Antennas and their setup. Antennas and their setup How to lower the resonant frequency of the antenna F23

Diamond F23 is an omnidirectional antenna for stationary stations of VHF radio systems. Used by radio amateurs as an antenna of base stations, as well as departmental organizations in constructing systems of land moving radio communications.

Setting base antenna Diamond F23. It is carried out with a trimming of antenna canvas according to the attached instruction. This is not always easy, since the pin and each of the elements are protected by a fiberglass case, which provides high resistance to wind loads. As an alternative to self-modifying design, we propose to contact the specialists to configure the antenna equipment that will cope with this task competently and in a short time.

Measuring the characteristics of the Diamond Diamond F23 base antenna is performed using special devices - KSW meters, which allow you to analyze the nature of the propagation of radio waves in a coaxial cable or another waveguide.

Characteristics:

• Dimensions, M: 4.6
• Range of operating frequencies, MHz: 144
• Case material: Fibergles
• Antenna type: vertical omnidirectional
• Gain ratio, DBI: 7.8
• Maximum supplied power, W: 200
• Impedance, Ohm: 50
• Connector: SO-259
• Weight, kg: 1.7
• Fastening method: on a pipe with a diameter of 30 to 62 mm

Characteristics

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To collect this antenna you need 4.5m aluminum wire diameter 2.5mm, copper wire with a diameter of 1.2mm, 1.5mm and 4m plastic pipe with a diameter of 25mm.

Dimensions are shown in the figure. The coils are made and fastened on flat textolite frames along the edges of the foil left and coils are rummbled to them. The matching coil is soldered to the connecting housing. The textolite plate of one side is soldered to the central output of the selection, to the opposite side, the other output of the coil is soldered. Capacitor with a capacity of 5.6pf is inside the coil.

In the photograph of the coils that I use. The elements of the antenna are attached with the help of electrical terminals that can be purchased in the store. Brassal terminals must be soldered to the sites to which coils are already soldered.

All items starting from the top are assembled and fastened with screws, after that the entire antenna is carefully inserted into the plastic tube. To get rid of the effect of rattles, you can use a paralysis, or pieces of fiberglass equal to the inner diameter of the plastic pipe.

Mounting to the mast is carried out using a glass of 50mm with a height of 25mm (for my case). At a distance of 20mm, from the top edge of the glass, three holes for counterweights with a diameter of 5mm are drilled. The length of the counterweight is 51cm. Two washers in the figure are for the option of the collapsible hiking antenna (2 to 2m).

I express deep gratitude to Oleg RW4PJD for the opportunity to remove the size from its antenna. Questions Please send to the address

Victor Oleinik (UA4PJT), This adress email Protected from spam bots. You must have JavaScript enabled to view.

Final F-23:

Small adjustment for setting up!
Today I set up one such an antenna! Super! Here is a description.
1. The system is adjusted to the resonance on the average frequency of 144.8MHz-146.MHz.
2. Lower circuit L1- set to 145 MHz. So showed MFJ-269. The only advice Sare for a permanent condenser in 3pf Parryrallelly small-suspension from 2-25 PF.one will help you in further configuration of the input circuit!
3. Incarnate the 1st wire with a margin and set it up for its length in the rosonance at 146 MHz (without resonant coils) !!! If the resonance passed, then we bite or do the length of the wire. Similar and second - (upper piece of wire)!
4. We will configure the average wire into the resonance by 145 MHz.
5.Some, each of the l2-l3-l3 slices pay fees with resonant coils.
6. Connect the cable and check what and where I ran away. If down frequency (then we wrap in the bottom of several turns on the mandrel 8mm) and thus correct the frequency and resonance we need!
With the help of MFJ-269, this design was vanished into the resonance at 145.5 MHz at CWS \u003d 1.0 RX \u003d 0 R \u003d 52.
Good luck in repetition: UA9JAI Surgut Serge-73!

X-200 is a two-way (144/430) column antenna with a circular orientation chart and a high gain coefficient.

