband any antenna already installed earlier (dipole or pin) and experiment with it, you just need to add a load resistor. Please note that the length of the dipole arm or the length of the pin blade does not matter, since the antenna has no resonances. Length of the canvas, in in this case only affects efficiency. Attempts to calculate the antenna characteristics in MMANA failed. Apparently, the program cannot correctly calculate this type of antennas; this is indirectly confirmed by the TTFD calculation file, the results of which are very doubtful.

I haven't checked yet, but I'm guessing (similar to TTFD) that to increase the efficiency of the antenna, you need to add several resonant counterweights, increase the beam length to 20 - 40 meters or more (if you are interested in the 1.9 and 3.6 MHz bands).

Option with transformer
Having worked on all HF-VHF bands using the option described above, I slightly redesigned the design by adding a 1:9 transformer and a 450-ohm load resistor. Theoretically, the efficiency of the antenna should increase. Changes in design and connections, you see in the figure. When measuring the uniformity of overlap using the MFJ device, a blockage was visible at frequencies of 15 MHz and higher (this is due to the unsuccessful brand of ferrite ring), with a real antenna this blockage remained, but the SWR was within normal limits. From 1.8 to 14 MHz SWR 1.0, from 14 to 28 MHz it gradually increased to 2.0. On VHF bands, this option does not work due to the high SWR.

Testing the antenna on the air gave the following results: The air noise when switching from an extended GP to a broadband antenna decreased from 6-8 points to 5-7 points. When working with a transmission power of 60W, in the 7MHz range, the following reports were received:
RA3RJL, 59+ wideband, 59+ remote GP
UA3DCT, 56 wideband, 59 remote GP
RK4HQ, 55-57 broadband, 58-59 remote GP
RN4HDN, 55 broadband, 57 remote GP

On page F6BQU, at the very bottom, a similar antenna with a load resistor is described. Article in French. So the goal has been achieved, I made an antenna that works on all HF and VHF bands and does not require coordination. Now you can work on the air and listen to it while lying on the couch, and switch bands only with a button on the radio station. Laziness rules the world. hee. Send your feedback......

Option number three
I tried another option, broadband antenna matching. This is a classic 1:9 unbalanced transformer loaded with a 450 ohm resistor on one side and a 50 ohm cable on the other. The length of the beam is not particularly important, but unlike the previous design, it is important that it does not resonate on any amateur band (for example 23 or 12 meters). then the SWR will be good everywhere. The transformer is wound on a ferrite ring with three wires folded together; I got 5 turns, which need to be evenly spaced around the circumference of the ring.
The load resistor can be made composite, for example, 15 pieces of 6k8 resistors of the MLT-2 type will provide you with the ability to work in CW and SSB with a power of up to 100W. As grounding, you can use a beam of any length, water pipes, a stake driven into the ground, etc. The finished structure is placed in a box from which comes a PL connector for the cable and two terminals for the beam and grounding. Operating frequency range 1.6 - 31 MHz.

HF Antennas. Shortwave antennas on amateur bands, is and remains one of the hot topics in amateur radio. The beginner looks at which antenna to use, and the broadcast aces from time to time look at what’s new. In order not to stand still, but to improve our results, we are following this path of understanding and improving our antennas. It is even possible to single out some radio amateurs as separate group- Antenna operators.

IN Lately antennas and ready-made ones have become more accessible. But even having purchased such an antenna along with the installation, the owner, in our case the radio amateur, should have an idea. In my opinion, everything starts with the place where our antennas will be placed, then the antennas themselves. Of course, not everyone is given the choice of place, but here we can win big, and how to choose, not everyone is given such an instinct, but there are such radio amateurs.

HF Antennas come first

Technically, comparing a location on HF is problematic (on VHF it’s easy and measurements show a difference of four decibels). Let those who have to choose such a place be lucky. For the HF bands we have a larger selection of antennas and the dimensions are tolerable, but for the LF bands the choice of ready-made antennas is smaller. And it’s understandable - five yaga elements for the 80-meter range are not affordable for everyone. This is where the field of work can be large, if a radio amateur has such a field for placing antennas in the low frequency ranges

There is a book with a lot of information on antennas for low frequency bands

Amateur antennas of short and ultrashort waves

The antenna is a device involved in the transmission process electromagnetic energy from the power line to the free space, and vice versa. Each antenna has an active element, such as a vibrator, and may also contain one or more passive elements. Active element antennas - - vibrator, as a rule. directly connected to the power line. The appearance of alternating voltage on the vibrator is associated both with the propagation of the wave in the power line and with the occurrence electromagnetic field around the vibrator.

