A wide-range transformer that moves on a ring ferite core.

Golovna

When working with an additional imported transceiver in conjunction with its old, reliable tension (RA), which most likely served as a source of long-lasting fate, a situation often arises when the tension of awakening RA disappears .The reason is the large input support RA, which is divided into the output support of the transceiver.

For example, the input input RA from OS:

x GU-50 lamps are close to 85 Ohms;on 4 G-811 lamps it is close to 75 Ohms;

ontwo GK-71 close to 200 Ohm;

3.5 MHz - 77 Ohm;7 MHz - 128 Ohm;

21 MHz - 54 Ohm;28 MHz - 88 Ohm.

The method is incredibly good, it gives us a good SWR of no more than 1.5, but requires 6-9 circuits and two layers of jumpers.

In Fig. 1b is a diagram of an HF transformer with a support transformation ratio of 1 ׃ │ ≥4…≤9 │ , The same applies to the connection point for the output.

If the input support RA is less than 200 Ohms, then the winding of the transformer follows the circuit in Fig. 1a, and if it is more than 200 Ohms, or less than 450 Ohms, then it follows the circuit in Fig. 1b.

Since the input signal of the RA is unknown, then prepare a transformer for another circuit, which, if necessary, can be switched to the first option.

To do this, you will need to turn off the middle winding and connect the rest, as in Fig. 1a.

The transformer windings are wound simultaneously for the first option, two, and for the other - three with wires, slightly twisted, making 8 turns.

With this type of skin turn of one side, try to remove the appearance of the ring (twisting).

Then the head of one winding is connected to the end of another, and the head of another winding is connected to the end of the third, in which the leads are formed. PETV wire with a diameter of 0.72…0.8 mm. The ring (ring) needs to be wrapped in front with a stitch of fluoroplastic or varnished fabric.

Photo No. 1 shows two HF transformers, Wikonan for another option. Photo No. 1. .

One transformer without twisting of wires (in one row), soldering with leads on the jumper strip, other (

at 28 MHz – 1.5 – 1.65. When the transformer is turned on behind the first circuit, the PKS is even more beautiful.

The transformer is turned on between the input connector RA and the transition capacitor, which goes to the lamp (to the cathode).

If this is possible, it is necessary to install a multi-year pump.

Since there is no such possibility, then a compromise will have to be found, it will be necessary to find one input type of transformer winding with an acceptable SWR on all ranges. Select the output and adjust the SWR trace for RA operation in the work pressure mode. To use the transceiver with the RA, you can use simple devices based on the G-filter according to the diagram in Fig. 2 near the block that connects between the transceiver and the RA with short sections of RF cables.

1. Fig.2The coil is frameless - 34 turns,

2. wound on a mandrel with a diameter of 22 mm with a 1.0 mm dart. The outlet at the entrance is split through 2+.2+2+3+3+3+4+4+5 and another 6 turns. The coil is completely bent and soldered with short leads to the contacts of the biscuit jumper.

At position 1 of the jumper, the coil shorts out (the “bypass” switches on), and at position 11, the entire coil is connected.Double capacitor for lamp components. The replacement of the exchangeable capacitor can be selected for the constant range of the skin, which is interconnected with another device.

4. Such a control system allows you to use a transceiver and PA with an input support of 60 - 300 Ohms. (photo No. 2). Photo No. 2

5 .I. S. Lapovok. I will be a HF radio station - Moscow, Patriot, 1992. z.

137, p.

153.

V. Kostichiv, UN8CB m. Petropavlovsk. The power supply of the input antenna support with the feeder support, as well as the sizing of antennas for radio amplifiers, has always been relevant.

In the rest of the years, special interest is shown in transformative and useful devices on ferite rings.

Therefore, such devices can be small-sized, with a high (up to 98%) efficiency factor. In addition, they do not exhibit resonant power when blocking the frequency interval of tens of octaves (for example, from 1 to 30 MHz), which is especially handy if you are victorious Wide range antennas

(“squares”, “INVERTED V”, 3-element tri-band “hinged channel”, etc.).

In such wide-skin transformers, the windings are made of double-wire long transmission lines (based on coaxial cable or single-core), wound on a ferite ring.

This type of winding allows you to practically reduce the inductance of the outlet and change the inductance of the windings.

The level of designation of the transformer on long lines (TDL), taken from the statistics, with one winding of the double-wire line is shown in Fig.

Obviously, the conductors of the long-term line shunt the generator and the generator, as in-phase streams flow through them.