The first such antenna was made in the late 90s and even still works. X-200 in English. Below is an antenna scheme:

The antenna is fully manufactured (including all coils) from a solid copper wire with a diameter of 2mm without intermediates. All coils are frameless. CONDACTOR C1 is made of SAT-703 coaxial cable segment 2 cm - it is possible to operate the system on the 70cm range. Capacitor C2 - Air, trimmed - they make an antenna setting.

Well, with the electrical part, everything is clear - we turn to the technical implementation.

The power load carried a wooden stalk from the shovel (only more powerful than in stores sell).

To him on the isolent (now the question can be solved more beautifully, definitely) is risen (so as not to overcertrine) the fiberglass fishing rod fit, inside which everything was placed, that was wound up with unbearable labor, i.e. The antenna itself, laid by foam pads from the bounce with all the coils (except L4 and capacitors).

In the cutting on 5cm below the coil L4 perpendicularly, but with a difference in a height of 5mm, two through holes were drilled - for future counterweights. A counterweights were inserted and disappeared. Schematically, their mount can be seen below:

Now setting.

First of all, you need to configure the parallel C1 / L4 circuit to the middle frequency of the 70cm range - it is whether it allows you to feed the entire design at these frequencies. The discharge point in L4 defines the transformation coefficient. Well, if you have nothing to check, then leave as it is. I never checked it too, because At that time, there was nothing.

I set up the setting only according to the testimony of the KSW meter directly in the room, placing the antenna horizontally. High ceilings allowed to do it. The setting is made by rotating the C2 rotor. It should be noted that if it does not manage to get the necessary indicators in coordination simultaneously in both bands, you need to choose a removal from the L4 coil.

As a result, I got very good indicators in coordination:

145 MHz - KSV \u003d 1.03

435 MHz - KSV \u003d 1.02

After tuning, an empty bottle from under the "sprite", which prevented all open parts from moisture was hoping from above. 10 years later, this bottle lost its green color.

Diamond F-23 antenna in one hour

In order to assemble this antenna, you need 4.5m aluminum wire with a diameter of 2.5mm, a copper wire with a diameter of 1.2mm, 1.5mm and a 4m plastic pipe with a diameter of 25mm.

Dimensions are shown in the figure. The coils are filled and fixed on flat textolite frames along the edges of foil and they are rumored coils. The matching coil is soldered to the case of the case. Butterpalite plate one side is soldered to the central output of the sequence, the opposite side solder the other output of the coil. Capacitor with a capacity of 5.6pf is inside the coil.

In the photograph of the coil, which I use. The elements of the antennas are attached with the help of electrical terminal workers who can work in the store. Terminals from brassly soldered to the sites to which the coils are already soldered.

All items starting from the top are assembled and attached with screws, after this, the antenna is carefully inserted into the plastic tube. To get rid of the effect of rattles, you can use a paralysis, or pieces of fiberglass equal to the inner diameter of the plastic pipe.

Mounting to the mast is carried out with a glass of 50mm with a height of 25mm (for moseliving). At a distance of 20 mm, from the top edge of the glass, three holes for a counterweight 5mm are drilled. The length of the counterweight is 51cm. Two washers in the figure are for the option of the collapsible antenna (2 to 2m).

I express my deep gratitude to Oleg RW4PJD for the possibility of removing samples from his antenna. Questions Please send to the address [Email Protected]

Diamond F-23 - Basic Range Antenna 144-174 MHz, 200 W, Strengthening 7,8 DBI

Attention! We deliver the original Diamond F23 Made In Japan antenna from Diamond!

(not chinese fakes - who are fully sold on different sites)

Vertical antenna for basic stationsDiamond F23. Designed for use in a 2 meter frequency range (144-174 MHz). The use of glass fiberglass coverage provides complete protection against bad meteorological conditions. The antenna comes with a durable aluminum fastening, providing fast and reliable installation on the mast. For convenient transportation, the fiberglass case is divided into three sections, and metal connecting clutches ensure the mechanical strength of the compounds.