Ideal antenna for amateur radio communications on HF

What antennas do we, radio amateurs, use? Which ones do we need? Do we need an ideal antenna for meter bands. Say that there are no such people, and that nothing is perfect at all. Then close to ideal. What for? You ask. Anyone who wants to achieve results and move forward will sooner or later come to this question. Let's look at how to understand an ideal antenna on the meter amateur bands. Why on amateur meter, and because our correspondents are on different distances V different sides Sveta. Let's add here the local conditions where the antenna is located, and the conditions for the passage of radio waves in given time at these frequencies. There will be a lot of unknowns. What angle of radiation, what polarization will be maximum in a specific period of time with a specific correspondent (territory).

Yes, some may get lucky. With location, choice of antennas, height of suspension. So what should you do? To always be lucky. We need an antenna that at any given time will have the best parameters for a given passage of radio waves with any territory. More details = We scan (rotate) the antenna in azimuth, this is good. This is the first condition. Second condition = we need to scan along the radiation angle in the vertical plane. If anyone doesn’t know, depending on the transmission conditions, the signal can arrive at different angles from the same correspondent. The third condition = is polarization. Scanning or changing polarization from horizontal to vertical polarization and back, smoothly or stepwise. By creating and obtaining these three conditions in one antenna, we get ideal antenna for amateur radio communications on short waves.

Ideal antenna

Ideal antenna, so what is it. If we consider, for example satellite dishes, then perhaps it becomes clearer and easier to understand. Here we take the size (diameter of the plate), this is a direct dependence on the gain. One satellite – we took a 60cm antenna as an example. diameter The signal level at the receiver input will be low, and sometimes we will not see the picture. Let's take an antenna with a diameter of 130 cm. The level is normal, the picture is stable. Now let's take an antenna with a diameter of 4 meters and what can we observe. Sometimes the picture disappears. Yes, there could be two reasons. It was the wind that shook our 4-meter antenna and the signal disappeared. This satellite in orbit does not maintain its coordinates stably. So, on the one hand, it turns out that the 4-meter antenna is the best in terms of gain, but on the other hand, it is not optimal, which means it is not ideal. In this case optimal antenna 130 cm. In this case, why can’t we call it ideal.

Same for meter ones amateur radio bands. Five yagi elements at a height of 40 meters for the 80-meter range will not always be optimal. So, not ideal. You can even give some examples from practice. In my laboratory work I made 3 elements for the 10-meter range. Passive elements are curved inward of the active one. Then a three-band version of such an antenna will come into fashion under the well-known name. I listened, twirled it, and of course made connections to this antenna, the first impression was wonderful. Then the weekend came, another contest. But when I turned on 10 with this antenna, there was silence, so I think, yesterday the range thundered, but today there is no passage.

From time to time I turned on this range to listen in case a passage suddenly began. During the next approach to 10, numerous amateur radio stations deafened me - it began. And then I immediately discover that the wrong antenna is connected. Instead of 3-elements there was a pyramid for the 80-meter range. I switch to 3 elements - silence, signals are blaring on the pyramid. I went outside, examined 3 elements, maybe something happened, no, everything is fine. Well, then I worked on 28 megahertz, made a lot of connections to the pyramid for the 80-meter range. On Monday and Tuesday the same picture was observed, and only on Wednesday things seemed to fall into place. There is silence on the pyramid, but on the 3-element there is noise. What is the difference? Difference in radiation angle.

In my pyramid the radiation is at 28 MHz. at an angle of 90 degrees, that is, at the zenith, and in a 3-element one below 20 degrees. Such practical example gives us something to think about. Another example was when I was in the zero area. I hear a call on the 20 for the zero region, I know that this friend has an antenna for several thousand dollars, that it is at a good height and the power amplifier there is no less than a kilowatt. I call him, but he doesn’t hear, or rather, he hears, but he can’t even make out the call sign. He twisted his expensive antenna, to no avail, and he said out loud that there was no way through today. Here on this frequency I hear - and you receive me. Yes, I accept. It turned out that his neighbor had only five watts and the antenna was such that I had already forgotten (perhaps like a triangle at 80). We made radio contact, and he was pleasantly surprised, knowing what antenna and power his neighbor had. I don’t know how many meters or kilometers there are between them, but in that case the cool antenna was powerless.