The introduction of the magnetic circuit sharply increases the inductance of the winding, thereby moving the support of the common-mode current and sharply changing its shunting action.

At the same time, the magnetoconductor does not flow into the widened area, so that the flow mode is ensured to run (Rg=g=Ri).

There are a number of ways to ensure TDL with a whole coefficient of transformation of the item. It is possible, for example, to adhere to the offensive rule.

The windings (they may be n) are made from equal electrical power supply lines.

The skin winding is placed on an adjacent ring magnetic conductor of the same type.

Enter the line from the side that is moving, connect sequentially, and from the bottom - in parallel.

In general, the circuit diagram for switching on TDL with a whole transformation coefficient is shown in Fig.

4.

Here the fair relationship is Rg=n2Rn, U1=nU2, g=nRn.

In Fig.

5 images of different options for turning on TDL.

It is possible to operate the TDL on one magnetic conductor, but in this case it is obligatory to adjust such possibilities.

First of all, the number of turns of the skin line is proportional to the value of the common-mode voltage that exists between the ends of the line; the winding fragments are connected by an underground magnetic flux.

In another way, the geometric doves of all lines tend to sway, but remain the same.

Depending on the option of turning on the TDL, you may find that these lines are often or most likely not located on the magnetic circuit.

To calculate the number of turns in the windings, it is necessary to calculate the values ​​of the common-mode voltage Vk on the skin line.

When using the “whip channel”, the input impedance is 18.5 ohms, with a 75 ohm coaxial cable for additional TDL (inclusions behind the diagram in Fig. 5, d) with a transformation coefficient of 2, the ratio of the turns of the windings is the same w1: w2 = (2 + 1/2-1: (2 + 1/2-2) = 3: 1. This means , That on the magnetic circuit, the upper winding along the small one is completely faulty, while the other winding is only a third.

If the voltage of the lines for the windings is much less than the voltage of the working winding, the TDL can be simplified: the lines, and the common-mode voltages, reach zero.

replace with a jumper.

In this case, for example, the tri-winding TDL (Fig. 5, e) is converted into a double-winding one (Fig. 6).

The transmission coefficient TDL depends on the extent to which the power supply is at the optimum value and the relationship between the electrical line and the power supply.

If, for example, the required value is doubled, then the loss in TDL reaches 0.45 dB when the lambda/8 line increases and 2.6 dB when lambda/4.

In Fig.

7 shows the level of the TDL transmission coefficient with n=2 as a phase extension of the line for three values ​​of g.

The analysis shows that, as the lines with optimal values ​​are determined, the coefficient of standing pressure in the TDL does not exceed 1.03 when the line lambda/16 is increased and 1.2 when the lambda line is increased 8.

It is possible for the connection to go unnoticed, so that the TDL parameters are no longer sufficient when the line lines reach less than lambda/8.

The output data for the expansion of the TDL is the transformation coefficient, the option of turning on the TDL, the lower and upper limits of the operating frequency range (in hertz), the maximum tension Pmax on the vantage (in watts), the support of the vantage Rn (in ohms) i support the feeder g (in ohm).

The development should be carried out in the following order.

1. Determine the minimum inductance of the line conductor Ll (in generation) for the reason that

Ld>>Rg/2fn.

The magnetic conductor is selected carefully so that it is not saturated with in-phase flow (or constant, as it is).

For which, the magnetic induction in the magnetic circuit is an order of magnitude less than the saturation induction (taken from the sources).

5. Find out the peak voltage Up at the line:

de y - SWR at the feeder.

6. Calculate the effective value of the current Ief (in amperes):

7. Calculate the diameter d of the darts (in millimeters) of the long line:

de J – permissible thickness of the strum (in amperes per square millimeter).

For TDL of narrow antenna devices, ring (types K55X32X9, K65X40X9) magnetic conductors with ferrites 300VNS, 200VNS, 90VNS, 50VNS, as well as 400NN, 200NN, 10 are suitable. The magnetic core parts can be folded into several rings.

View
Croc twist, cm

I I

X * With a wire diameter of 1 mm.** With a dart diameter of 0.33 mm.

In order to complete the parameters (size, asymmetry coefficient) and simultaneously simplify the design of the uniform-transforming unit, establish a consistent connection of TDL decals of a different type. For example, according to the established methodology, TDL warehouses with n=2 are sorted out. You must ensure the input reference is 12.5 ohms

symmetrical antenna

With coaxial cable RK-50.

The lower operating frequency is 14 MHz.

