Motorized configuration of the output circuit of the amplifier of a sq. Cold tuning P-circuit. Circuit solutions used in professional communications

Output P-contour and its features

P-contour must meet the following requirements:

Tune in any frequency of a specified range.

Filter, to the desired degree, signal harmonics.

Transform, i.e. Ensure optimal load resistance.

Have sufficient electrical strength and reliability.

Have a good efficiency and a simple, comfortable design.

The limits of the real possibility of the P-circuit, on the transformation of the resistance, quite high and directly depend on the loaded quality freight of this P-circuit. With an increase of which (therefore, an increase in C1 and C2), the transformation coefficient rises. With an increase in the loaded Quality of the P-circuit, the harmonic components are suppressed better, but due to the increased currents of the efficiency of the circuit drops. With a decrease in loaded quality, the efficiency of the P-circuit rises. Often contours with such a low-loaded quality rate ("squeezing of power") do not cope with the suppression of harmonics. It happens that with a solid capacity, a station operating on a range of 160 meters is heard and on the range
80 meters or a 40 metering range operating on a 20 meter range.
It should be remembered that the "spitters" of the P-contour is not filtered out, because they are in its bandwidth, only harmonics are filtered.

ROE effect on amplifier parameters

How does the resonant resistance (ROE) affect the amplifier parameters? The smaller the ROE, the amplifier is more resistant to self-excitation, but the coefficient of amplification of the cascade is less. Conversely, the more ROE, the gain is larger, but the stability of the amplifier to self-excitation decreases.
What we see in practice: Take, for example, a cascade on the G78B lamp, made according to a circuit with a shared cathode. The resonance resistance of the cascade is low, but the steepness of the lamp is high. And on this we have, with this steepness of the lamp, a large coefficient of amplification of the cascade and good resistance to self-excitation, due to low ROE.
The stability of the amplifier to self-excitation also contributes to low components in the control grid circuit.
The increase in ROE reduces the stability of the cascade in quadratic dependence. The greater the resonant resistance, the greater the positive feedback through the passage capacity of the lamp, contributing to the emergence of self-excitation of the cascade. Further, the lower ROE, the larger currents flow in the circuit, and hence the increased requirements for the manufacture of the output contour system.

Inversion P-contour

Many radio amples in the process of adjusting the amplifier met with such a phenomenon. This happens, as a rule, on bands 160, 80 meters. Contrary to common sense, the capacity of the alternating condenser with an antenna (C2) is unabled to small, less than the capacitor capacity of the setup condenser (C1).
If you configure the P-contour to the maximum efficiency at the highest possible inductance, then the second resonance occurs at this border. P-contour with the same inductance has two solutions, that is, two settings. The second setting is the so-called "inverse" P-contour. It is called so that the C1 and C2 containers were changed in places, i.e. the "antenna" capacity is quite small.
This phenomenon described and calculated a very old developer of equipment from Moscow. In the forum under Tick Real, Igor-2 (UA3FDS). By the way, Igor Goncharenko was very promoted when creating its calculator to calculate the P-circuit.

Ways to turn on the output P-loop

Circuit solutions used in professional communications

Now about some circuit solutions used in professional communications. The sequential power of the transmitter output cascade is widely used. As C1 and C2, variable vacuum capacitors use variables. They can be like a glass bulb and from the radio porcelain. Such capacitors of variable containers have a number of advantages. They do not have a sliding current of the rotor, the minimum inductance of the conclusions, as they are ring. Very small initial capacity, which is very important for high-frequency bands. Impressive Quality (Vacuum) and Minimum Sizes. We will not talk about two liter "banks" for a capacity of 50 kW. About reliability, i.e. On the number of guaranteed rotation cycles (there - here). Two years ago, the elder of the RA made on the GA43B lamp, which used the KP type 1-8 vacuum
5-25 PF. This amplifier worked for 40 years, and will still work.
In professional transmitters, vacuum capacitors of the Capacity (C1 and C2) by the separator capacitor are not separated, it imposes certain requirements for the working voltage of the vacuum kpa, because the cascade sequential power circuit is used there and therefore the operating voltage of the kPE is selected with a three-time reserve.