Antennas for low frequency ranges

There were such laboratory works both on the 40 and 80 meter bands. All this is in search of which antenna is better. And there is a point where radio amateurs still have the opportunity to work on such an antenna so that it is optimal at any time, and therefore ideal. In part, radio amateurs use some points that should be included in an ideal antenna. The simplest thing is to set it in azimuth. The second in terms of radiation angle is to place identical antennas on different masts, at different heights or on the same one, while switching them into stacks. We get different radiation angles. And also different antennas with different polarization, some have. But this is partly, not overall. And some will say, why such an antenna? Ten kilowatts and first place in your pocket. Yes, it's your choice. At the same time, you are deceiving not only everyone, but first of all yourself. Or who has been using such an antenna for a long time on HF (there is one on VHF), where the properties of an ideal antenna are inherent.

Our antennas

kv antennas

For many radio amateurs, this topic was, is and will be one of the most popular. Which antenna to choose, which one to buy. In both cases, we need to mount it, install it, configure it, here we need some knowledge on antenna topics, magazines and books on antenna topics will help here. So that, in the end, we understand something. That the antenna of a radio amateur should be one of the first lines. That SWR is not an indicator and there is no need to chase after it in the first place. That an antenna with SWR=2 can work much better than with SWR=1. That efficiency decreases with increasing elements and much more.

kv antennas

Log-periodic wire antenna for the 40 meter range. Everything is simple and effective. Several variants of “sloper” antennas for low-frequency bands of 40,80,160 meters. Scanning antenna RA6AA, setup, parts used. In the magazine Radio Amateur 1 1991. Read in full.

Practice tuning and installing antennas. Raising the mast. Options for attaching antenna panels to wood. Tuning using GSS and a tube voltmeter in the magazine Radio Amateur 2 1991. Read.

In the seventh issue for 91 years of Radio Amateur magazine RA6AEG talks about its M antenna.

All this information is primarily for those who already have the call sign of an amateur radio station. Also for everyone else who has not yet come to HF.

Name: Amateur antennas of short and ultrashort waves.

A wide range of issues are considered (the theory of antennas, power lines, radio wave propagation, etc.), the study of which will help to purposefully select antenna circuits and its parameters for various methods of amateur radio communications. Descriptions of the main types are made amateur antennas, including their numerous modifications and recommendations for manufacturing and configuration.
For a wide range of radio amateurs.

In addition to purely antenna topics, the book examines the theory of long lines, which helps to understand the theory of wire antennas and power lines, and outlines the issues of designing baluns and matching devices (without which it is difficult to obtain good internal parameters antennas), provides basic information about the propagation of radio waves (without knowledge of which it is impossible to make the right choice external parameters antennas).
The radio amateur is already familiar with a number of publications on the theory and technology of antennas (let us note in passing that they are clearly not enough) and has the right to wonder what new this book will give him. It seems to us that we have already partially answered this question. Let us add that in terms of the variety of problems considered related to the design of amateur radio antennas, in terms of the number of antennas analyzed and the extremely large volume of calculated and experimental data, this book surpasses other well-known publications.

Translation Editor's Preface
Chapter 1. Introduction
1.1. Amateur radio antenna devices
1.2. Classification of amateur radio antennas
Chapter 2. Elements of antenna theory
2.1. Electromagnetic field
2.2. Power lines
2.3. Elements of Antenna Theory
Chapter 3. Antenna Power
3.1. Options for building power lines
3.2. Practical implementations matching systems
3.3. Balancing devices
3.4. Coordination of the “transmitter-power line” system
Chapter 4. Propagation of Radio Waves
4.1. Introductory Notes
4.2. Methods of propagation of radio waves
4.3. Basic patterns of radio wave propagation
4.4. Energy balance of radio communication lines
Chapter 5. Shortwave Antennas
5.1. Introduction
5.2. Harmonic antennas
5.3. Aperiodic aitenns
5.4. Dipole antenna systems
5.6. Wave channel dipole antennas
5.6. Loop antennas
5.7. Loop antennas
5.8. Vertical dipoles
5.9. Antenna DDRR
Chapter 6. Ultrashortwave antennas
6.1. Introduction
6.2. VHF dipole antennas
6.3. Antennas surface wave
6.4. Antenna arrays
6.5. Antennas for satellite communications
6.6. Reflector antennas
6.7. Spiral aithennas
6.8. Recommendations for radio amateurs
Applications
Bibliography