Professional Vertical Collinear Verv Antenna Diamond F23. It can be used to organize professional communication networks in the range of 144-180 MHz, as well as as a basic antenna of an amateur radio station or a replay of a range of 144 MHz. It is made of high-strength materials and can withstand the wind gusts by speed up to 40 m / s.

Antenna Diamond F23. It is supplied in a disassembled form, the length of the packaging is 157 cm. When assembling sections, the sealability and the impossibility of falling inside the antenna is ensured. To configure an antenna to various frequencies in the range of 144-180 MHz, creation of the collinear internal elements of the antenna according to the attached trimming map. When using an antenna on an amateur range of 144-146 MHz, cropping items is not required, the antenna will be ready to work immediately after the assembly.

Antenna Diamond F23. It consists of three collinear elements of 5/8 wavelengths with capacitive loads that provide high gain (7.8 dBi) with a wide bandwidth (CWS in the range of 144-146 MHz no more than 1.45). Maximum power supplied to this antenna in World Cup mode can reach 200 watts, antenna height 4.53 m. Antenna is designed for nutrition coaxial cable With a wave resistance of 50 ohms, multiple for connecting the SO-239 type.

Basic vertical antenna Diamond F23. It has the following characteristics:

• Strengthening 7.8 DB
• Number of emitting elements --- 3 * 5/8
• Permissible power 200 W
• Weight of 1.7 kg
• Altitude assembly 4.53 m
• Machine on mast --- diameter 30-62 mm
• KSV value<1.5:1
• Bandwidth --- 3 MHz
• Permissible wind speed 50m / s
• Card Trimming on Dipan
• Russian assembly and configuration instructions!

Many do not understand the importance of good coordination of the Radio-line-and-antenna radio path. Or rather understand the importance, but absolutely unable to really assess the state of affairs. Most often, they are satisfied with the testimony of the built-in CWW meter close to one. The most unpleasant thing is that in the case of a poor state of affairs, the owner of the radio increases power until they become responsible. And how much power will appear on the television of a neighbor and leaves the atmosphere to warm up - the second question is ... We will try to figure out.

The picture shows a schematic diagram of three devices and two transitions between them.

The secret is that the KSV meter shows what he "sees" on the transceiver connector. The rest of the devices and impedances are "hiding behind the backs" in front of standing as one matristo inside the other. And at each transition and device, the losses caused by attenuation in the cable or transmission lines and bad CWS are suited. To begin with, we define with units of measurement. For specialists, for example in the field of agriculture, the term dibble is closer to medical than to the concept of "how many times." Therefore, to start a table of losses in dB and decoding in percent, in which everyone is well understood. And now the table of physical losses in the lines and places of compounds, depending on the range, calculated by the special program for modeling lines of transmission lines as well as loss with poor coordination.

Looking at this picture it is easy to agree that with an unfavorable scenario in the antenna, it can not get anything at all :-).

And now closer to radio engineering. If the antenna has a real impedance equal to the resistance of the transmission line, whether it is a coaxial cable, a quarter-wave transformer or a configured line, then the actual CWS of the antenna-feeder device (AFOU) will be measured on the KSV-METER transceiver connector. If not, the KSW meter will rather match the cable rather than with the entire system. Due to the fact that measuring the CWS directly on the antenna already raised above the Earth is very inconvenient, configured lines and a quarter or half-wave cable segments are often used to communicate with the antenna, as well as transformers that are exactly "transmitted" to the radio input (impedance). That is why if the antenna resistance is unknown, or only adjust it, it makes sense to apply a coaxial cable of a certain length. The above tables will help to choose from two angry the smallest - either losses in the feeder, or the loss of KSW :-). In any case, what I described above is better to know than to remain in ignorance ... When choosing, installing or configuring a particular antenna, you need to know several basic properties that can be described by the following concepts.