The tension does not exceed 200 W.

For TDL, a vicorized magnetic conductor of standard size K45X28X8 (dcp = 3.65 cm, S = 0.7 cm 2) with 100NN ferite is transferred (their saturation induction is 0.44 T/cm 2).

Let the first stage with the transformation coefficient n=2 of the folded TDL (Fig. 8) be included behind the circuit in Fig.

5 a, a friend (z n=1)

V1=(2-1)71=71 V. If the common-mode voltage of the other winding remains at 0, then this winding is replaced by jumpers (Fig. 6).

5. In-phase stream is ancient:

6. We calculate the magnetic induction in the magnetic circuit:

B = 4 * 10 -6 * 100 * 9 * 0.06 / 3.65 = 59 * 10 -6 T, which is significantly less than the saturation induction.

Line support g1 = 50 Ohm.

The other TDL has the same rings as the first one.

Todi Ll=13.5 μH, w=9 turns.

7. Common-mode voltage on the winding V=(2+1/2-1)71=106.5 St.

8. In-phase stream is ancient:

L = 106.5 / 2 * 3.14 * 14 * 10 6 * 13.5 * 10 -6 = 0.09 A.

9. Magnetic induction

B = 100 * 4 * 10 -6 * 9 * 0.09 / 3.65 = 89 * 10 -6 T.

And in this case it will be less due to the induction of saturation.

Select a winding line support close to 12 Ohms.

The diameter of the wires for TDL lines is determined in the same way as the diameter of the wires for winding in basic transformers.

This rozrakhunok is not to be visited here.

Dear reader, you may note an inaccuracy in the indicated breakdown (due to the stagnation of warehouse TDL).

The point is that the inductance Ll is calculated without taking into account the fact that the TDL windings of the first and the other stages are connected, then with a large margin.

TDL with transformation factor n=2 (NS type), power supply up to 200 W, which uses a 75-ohm feeder support with a symmetrical antenna input, which has an 18-ohm input support.

can be produced on a 200NN magnetic core (Fig. 13) with a standard size of K65X40X9.

The windings contain 9 turns of line from PEV-2.1.0 wires.

The prepared transformer is MAV KKD 97%, asymmetry coefficient at a frequency of 10 MHz – 20, at a frequency of 30 MHz – not less than 60.

In Fig.
Figure 14 shows the switching diagram of a warehouse TDL (CP type) with a transformation factor n=3, which uses an antenna with a 9 Ohm input support, with a 75 Ohm coaxial cable.
TDL, insurance coverage is used in the range of 10...30 MHz at a pressure of up to 200 W, mounted on rings (type size K32X20X6) with ferrite 50VNS.
The magnetic conductors of transformers WT1 and WT2 are folded into two rings, the windings and coil L1 contain 6 turns each.
Long lines and coils are wired with PEV-2 1.0 wire.

The line support for WT1 is 70 Ohm, for WT2 – 25 Ohm.

Aspirations TDL mav CCD 97%, asymmetry coefficient – ​​not less than 250.

The output is applied to the transformers of high-frequency devices, which are detected when receiving radio transmissions and boosters in the HF-UKH range.

High-frequency high-frequency transformer of the long-line type (Alekseev O.V., Golovkov A.A., Polovy V.V., Solovyov A.A. “Broadband radio transmitting devices. L., Zvyazok, 1978, page 155, Fig. 8.14 b), which consists of ferite tubes or a set of ferite rings, in the middle of any rooms there is an HF cable.

Closest to proven technical solutionsє high-frequency transformer (V.V. Shakhgildyan. “Design of radio transmitting devices.” Leningrad, Radio and Communications, 1984, page 176, Fig. 4-20b), considered as a prototype of the “single-thread” transformer design, in which HF The cable, which creates a turn of the transformer, is passed through two cylindrical ferite cores.

According to the prototype, when the HF tension in the cable increases, the value of the magnetic induction changes along the radius of the ferite core, and therefore the tension of the input, which determines the temperature of the entire device.

The technical problem, solved by the output, lies in the primus-type power supply through the core of high-frequency magnetic fields, with a flexible cable in line with the axis of the core.

In tight HF transformers, the internal diameter of the core must be chosen to be slightly larger, lower than the radial size of the cable, which is located in the middle of the core.

It is necessary to change the change in magnetic induction in relation to the radius of the core, since it changes proportionally to the axis of the conductor with the strum, which is located in the middle of the core.