Circuit solutions used in import amplifiers

In the contour systems of import amplifiers made on G74B lamps, one or two G84B, G78B, power solid and FCC requirements are very rigid. Therefore, as a rule, the PL-contour is used in these amplifiers. As C1, a two-section capacitor variable container was applied. One, low tank, for high-frequency ranges. In this section, a small initial capacity, and the maximum capacity is not large enough to configure in high-frequency bands. Another section, greater container, is connected by a gallery switch to the parallel to the first section, to work on low-frequency bands.
The same gallery switch switches the anode throttle. On high-frequency bands, low inductance, and the rest is complete. The contour system consists of three to four coils. Loaded quality is relatively not high, therefore, the efficiency is high. The use of the PL-Crash leads to minimal losses in the contour system and good harmonic filtering. On low-frequency bands, the contour coils are performed on Amidon rings.
Quite often, I communicate on Skipe with a friend of Church, working in Acom. That's what he says: lamps installed in amplifiers are pre-train on the stand, then tested. If two lamps are used in the amplifier (ACOM-2000), pairs of lamps are selected. No paired lamps are installed in ACOM-1000, where one lamp applies. The circuit setting is performed only once in the stage of the stage, since all components of the amplifier are identical. Chassis, placement of components, anodic voltage, these throttle and coils - nothing changes. In the production of amplifiers, it is enough to compress or push out only a reel of a range of 10 meters, the remaining bands are automatically obtained. Taps on the coils are sealed immediately in the manufacture.

Features of the calculations of the output contour systems

At the moment, on the Internet, there are many Calculators "reading", thanks to which we are able to quickly and relatively accurately calculate the elements of the contour system. The main condition is to enter the program correct data. And here the problems arise. For example: in the program, respected by me, and not only, Igor Goncharenko (DL2KQ), there is a formula for determining the input resistance of the amplifier according to a circuit with a grounded grid. It looks like this: RVX \u003d R1 / S, where S is a steepness of the lamp. This formula is given when the lamp is working on the site of the characteristic with a variable of the steepness, and we have an amplifier with an enthusiastic mesh at an anode current coal of approximately 90 degrees with mesh currents. And so the formula 1 / 0.5S is more suited here. Comparing the empirical formulas of calculations both in our and foreign literature it can be seen that it will mostly look like this: the inlet resistance of the amplifier operating with mesh currents and with a cut-off angle of about 90 degrees R \u003d 1800 / s, R-in ohms.

Example: Take the GK71 lamp, its steepness is about 5, then 1800/5 \u003d 360 ohms. Or gi7b, with a steepness 23, then 1800/23 \u003d 78 ohms.
It would seem what is the problem? After all, the input resistance can be measured, and there is a formula: r \u003d u 2 / 2p. There is a formula, but there is no amplifier yet, it is only designed! It should be added to the above material that the magnitude of the input resistance is frequencies dependent and varies from the input level. Therefore, we have a purely caidious calculation, because at the input circuits we have another element, the equal or cathode choke and its reactants also depends on the frequency and makes its adjustments. In a word, the KSW meter connected to the entrance will display our efforts to coordinate the transceiver with the amplifier.

Practice - Criterion of Truth!

Now about "counting", only already on calculations of VKS (or easier the output p-contour). Here, too, there are nuances given in the "counting" formula of the calculation is also relatively correct. It does not take into account the work of the amplifier (AB 1, B, C), nor the type of the used lamp (triode, tetrod, pentodod) - they have a different KIAN (the utilization utility ratio). You can calculate Ru (resonant resistance) by a classic way.
Calculation for gu81m: UA \u003d 3000V, IA \u003d 0,5A, UC2 \u003d 800B, then the amplitude voltage value on the circuit is equal to (Ucript \u003d UA-US2) 3000-800 \u003d 2200 volts. The anode current in the pulse (Iaimp \u003d Ia * π) will be 0.5 * 3.14 \u003d 1,57a, the current of the first harmonic (I1 \u003d IaimP * iA) will be 1.57 * 0.5 \u003d 0.785a. Then the resonance resistance (Ru \u003d Ucript / i1) will be 2200 / 0.785 \u003d 2802 ohms. Hence the power given to the lamp (PL \u003d I1 * Ucript), will be 0.785 * 2200 \u003d 1727W - this is peak power. The oscillatory power is equal to the product of half the first harmonic of the anode current on the amplitude of the voltage on the circuit (PK \u003d i1 / 2 * Ucript) will be 0.785 / 2 * 2200 \u003d 863.5W, or easier (PK \u003d PL / 2). It is also necessary to subtract losses in the contour system, about 10% and get about 777 watts at the exit.
In this example, we only needed equivalent resistance (RU), and it is 2802 ohms. But it is possible to use empirical formulas: Ru \u003d UA / IA * K (K Take from the table).