Resonant frequency

The antenna emits or receives electromagnetic oscillations with the greatest efficiency only when the frequency of the exciting oscillation coincides with the resonant antenna frequency. From this it follows that its active element, the vibrator or frame have such a physical size in which the resonance is observed at the desired frequency.

By changing the linear dimensions of the active element - the emitter, the antenna is configured into the resonance. As a rule, (based on the best ratio of efficiency / consideration and coordination with the transfer line), the length of the antenna is equal to half or a quarter of the wavelength at the central operating frequency. However, due to capacitive and end effects, the electrical length of the antenna is greater than its physical length.

The resonant frequency of the antenna affects: the proximity of the antenna location over the ground or some conductive object. If this is a multi-element antenna, then the resonant frequency of the active element can still be changed in one direction or another depending on the distance of the active element relative to the reflector or director. In the directories on the antennas, graphs or formulas are given to find the coefficient of shortening the vibrator in the free space depending on the ratio length ratio to the diameter of the vibrator.

In fact, the shortening coefficient is rather difficult to determine, because The height of the antenna suspension surrounding the subjects, the conductivity of the soil, etc. has a significant effect. In this regard, in the manufacture of antenna, additional elements of adjustment use in small limits to change the linear dimensions of the elements. In a word, "bring the antenna to the working condition is better at its location. Usually, if the antenna is a wire type of dipole or Inverted V, shocked (or extended) the wire connected to the central dwelling of the feeder. So fewer changes can be achieved more effect. Thus, set the antenna to the operating frequency. In addition, changing the inclination of the rays into the inverted V, adjust the minimum of the CWS. But this may not be enough.

Impedance or input resistance (or radiation resistance)

The smart word impedance denotes the complex (total) antenna resistance and it changes along its length. The maximum current and minimum voltage point corresponds to the smallest impedance and is called an excitation point. Impedance at this point is called input impedance. The reactive component of the input impedance on the resonant frequency is theoretically equal to zero. At frequencies above the resonant, the impedance is inductive, and at frequencies below the resonant - capacitive. In practice, the reactive component in most cases varies from 0 to +/- 100 ohms.

The impedance of the antenna may depend on other factors, for example, from the proximity of the location to the surface of the Earth or any conductive surfaces. In the ideal case, a symmetric half-wave vibrator has an emission resistance of 73 ohms, and the quarter-wave asymmetric vibrator (read the pin) - 35 ohms. In reality, the effect of land or conducting surfaces can change these resistance from 50 to 100 ohms for a half-wave and from 20 to 50 ohms for a quarter-wave antenna.

It is known that an antenna Inverted V, due to the influence of the Earth and other objects, it never happens strictly symmetric. And most often, the resistance of radiation in 50 ohms is shifted from the middle. (It follows one shoulder to shorten, and another increase on the same value.) For example, three counterweights are slightly shorter than a quarter of the waves located at an angle of 120 degrees in horizontal and vertical planes, convert the GP resistance into very convenient 50 ohms for us. And in general, the antenna resistance more often "customize" under the resistance of the transmission line than the opposite, although such options are also known. This parameter is very important when constructing the antenna power node.

Not specialists and not very experienced radio amateurs, for example, do not even realize that active elements in multi-band antennas can be connected physically not all! For example, a very common design, when only two is connected directly to the feeder, or even one element, and the rest are excited by re-empty. Even the slang word is - "reversal". Of course, it is no better than the direct excitation of vibrators, but very economically and greatly simplifies the design and weight. An example is the numerous constructions of three-band antennas of the UD-Yagi type and Russian yagi, including the designs of the XL222, XL335 and XL347 line.

Active nutrition of all elements is a classic, so to speak. Everything in science, the maximum bandwidth without duties, is much better than the FRONT / BACK ratios. But everything is always more expensive. And heavier 🙂 Therefore, a more mighty mast stretches behind this, the same turning, stretching area, etc. etc. For us, consumers, cost is not the last argument.