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For many years, amateur radio has remained an important means of communication, thanks to in various ways transmitting messages from one place to another. Most types of antennas were invented out of necessity. During the Titanic tragedy, discharge transmitters were used. In those days, such transmitters were called wireless, a name that is still used today. Antennas send signals through the air. Since the days of bit transmitters, amateur radio has gradually changed under the influence of progress. Thanks to the power, high-voltage coils became widespread, with the help of which the “dots” and “dashes” of Morse code were sent. The recipient or recipients on the other end, familiar with Morse code, wrote down the symbols and put them into words. An amazing way of communication, quite primitive if you look at it from the point of view modern technologies, nevertheless, at that time it was the most popular way of transmitting information.

Steps

It's all about the antenna! At the heart of amateur radio is the antenna design. Some ignorant people may argue that the main thing is power, but this is not true! The antenna is the heart of any radio installation, be it amateur radio or a commercial, business, civilian or private family transmitter, including experimental low-power amateur devices. Without a good receiver, you will not hear anything; without a good antenna, you will not be able to transmit information to long distances, even if you use radio frequencies high performance or high voltage in the electrical network!

If you're planning to build an antenna, your thoughts may wander in different directions. In order not to get confused, you need to decide on the following factors. Decide what the height and length of the antenna will be, the electrical supply wiring, the balun (we will touch on the balun later in this article), insulators, the type of wires used and the choice of wire material, the purpose of the antenna, what bands you intend to work in, whether suitable materials are available, yes Is there a place to install the antenna? And most importantly, if you live in an area with zoning laws, you will need a permit to install an antenna on your own home!

Use materials that are easy to combine. The antenna can be made from different materials. Remember that you will need metals that are similar in quality, since dissimilar metals are susceptible to corrosion or have non-conductive properties. Metals such as copper, aluminum, tin or steel are excellent conductors of electricity. However, when we're talking about about radio frequencies, surface electrical conductivity is sufficient.

The aluminum wire for the antenna is very inconvenient to use, because... it bends too easily, does not hold its shape, breaks and cannot be soldered if necessary. Aluminum wire is inexpensive, but should be used last when making an antenna. Prices for copper electrical wiring have increased significantly recently. Try to find old used pieces copper wire. The thickness of the 12 gauge wire is only 3 mm. This wire is easy to work with. Perhaps this is the most suitable metal for an antenna.

Tin wire, which is used to make electric fences, makes an excellent antenna. In addition, this material is inexpensive. The only thing is that it is only sold in whole reels. If you are planning to build multiple antennas, then it will not be a problem for you to use up the entire coil.

# How it works. Variable and D.C. pass through the middle of the wire while radio frequencies travel across its surface. Imagine cutting a wire. If electricity running through a wire could be seen, then the direct and alternating current would be right in the center. At the same time, radio frequencies would spread to the outer surface of the wire. Each metal from which the wire is made has its own conductivity scale. Few people would think of using precious metals to produce antennas. However, rare metals such as gold, silver and platinum are the most conductive materials, but due to their high cost, it is more profitable to use copper or steel wire with brass or copper coating, or tin wire with or without copper coating, or regular tin wire for electric fencing, or, at worst, aluminum wire. Any conductor of electricity will also conduct radio frequencies. The worst option would be to use mechanical wire, which has high resistance and is also easily susceptible to corrosion and rust, which can lead to unnecessary resistance growth and antenna failure. Under the influence weather conditions, mechanical wire quickly rusts, which leads to endless breakdowns or, even worse, to a complete lack of conductivity. The wire stops emitting radio frequency energy and stopping receiving signals sent to you by other amateur stations. The optimal solution, from the point of view of price and quality, would be to use the wire used for the construction of electric fences, with a sheath of copper or brass (do not forget that radio frequencies are transmitted only on the surface). It is better to avoid using steel because steel rusts easily, even with a brass or copper shell. You can use unsheathed tin wire, which is used to build electric fences. In this case, you will have to check the connections from time to time, clean them of corrosion and solder them if necessary. A wonderful antenna can be made from insulated house wiring. At least 70% of all amateur antennas are made from various types insulated and non-insulated wire. They will be discussed in this article.