Type of lamp	Amplifier work class
Type of lamp
Tetrod	0,574	0,512	0,498
Triodients and pentoders	0,646	0,576	0,56

Therefore, in order to obtain correct data from "counting", it is necessary to introduce the right source data. Using the calculator, often the question arises: what value of loaded quality you want to enter? There are several moments here. If the power of the transmitter is high, and we only have a P-out to "set" harmonics, you have to increase the load quality of the circuit. And this is overestimated contour currents and, therefore, large losses, although there are advantages. With a greater kindness, the shape of the envelope is "more beautiful" and there is no depression and spindles, the transformation coefficient of the P-contour is higher. With a greater loadable thermal rate, the signal is more linear, but losses in such circuit are significant and, therefore, the efficiency is lower. We face a problem somewhat different nature, namely, it is impossible to create a "full-fledged" contour on high-frequency band. There are several reasons - this is a large output capacity of the lamp and a large row. After all, with a large resonant resistance, the optimal calculated data does not fit into reality. It is almost impossible to make such an "ideal" p-circuit (Fig. 1).

Since the calculated value of the "hot" capacitance of the p-contour is not enough, and we have: the output capacity of the lamp (10-30 PF), plus the initial capacity of the capacitor (3-15pf), plus the throttle container (7-12pf), plus the installation capacity ( 3-5 PPF) and in the end "runs out" so much that the normal circuit is not implemented. It is necessary to increase loaded quality, and because of the sharply increased, with the contour currents there are mass problems - increased losses in the circuit, requirements for condensers, switching elements, and to the coil itself, which should be more powerful. To a large extent, these problems can solve the scheme of serial power cascade (Fig. 2).

In which the harmonic filtering factor is higher than that of the P-contour. In the pl-circuit, currents are not large, and therefore losses less.

Placing the coils of the output contour system

As a rule, there are two or three in the amplifier. They should be located perpendicular to each other, so that the mutual induction of the coils was minimal.
Taps to switching elements should be as short as possible. The taps themselves are performed wide, but flexible chinks with the corresponding perimeter as, by the way, the coils themselves. They need to have 1-2 diameters from the walls and screens, especially from the end of the coil. A good example of the rational arrangement of coils are powerful industrial import amplifiers. The walls of the contour system, which are polished and have low resistivity, under the contour system of polished copper sheet. The housing and walls are not heated by the coil, everything is reflected!

Cold setting up the output P-contour

Often, the "Technical Round Table" of Lugansk is given a question: how not having the appropriate instruments "on the cold" set up the output of the reinforcement of the amplifier and choose the taps of the amateur coils?
The method is quite old and is as follows. First, it is necessary to determine the resonant resistance (ROE) of your amplifier. ROE value is taken from the calculations of your amplifier or use the formula described above.

Then you need to connect an impenetrative (or low-inductive) resistor, resistance to ROE and with a capacity of 4-5 watts, between the lamp anode and the overall wire (chassis). The conductors of the connection of this resistor should be as short as possible. Adjusting the output P-circuit is performed when the contour system installed in the enhancer case.

Attention! All power supply voltages must be disabled!

The transceiver output is connected by a short cable segment, with the output of the amplifier. Relay "Bypass" is transferred to the "Transmission" mode. Exhibit the frequency of the transceiver for the middle the desired rangeAt the same time, the internal tuner of the transceiver must be disconnected. Served with a carrier transceiver ("CW" mode) with a capacity of 5 watts.
Manipulating the knobs of the C1 and C2 settings and selecting the inductance of the coil or the removal for the desired amperating radio range achieves the minimum KSW between the transceiver output and the output of the amplifier. The CSW meter can be used built into the transceiver, or connect an external transceiver and amplifier.
The setting is better to start with low-frequency bands, passing to higher frequency.
After setting up the output contour system, do not forget to remove the tuning resistor between the anode and the shared wire (chassis)!