We should not forget about such a receipt as symmetrization. It is necessary to eliminate the "skew" when powering a symmetric antenna asymmetric power line (in our case, a coaxial cable) and makes significant changes in the reactive component of the resistance approaching it to a purely active.
In practice, this or a special transformer is called Balun (Balance-Unbalance) or simply a certain amount of ferrite rings, put on the cable near the antenna connection point.

Please note that when we say the "balun transformer", then we mean that the impedance is really transformed in this, and if it is just a baloon, then it is rather the throttle is included in the cable bracket.

Usually, even for the range of 80 meters there is a dozen rings (sizes on the cable, permeability of something from 1000nn and less). On the bands above and is less. If the cable is thin, and there is one or more rings of a large diameter, you can proceed on the contrary: to wind on the strain (CHA) several turns cable.
Important: from all turns that are placed, half it is necessary to wind up the other side.

In my dipole 80 meter range of 10 turns of the cable on the ring 1000nn, and on the three-band hexabime (spider) 20 rings are suitable on the cable. Their overall resistance (as inductance) at the operating frequency should be more than 1 kiloma. This will exclude a cable braid current, thereby achieving symmetric excitation at the connection point.

The most practical decision, in connection with its simplicity and efficiency, used everywhere - this is 6-10 turns of the power cable in the coil with a diameter of 20 centimeters (the turns should be fixed or on the frame or plastic guides so that the inductance is obtained, and not the cable bay :-). In the photo it can be clearly considered. This technique will work perfectly on your usual dipole. Try, and you will immediately notice the difference in the TVI level.

Gain

If the antenna emits the same power absolutely in all directions, it is called isotropic, i.e. Food diagram - sphere, ball. Really such an antenna does not exist, so it can still be called virtual. She has only one element - she has no amplification.

The concept of "strengthening" can apply only to multi-element antennas, it is formed by re-energizing the syphase electromagnetic waves and the addition of signals on the active element. We all know the situation with a bad connection of mobile phones in the countryside? And how do we decide? We find a long conductive subject and bring to it "Mobile" as close as possible. Communication quality increases. Of course, due to re-energization, the conductive base station signals found by us. Those who older may remember a similar situation with transistor receivers of 60s, listening to "Beatles". The same situation. This was especially noticeable on magnetic antennas: due to the large number of turns of the magnetic antenna, the above-handed voltage was larger. A special case, sometimes consume the word "strengthen" in relation to a single pin to determine how much the vertical component of the radiation is less than the radiation in the horizontal plane. A priori is not an amplification - it is rather a transformation ratio 🙂 Do not confuse with phased or collinear verticals: they have two or more elements in them, and they have a real gain. The gain coefficient can be obtained by concentrating the radiation energy in one direction. Strengthening is formed due to the addition-subtraction of radio waves excited in the vibrator and re-empty director. On an animated drawing, the resulting wave is shown by green.

The directional action coefficient (CBD) is a measure of increasing power flow due to the compression of the radiation pattern in some one direction. Antenna may have a high KND, but a small gain, if the ohmic losses in it are large and "eaten" the useful voltage obtained by re-energization. The gain coefficient is calculated by comparing voltage on the measured antenna, with a voltage on the reference half-wave dipole running at the same frequency as the measured antenna, and the same distance from the transmitter. Typically, the gain coefficient is expressed in decibels with respect to the reference dipol - DB. More precisely, it will be called dBD.. But if you compare with a virtual, isotropic antenna, then the value will be expressed in dBI And the number itself will be somewhat more, because the dipole still has some directed properties - maxima in the direction perpendicular to the canvas, if you remember, but there is no isotropic antenna. There is a smaller number in the denominator, therefore the attitude is greater. But you do not "enter" on them, we practice, we always look at DBD.

Foci Chart

The antennas are trying to design in such a way that they have the maximum gain coefficient (taken and passed) in a predetermined direction. This property is called orientation. Animation shows a dynamic drawing of addition-subtraction excited in the vibrator and re-empty reflector and director of radio waves. Green color indicates the resulting radio wave.