Start by choosing a location and space to install the antenna. Never install an antenna near a power cord - contact with such a cord can cause serious injury or even death. A single touch is enough power cable under voltage, and an attempt to install the antenna may end in the most tragic way. Determine the position of the high-voltage wires and position the antenna so that the distance from it to the nearest wires is at least one and a half times the length of the longest stand. It is best to place the antenna close to your radio room. The easiest antenna to maintain is one located in the backyard, close to your radio room or shed. Avoid where electrical wires enter the house. Use straight wire, no knots or twists. If you are using copper or brass plated tin, pay attention to its ability to curl. Sometimes tightly wound wires, regardless of the material or coating, are also twisted back. Some wires, especially steel, have very sharp cuts, also caused by using sharp pliers when working with some metals. The thinner the wire, the more difficult it is to work with. Thus, the use of wires of gauge from 17, 18 to 22 and 24 is associated with many problems, in particular the fragility of the design. For most antennas, we recommend using at least 18 gauge wire. As stated, not all locations can accommodate an antenna. A good option would be to place the antenna in the attic, if attic space allows. Such antennas work great, unless the roof of your house is made of metal.

Choose the material for the wire. The wire must be in working condition and withstand various weather conditions, both summer and winter. In other words, don't use a wire that can cause a lot of problems after you connect your device. An insulated copper wire would be ideal, but do not remove the insulation under any circumstances! In fact, insulation can significantly extend the life of the antenna. In addition, insulation also protects against short circuit in contact with a tree, as well as its leaves, seeds and branches. Exposed wires should be kept away from the ground (we'll talk about this later) to prevent other people from accidentally touching them, especially if they are RF-energized. Radio frequencies are the invisible energy of the directed movement of electrons in an alternating electrical flow. RF voltage can cause painful burns to the fingers and hands.

Many modern circuits settings at the slightest touch can cause burns, and very serious ones that penetrate into the deep layers of the skin. Such burns are called “radio frequency bites” because they feel very similar to an insect or bee sting that does not have poison, but the bite site is very hot. Amplified radio frequencies can also cause serious injury. If you are using a tube amplifier, depending on the power it is set to, the amplifier can also cause serious injury.

Use only verified and tested schemes. The easiest way is to install the antenna on a dipole, and then raise the middle part and give it the shape of an inverted tick. Right size antenna will be half its wavelength, while optimal distance from the ground will be equal to 1/4 wave. IN emergency you can quickly make a J-antenna for VHF. For this, a common voltage of 300 Ohms is used. Such antennas can be used to operate in different bands, even high frequencies, but for this you will need a high support or tree to raise the antenna as high as possible.

At the time of writing this article, 300 ohm wired antennas are extremely rare. Just a year ago, a coil of antenna wire of 300 or 450 Ohms cost $55 (about 2000 rubles), and now, if you manage to find it, the price will already be $95 (about 3400 rubles)
1. Check your VHF and UHF bands. Some people blame amateur radio for their own stupid mistakes. There are frequencies that can interfere with the operation of toys such as radio-controlled cars, airplanes and robots. It's not the radio amateur's fault. In fact, the problem may be due to flaws in the design or protection of the toys. In addition, such toys can act as a receiver, and they can blame you. A similar incident occurred recently, and we will look at its consequences later. Now let's get back to talking about the construction of antennas.
  
  Maximum power! What is maximum power? Peak power Peak Envelope Power (PEP) is the maximum power value allowed by law averaged over one radio frequency period from the source alternating current, radio frequency power. Taking into account recent changes in legislation, local authorities authorities may also limit the amount of energy consumed. By law, radio amateurs can use up to 1500 watts. This is a lot, but you need to understand that a station that costs 10 thousand dollars will not really work if you equip it with an antenna that costs 50 cents. Regardless of whether you live in a city or a village, the quality of the signal sent and received depends on the quality of the antenna.
  