Not all radio amateurs are capable, and financially including, have an amplifier on G78B type lamps, G84B, and even in GU74b. Therefore, we have what we have - as a result, you have to build an amplifier from what is in stock.

I hope that this article will help you in choosing the right circuit solutions in the construction of the amplifier.

Sincerely, Vladimir (UR5MD).

L. Evteeva
"Radio" №2 1981

The output P-circuit of the transmitter requires a thorough setting regardless of whether its parameters obtained by the calculation or it is made as described in the journal. In this case, it is necessary to remember that the purpose of such an operation is not only the actual adjustment of the P-circuit to a given frequency, but also coordination with the output resistance of the terminal cascade of the transmitter and the wave resistance of the feeder line of the antenna.

Some inexperienced radio amateurs believe that it is enough to adjust the contour to a given frequency only by changing the containers of the input and output capacitors of the variable container. But in this way it is not always possible to obtain the optimal coordination of the circuit with the lamp and the antenna.

Proper setting of the P-circuit can only be obtained by the selection optimal parameters All three items.

Customize the P-circuit is convenient in the "cold" state (without connecting power to the transmitter), using its property to transform resistance in any direction. To do this, it is included in parallel in the input of the circuit. Resistor R2 resistance 75 ohms imitates the wave resistance of the feeder line.

The value of load resistance is determined by the formula

ROE \u003d 0.53UPIT / IO

where it is up - the supply voltage of the anode chain of the terminal cascade of the transmitter, B;

Io - the constant component of the anode current of the terminal cascade, A.

Load resistance can be made from Sun resistors. MLT resistors are not recommended to be applied, since at frequencies above 10 MHz in high-resistant resistors of this type there is a noticeable dependence of their resistance from frequency.

The process of the "cold" setting of the P-circuit is as follows. By installing the specified frequency on the generator scale and inserting the capacitance C1 and C2 capacitances to about one third of their maximum values, according to the voltmeter testimony, it is adjusted to the P-contour into a resonance by changing inductance, for example, selecting the removal point on the coil. After that, rotating the handle of the C1 capacitor, and then C2 condenser, you need to achieve further increase in the testimony of the voltmeter and adjust the contour again, changing the inductance. These operations need to be repeated several times.

When approaching K. optimal setting Changes in capacitors of capacitors will be less affected by the voltmeter testimony. When the further change in C1 and C2 tanks will reduce the voltmeter readings, the adjustment of the containers should be stopped and it is possible to more accurately adjust the P-contour into the resonance by changing inductance. On this setting of the P-circuit can be considered complete. The capacitance of the C2 capacitor should be used approximately halfway, which will make it possible to adjust the circuit setting when the real antenna is connected. The fact is that often the antennas performed by descriptions will not be configured for sure. In this case, the conditions of the antenna suspension may differ significantly from the above. In such cases, the resonance will be at a random frequency, the antenna feeder will arise a standing wave, and at the end of the feeder connected to the P-circuit, the reactive component will be present. It is from these considerations that it is necessary to have a margin on adjusting the elements of the P-circuit in the main C2 tank and inductance L1. Therefore, when connecting to the P-contour of the real antenna and an additional adjustment of C2 capacitor and the inductance L1 should be made.

According to the described method, the P-contours of several transmitters worked on various antennas were configured. When using antennas, quite well-tuned in resonance and coordinated with the feeder, the additional adjustment was not required.

We will continue the conversation about the features when constructing a powerful amplifier of the RA with any radio amplifier and those consequences that may be with incorrect installation of the amplifier design. This article provides only the most necessary information that you need to know and take into account during the independent design and manufacture of high power amplifiers. The rest will have to comprehend on your own experience. There is nothing more valuable than your own experience.

Cooling output cascade

Cooling the generator lamp should be sufficient. What is understood by this? Structurally, the lamp is set so that the entire flow of cooling air passes through its radiator. Its volume must correspond to passport data. Most amateur transmitters are operated in the "Reception" mode, so the air volume specified in the passport can be changed in accordance with the work modes.