The nature of the antenna radiation in space is described by a pattern of orientation. In addition to radiation mainly (the main) direction, there are side radiation - rear and side petals.

The transmitting antenna pattern can be constructed by turning it and measuring the field strength at a fixed distance and without changing the transmission frequency. These measurements are transformed into graphical form give a representation in which direction antenna has a maximum gain factor, i.e. The polar diagram shows the direction in which the energy emitted by the antenna in horizontal and vertical planes is concentrated. In amateur practice, this is the most complex type of measurement. Conducting measurements in the near zone it is necessary to consider a number of factors affecting the accuracy of measurements. Any antenna except the main petal has a number of lateral petals, in the range of short waves we cannot raise an antenna for a large height. When measuring the radiation diagram in the range of the side petal, reflected from the Earth or from the near building, it can get to the measuring probe, both in the phase and in antiphase, which will result in error in measurements.

The orientation diagram is also a simple wire antennas. For example, the dipole - eight with deep dips in the chart that is not good. The most popular antenna Inverted V.

If all the textbooks on radio engineering or Rothhamel are well remembered, then the inverted (dipole) has an o-dimensional diagram. Those. There are deep failures. And if you change the position of the canvas, change one pair places (moving the canvas of one antenna, for example, at an angle of 90 degrees), the diagram begins to approach conventionally in thick sausage. But the most important thing is to disappear the failures, and the diagram "is rounded". Diple has enough to change the angle between halves. And if you do this angle from a wave dipole to 90 °, then with some stretch the radiation diagram can be called circular.

Bandwidth

As a rule, two classes of antennas distinguish: narrowband and broadband. It is very important that in the operating frequency interval supported good matching and a given strengthening. The bandwidth of the antenna should not change when the transmitter or receiver frequency is restructuring. Narrowband antennas include all simple resonance antennas, as well as directed such as the "wave canal" and "square". Me, like an avid telegraphist, quite suit antennas with a strip of 100 kHz, but there are universals, SSB lovers, so the manufacturers of the antennas are trying to provide a bandwidth equal to the width of the radio amateurs. For example, an antenna of the wave canal "on the radio amateur range of 14 MHz should have a bandwidth of at least 300 kHz (14000 - 14300 kHz) and, moreover, good matching in this frequency band. Broadband antennas are characterized by a large frequency change range, in which the operating properties of the antenna are preserved, many times superior in this respect resonant systems. These include speakeriodic and spiral antennas.

Efficiency ratio (efficiency)

A portion of the power supply to the antenna is emitted to the space, and the other part in the antenna conductors turns into heat. Therefore, the antenna can be represented as an equivalent load resistance consisting of two parallel components: radiation resistance and resistance of loss. The effectiveness of the antenna is characterized by its efficiency or the ratio of the beneficial (emitted) power to the total power supplied to the antenna. The greater the resistance of radiation in relation to the resistance of the loss, the greater the KGID antenna. It is quite obvious that good electrical contacts and small ohmic resistance (the thickness of the elements) is good.

As you can see, this parameter is interested in us in the all-day queue and is not the main thing. (God forbid you think that his bad meaning can not be upset. If the KSV is more than two - it is bad). If the antenna is configured to the resonance and during the setting, we compensated for its reactivity, and agreed with feeder feeder by resistance, then the KSV will be equal to one. Just do not use the device built into the transceiver as an ARV meter. He is more indicator. Plus, a vehicle is not always discouraged. And we want to know the truth. 🙂 And do not forget about symmetrization (see above). It is known that you can power the antennas with a coaxial cable any length, then it is an asymmetrical coaxial cable, but in the case when two antennas are powered by one cable, it is better to make sure that for both calculated frequencies, the length of the cable is a multiple half-wave.

For example, for a frequency of 14,100, the cable length should be:
100 / 14.1 x 1; 2; 3; 4, etc. \u003d 7.09m; 14,18m; 21,27m; 28.36m, etc.