  Seven times measure cut once! To determine the length itself popular model antenna - dipole, use mathematical formula 468/FMHz, where 468 is a constant value and FMHz is the required frequency in megahertz. The result will give you the length of the dipole antenna in feet. Divide in half and place ceramic, bone or PVC tubing insulator between the ends of the antenna and you have a dipole antenna. Connect the electricity and you can run to the settings regulator. In case you need a resonant antenna, connect it to the coefficient meter standing wave(SWR) and watch for a clean signal to appear. Usually, a result of 1:5 is considered good, and 1:1 is considered the best. The use of resonant antennas is considered perhaps the most exciting in amateur radio, although due to limited space and materials, it is worth thinking about the advisability of using several resonant antennas for different bands.
  
  Changing the height of the antenna will help catch the desired wave, but do not forget about the need to install the antenna at a height of at least 1/4 of the wavelength. Antennas in the shape of an inverted letter V can be placed as high above the ground as desired, but not lower than 90-120 cm from the surface. Post a warning sign if your antenna hangs low enough to touch. The sign must contain information about high voltage and a ban on any touching.
  
  Spread the antenna antennae as wide as possible, while extending them as high as possible. The larger the coverage area, the better signal. To secure, use a strong nylon or viscose cord about 1 cm wide. This is a very reliable method of fastening, but do not forget to inspect it every six months for abrasion and wear due to weather conditions. Replace if necessary.
  
  Create your own scheme! Over the years, many radio amateurs have enthusiastically come up with more and more new models of radio stations. The latest development is the cellular dipole. To make it, you will need a PVC manifold or drain pipe 10-15 cm long and a tool to cut it into distributor rings about 1 cm thick. A miter saw or a regular saw up to 30 cm works great. Be careful when cutting the last 30 cm of the pipe, since this piece can bounce off and hit you. Only saw in safe sections. Usually there are about 30-35 pipes left. If you or your friends have a saw, use it. Once you have cut enough spreaders, measure them along the outer radius in cm and mm. Depending on the expected number of wires, divide the resulting circumference by 6 or 8. Once you have decided on the diagram, use a drill with a drill bit with a diameter of 0.3 cm to 0.4 cm, depending on the diameter of the wire you are going to use . Be extremely careful.
  
  The above formula is not suitable for a cell dipole - such a dipole will be shorter than normal, and its size is determined depending on the size of the distributor. The usual formula can be used as a starting point. Depending on the distributor size, you may have to reduce the length by 4% or more. What matters is how many lead wires you use - 6 or 8. These types of antennas typically use electric fence wire and can be purchased in large quantities - up to half a mile per roll. Tin wire will also work in a project like this. However, copper will best choice. Choosing a material other than copper will be a compromise.
  
  Conduct precise measurements, even if at this stage it is not critical. It's always better to cut a little longer than a little short and then add wires. When you have finished measuring and cutting the wires, fold them in the center. It is better to start working on this project with friends.
  
  Now let's play - assembling the antenna! Take 5 distributors, 4 of which put on the wires and distribute along the entire length at a distance of 45-50 cm from each other. To fix it on the wire, place cement on the tip of a toothpick (or match) into the holes. Leave the fifth distributor at the very beginning, so that you can see the points where the wires enter the holes on the distributors. Continue with the next batch of 4-5 spreaders, leaving one at the beginning. Stretch the wires and secure them with toothpicks or matches, using only the wooden part of the matches. When you get to the end of the wires, gather up all the loose ends on both sides and tie them together using a piece of wire, winding all the ends in the center of the distributor ring. Set aside the finished part of the antenna and assemble a second one, the same.
  
  Be careful and consistent. Regardless of the chosen distance between the distributors (45 cm or 50 cm), make sure that it is always the same. This will add aesthetics to the future antenna. Do not change this distance. If you decide to place the distributors at 45 cm distances, then the distance between all distributors should be exactly 45 cm. Thicker wires of sizes 14 or 12 may be too heavy, and it may be difficult to get such an antenna up to working condition. Take your time! Take your time, work efficiently so that you don’t have to redo it. In this case, you will be sure that the antenna will perform its functions. The coverage area of a 6-wire cell dipole will increase by 5 times, and if you use 8 wires, the coverage will increase by 7 times! Of course, building such an antenna is a labor-intensive task, but it is one of the best options antennas for amateur radio stations.
  