Therefore, with an increase in the radial dimensions of the core, the intensity of magnetic induction on its internal and external surfaces decreases, and then the intensity of the costs changes, as seen There is in these areas, and the temperature of the ferite core.

In the middle of the ferite core 1 (Fig. 1), folded with adjacent rings, a cylindrical tube 2 of electrically conductive material is installed on its inner surface.

The edges of the tube with jumpers 3 and 4 (made from the same material as the tube) are connected to additional conductors 5, 6 with a braided coaxial cable 7, routed in the middle of the tube.

The result is a flow that is indicated by the difference in potentials between the braided cables, not along the outer surface of the braided cable, but along the surface of the inserted cylindrical tube 2 along jumpers 3, 4 and conductors 5, 6. In this case, the cable is not pulled out in the middle of the cylindrical tube on the strim in the middle of the cable, not on the strum on the outer surface of the cylindrical tube.

In the middle of the volume, which is indicated by the cylindrical surface and the interconnecting jumpers, the cable can be extended quite a bit, for example, as shown in the small figure of Fig.

It is applied to the electrical power industry and is intended for the interconnection of magnetic fields of power frequency, created in large spaces in large administrative buildings with electronic and technical equipment, for example relay protection and automation, or in residential areas with single-phase electric reactors without a ferromagnetic core.

It is applied to electrical engineering and is intended for the interconnection of equal magnetic fields of industrial frequency, which are created in large spaces in large, administrative buildings or residential areas by single-phase electrical reactors without ferromagnetic core.

Various types of transformer equipment are found in electronic and electrical circuits that are needed in many areas. sovereign activity.

For example, pulse transformers (below the text IT) are an important element that is installed in almost all current living units.

Design (types) of pulse transformers

• Depending on the shape of the core and placement on a new coil, IT is produced in the following structural designs:
  
• strizhneviy;
  
• reservation;
  
• toroidal (does not hurt the coil, the wire is wound around the insulating core);
  

armored stripe;

• The little ones are marked with:
• A – magnetic conductive circuit, made from grades of transformer steel, produced using the technology of cold or hot rolled metal (behind the core of a toroidal shape, it is prepared from ferrite);
• B – coil made of insulating material

C - darts that create inductive coupling.

It is important to note that electrical steel contains few additives to silicon, and the resulting waste leads to a loss of tension due to the flow of vortex jets onto the magnetic circuit.

In IT toroidal wicking, the core can be vibrated from rolled or ferrimagnetic steel.

The plates for the set of the electromagnetic core are selected according to the frequency. If this parameter is increased, it is necessary to install plates of smaller thickness. Robot principle

Shown below

The primary winding receives pulse signals that have a rectangular shape e (t), the hour interval between which is short.

This causes an increase in inductance over the hour interval t u , after which there is a decline in the interval (T-t u).

Induction drops occur due to liquidity, which can be expressed after a constant hour using the formula: p = L 0 / R n

• The coefficient that describes the difference in the inductive difference is calculated as follows: ∆B = max - r
• max – the level of the maximum induction value;

They have r-oversupply.

The greatest difference in induction is represented by the small unit, which reflects the displacement of the operating point in the IT magnetic circuit.

As can be seen on the hourly diagram, the second coil draws the same voltage as U 2 in any given gate.

This is how the energy accumulated in the magnetic circuit manifests itself, which is stored due to magnetization (parameter iu).

The impulses of the stream, which pass through the primary coil, are divided into a trapezoidal shape, and the fragments of the stream are drawn and linear (violations of the magnetization of the core) are united.

• The voltage level in the range from 0 to t u is lost to the unchanged value t = U m .
• What is the voltage on the second circuit, it can be calculated by calculating the formula:

with this:

Ψ – flux flow parameter;

S is the value that represents the cross-section of the magnetically conductive core.

In addition, the flow rate, which characterizes the change in the flow that passes through the primary coil, is constant, and the level of induction in the magnetic circuit increases linearly.

Based on this, it is permissible to substitute the difference of indicators collected at the same hour interval, which allows you to make changes to the formula:

In this case, ∆t is correlated with the parameter t u, which characterizes the voltage through which the input voltage pulse flows.

To calculate the area of ​​the pulse with which the voltage is generated in the second winding IT, it is necessary to multiply the two parts of the front formula by t u.

• As a result, we come to a virus that allows you to remove the main IT parameter:
• U m x t u = S x W 1 x ∆V
• Please note that the parameter ∆B is directly proportional to the value of the impulse area.
• Another important value that characterizes the IT robot is the induction drop, which is influenced by such parameters as the cross-section and magnetic penetration of the core of the magnetic circuit, as well as the number of turns on the coil:
• Here:
• U r is the value of excess induction;
• max – the level of the maximum induction value.
• H m – magnetic field voltage (maximum).