For 21,100 MHz, respectively:
100 / 21.1 x 1; 2; 3; 4, etc. \u003d 4.74m; 9,48m; 14,22m; 18.96m; 23.70; 28.44, etc.

Usually, the people consider the minimum length of the feeder to be a priority, and if you calculate some large lengths, we will see that for ranges 15 and 20 meters the first "multiplicity" will come with a cable length of 14.18 and 14.22 meters, the second, respectively, 28.44 meter and 28.36 meters. Those. The difference in the 4-re centimeter, the PL259 connector is long. 🙂 This magnitude is neglecting and have one feeder for two antennas. Calculate the "multiple length" of the feeder for bands 80 and 40 meters for you is now not difficult. If we have not forgotten about symmetrization, now we can customize the antenna with confidence that the feeder does not make any interference to the purity of the experiment. Very good option Two double inverters on two masts: 40 and 80 + 20 and 15 meters. With this option (well, another GP is 28 MHz in case there is a passage) EN5R leaves almost all expeditions.

Well, now we are armed with theoretical knowledge of the properties of the antennas and adequately can perceive tips on their execution and configuration. Of course, all theoretically, because you are visible in place. The most popular among the antennas for radio amateurs - dipole. So, the original conditions: we can lift-omit the dipole for half an hour and many times a day. Then, most likely, it makes no sense to spend time to pre-configure it on Earth: it will not be easy to perform for its work at the height of the suspension. From preliminary theoretical knowledge, you will only need information that the dipole's working frequency near the ground with the rise "will leave" up 5-7 percent. For example, for a 20 meter range is 200-300 kHz.

To configure in a resonance with a working frequency of a conventional dipole, you can use (except the system to lower-cut-raise) or the SVIP-GENARATOR (many know this device under the name of the GCC), or a gir or, at worst, exercise and oscilloscope. It is clear that if there are no such devices, you will have to adjust the dipole web into the resonance using an ordinary field indicator, or as it is also called the probe. This is a conventional dipole with long cloths at least ten times less than the calculated length of the antenna itself, connected to the rectifier bridge (better on Germany diodes - will respond to less voltage) loaded to the usual arrow device - a microammeter with a maximum scale size (better It was visible). It will be better if the probe is with a circuit (filter) to the operating frequency, so as not to tune in to the neighbor's mobile phone, and with an amplifier. For example, such. It is clear that you caught the length of the dipole to the maximum of its radiation at the operating frequency. The minimum of the CWW in this case should form a machine gun. If not, remember the symmetrization. If it does not help and the value of the KSV is still high - you have to recall the methods of coordination. Although it happens very rarely.

The following composition is a few dipoles on one cable. Well, read about the cable above, and about the web should be aware of the following: for their minimal effect of one on another, they should be stretched at an angle of 90 degrees. If there is no such possibility, then after the correction is the length of one, most likely it is necessary to adjust the other. Several Inv V. one cable - the option described above and is distinguished only to the fact that it is possible to "push" the CWS to the minimum value to the angle of inclination to vertical (to the mast), which, of course, is easier than making a matching device and even easier to another Fit dinna canvas.

So, it turns out that the sequence of actions should be performed - first the antenna is set to resonance, and then achieve a minimum CWW in the required frequency band. All this is true for simple dipole antennas. And it is very complicated, in case the antenna is multi-element. In this embodiment, without special devices, it is not necessary to do without only a system with several unknown, but also achieve quite certain directed properties.

The setting includes the measurement of the basic parameters of the antenna and the correction of them by fitting the linear dimensions of the antenna elements, distances between the elements, the settings of the matching and symmetrical devices. Tip: Trust Specialists. As the famous Belarusian shortwave spoke Vladimir Prikhodko EW8AU, "setting up an antenna only on the CWS, it is possible to make a good agreed load from the antenna for the output cascade of the transmitter. It will work well in normal mode, only an antenna can have a bad radiation pattern, low efficiency, part of the power will be spent on heating the antenna elements and the antenna feeder path and the most unpleasant thing, which may be for the radio amateur - this is interference with television " .