  Blip, blip, and you're done! The loop antenna is ham radio's best-kept secret. Resonant antennas are made for a specific medium wave band, and are used in conjunction with a tuning control powerful enough to pick up several bands. The formula for calculating the length of a loop antenna is 1005/FMHz. This is the length of the frame depending on the wavelength you are going to catch. To assemble a loop antenna, fold the wire into a triangle, square or rectangle shape and your loop antenna is ready. Such antennas are most popular in rural areas– its installation requires a lot of free space. The antenna can be powered either from the end of the wire or from the middle. When you lift this little monster vertically into the air, be careful not to hit any power lines! Separate trees can serve as a sufficiently high support for such an antenna. Such trees are sometimes called "poor man's towers." To reach the top of the tree, various tools are used, including fishing rods or sinkers weighing 100 g, which are thrown onto the upper branches of the tree. If the grab is successful, secure the rope and carefully pull the top of the tree towards the ground. Don't forget to use a safety cord, or use a rope of sufficient length. A PVC pipe is suitable as an insulator. Cut 3-4 pieces of PVC pipe, about 4 cm thick and about 15 cm long. Drill 1 cm holes, but never drill close to the cut. It is considered sufficient to retreat 5 cm from the end of the segment. To supply electricity, use another piece of PVC pipe, in which you need to drill a through hole to relieve the tension on the supply wires. Very carefully lift the antenna onto a tree or tower, making sure that its shape matches the intended design as closely as possible. Regardless of the shape (triangle, square or rectangle), the edges of the antenna should be as far apart as possible. Yes, you can be careless in manufacturing by making one edge a little longer, but it’s better to strictly follow the pattern.
- Carefully strip the wire, connect the ground parts together and solder them to the negative pole of the antenna wire. All three wires must be soldered and neatly connected;
- Seven times measure cut once. Although not as important when making a cage dipole, for other types of antennas it is necessary to accurately measure the length of the antenna, depending on the range in which you intend to work;
- Enlist the help of friends. Your friends might really enjoy building antennas.
- Use similar wires. Avoid using wires that are easily corroded, brittle, or have low conductivity;
- Locate the antenna as close to your radio room as possible to avoid unnecessary loss of RF energy;
- Hearing the whole world through a wire is very exciting. Antennas are the heart of any radio station;
- Cutting wires with blunt tools can leave sharp ends that can easily cause injury. Avoid sharp ends during the construction process;
- Stay away from power lines;
- Use inexpensive and easy-to-use PVC pipe to make insulators and distributors.
What you will need
- Antenna wire from those listed above. Always take extra;
- A good soldering iron and rosin;
- Knife, pliers, wire cutters, drill and drill bits;
- PVC pipes of any diameter for use in the manufacture of antennas and insulators;
- Do not place the antenna near power lines.
Sources
- Consult any ARRL handbook for FAQs about antennas. Other pertinate information and articles from using diodes and resistors to control current, and useable information about antennas are listed there. Consult any ham radio operator about H.F. antenna construction.

Install the antenna – The best way increase signal strength. HF antennas work very well at low altitudes and distances from other objects. The resistance depends on the height of the suspension. Short wavelengths are very often used vertical devices. As a rule, they do not require large space. This influenced the fact that radio amateurs began to actively use them and tune shortwave signals. One of the few that makes it possible to have a good time in front of the transceiver and not carry out permanent setting reception. You can measure the incoming signal using an SDR device. It consists of a receiver that converts long-range radio frequencies and transmits them to the radio.

HF antennas

Many people take receivers with them to work or leisure. Most often, a piece of wire serves as an assistant in tuning radio stations. As practice has shown, it is enough to make a signal long range clearer by a few points. HF antennas for radio amateurs have become increasingly in demand. This is due to the development of technological processes. Recently, such devices have become available. Buying an HF antenna for the amateur bands is now not difficult. On our website you can find any product you are interested in.

Wideband HF antenna

This unit is a vibrator with a loop with different blade lengths and distances between wires. Main advantages:

Can operate without the use of separate power.
High power makes them very popular among a wide range of consumers.
Independence from weather conditions.
Can be used as part of base radio stations to enhance power.

During an emergency, the HF antenna has the ability to use communications with other stations to transmit information. It is ready for transmission on any frequency. This does not require the use of additional settings. HF antennas are active means of receiving and transmitting information.
You can buy such devices at a low price in our online store. average cost not tall. You can view the price list in more detail on the Internet portal. On the RadioExpert website you can order delivery. Sales are made in all regions of Russia and CIS countries.