Doctors, that the inductance parameter IT is completely dependent on the magnetic penetration of the core, during expansion it is necessary to leave the maximum value µa, as shown by the magnetization curve.

It is obvious that in the material from which the core is made, the level of parameter r, which represents excess induction, is to blame for the minimum. Video: report description

based on the operating principle of a pulse transformer

Considering this, due to the role of the IT core material, a stitch made of transformer steel is ideally suited.

You can also use permal, which has a minimum coefficient of straightness.

High-frequency IT is ideally suited to cores made of ferrite alloys, since this material suffers from minor dynamic losses.

But through its low inductance it is possible to operate IT on a large scale.

Design of the pulse transformer

Let's take a look at how you need to work on IT.

• Dearly, I will attach the KKD to accurately calculate.
• As an example, let’s take the scheme of the initial transformation, in which IT is toroidal in appearance.

• First of all, we need to calculate the level of tension IT, for which we use the following formula: P = 1.3 x P n.
• The value of Pn reflects how much tension is compatible with pressure.

After this, the overall tension (RGB) is not less than the responsibility for the tension:

Parameters required for calculation:

S c – represents the area of ​​cross-section of the toroidal core;

S 0 - the area of ​​the window (as the pressure of the center and the front value is shown on the baby);

At max – the maximum peak of induction, which is determined by the type of ferromagnetic material being determined (the maximum value is taken from the device that describes the characteristics of the brands of ferrites);

f is a parameter that characterizes the frequency at which the voltage changes.

The next stage is reduced to the number of turns in the first winding Tr2:

If you have problems with the basic IT parameters, you can find thematic sites on the Internet that allow you to online modes open up any pulse transformers.

Transformers on ferite tubes have several functions: transform the supports, balance the currents in the antenna arms and suppress the currents on the outer surface of the braided coaxial feeder. The finest ham ferite material for wide-smooth transformers

(SHPT) is ferrite grade 600NN, but pipes and parts of magnetic conductors were not produced from it. Ferrite tubes from foreign companies are now available for sale good characteristics , zocrema, FRR-4.5 and FRR-9.5 (Fig. 1), which have dimensions dxDxL 4.5x14x27 and 9.5x17.5x35 mm identically. The remaining tubes were used as interference suppressors on the cables to be connected

system units

computers with monitors on electron tubes.

In fact, they are massively replaced with matrix monitors, and the old ones are thrown out at once with spare cables. Rice. 1. Ferite tubes Several ferite tubes, folded in two arms, create the equivalent of “binoculars”, on which you can place the windings of transformers that cover all HF ranges from 160 to 10 meters.

The tubes have rounded edges, which makes it difficult to damage the insulation of the winding wires.

From various circuits of wide-angle transformers, I will simply put it simply, with separate windings, the turns of which are drawn additional link connection of supports.

A transformer with a ratio of 1:1, similar to the choke, balances the currents in the antenna arms and reduces the currents on the outer surface of the braided cable.

Other transformers can be used to transform the base in addition to others.

What to worry about when choosing the number of turns?

In other minds, transformers with a single-turn primary winding run approximately four times higher than the high-lower range of the transmission is equal to the double-turn, and the upper frequency of the transmission is significant. Therefore, for transformers that are used in ranges of 160 and 80 meters, it is better to use double-turn options, and for 40 meters and more often single-turn options. It is important to select the correct number of turns in order to preserve symmetry and distribute the windings on the opposite side of the “binoculars”.

It is more important to evaluate the current characteristics of the transformer.

Why do you need strength and the equivalent of avantagement, creating the necessary tension?

The same circuit with two transformers is being analyzed. Vimir is carried out at the lower operating frequency. Step by step raising the tension of the CW and pushing it up around the hip, the temperature of the ferrite is determined by hand.

Rhubarb, in which the ferrite begins to heat up slightly, is important to the maximum allowable value of this transformer.

On the right, when working, it is not the equivalent of vantage, but a real antenna that reacts to the reactive storage input impedance, the transformer transmits the reactive voltage, which can saturate the magnetoconductor and trigger additional heating. 07.12.2016

In Fig.

• Figure 2 shows the practical design of the transformer, which has two outputs: 200 Ohm and 300 Ohm.
  Rice. 2.