For example, you can enter three fan speed modes:

maximum for contest work,
medium for everyday and minimal to work with DX.

It is advisable to use low-noise fans. It is appropriate to recall that the fan is turned on simultaneously with the inclusion of the heat voltage or a little earlier, and it turns off at least 5 minutes after its removal. Failure to comply with this requirement reduces the service life of the generator lamp. It is desirable on the way of passing the air flow to install an aero-palt, which through the protection system will turn off all supply voltages in the event of a loss of air flow.

In parallel with the feeding voltage of the fan, it is useful to install a small battery as a buffer that will support the fan operation for a few minutes if the supply network voltage is lost. Therefore, it is better to use a low-voltage DC fan. Otherwise, you will have to resort to an option heard by me on the air from one radio amateur. He, supposedly for blowing the lamp when the power supply is disappeared, keeps a huge inflated camera from the rear wheel of the tractor, connected to the amplifier with an air duct.

Anode chains amplifier

In high power amplifiers, it is advisable to get rid of anodic chokeBy applying a sequential power scheme. Introducing inconveniences with interest will pay off stable and highly efficient work at all amateur Ranges, including a decade. True, in this case, high voltage is the output oscillating circuit and the range switch. therefore variables condensers should be untied from the presence on them high voltageAs shown in Fig.1.

Fig.1.

The presence of anodic choke, if its unsuccessful design, can also cause the above phenomena. As a rule, a competently designed amplifier according to a sequential power circuit does not require the introduction of "antiparaeites" or in the anode, nor in grid circuits. It works steadily on all bands.

The separation capacitors C1 and C3, Fig. 2 should be calculated on the voltage of 2 ... 3 times higher than anodic and sufficient reactive power, which is calculated as a product of high-frequency current passing through the capacitor, to drop the voltage on it. They can be made up of several parallel connected capacitors. In the P-circuit, it is desirable to use a C2 variable capacitor with a minimum initial capacity, with an operating voltage of equally anode. Capacitor C4 should have a gap between plates of at least 0.5 mm.

The oscillating system, as a rule, consists of two coils. One for HF, the other for LF ranges. The coil of the RF range is frameless. It is wound with a copper tube with a diameter of 8 ... 9 mm and has a diameter of 60 ... 70 mm. In order for the tube when the winding is not deformed, fine dry sand is pre-poured into it and the ends are flattened. After winding, cutting off the ends of the tube, the sand is poured. The coil on the NF bands is wound on a frame of or without a copper tube or a thick copper wire with a diameter of 4 ... 5 mm. Its diameter is 80 ... 90 mm. When installing the coil is interconnected.

Knowing inductance, the number of turns for each range can be calculated with high accuracy by the formula:

L (μG) \u003d (0.01dw 2) / (L / D + 0.44)

However, for convenience, this formula can be represented in a more convenient form:

W \u003d c (L (L / D + 0.44)) / 0.01 - D; Where:

W - number of turns;
L - inductance in microgenry;
I - winding length in centimeters;
D - the average diameter of the coil in centimeters.

The diameter and length of the coil is set, based on the design considerations, and the inductance value is selected depending on the load resistance of the lamp used - Table 1.

Table 1.

A variable capacitor C2 on the "hot end" of the P-circuit, Fig. 1 connects not to the lamp anode, but through the removal of 2 ... 2.5 turns. This will reduce the initial capacitance of the circuit on the RF ranges, especially on a 10-meter. Taps from the coil are made by copper strips with a thickness of 0.3 ... 0.5 mm and a width of 8 ... 10 mm. First, they need to be mechanically fixed on the coil, encroaching the strip around the tube, and tighten 3 mm with a screw, illudivation of the connection and removal place. Then the contact location is carefully disappeared.

Attention: When assembling powerful amplifiers, you should not neglect a good mechanical connection and hope only for the soldering. It must be remembered that during operation, all the details are very hot.

In the coils it is impractical to make individual taps for WARC bands. As experience shows, the P-circuit is perfectly tuned in the 24 MHz range in the position of the 28 MHz, 18 MHz in the 21 MHz position, by 10 MHz at a position of 7 MHz, almost without loss of output power.

The switching antenna

To switch antenna in "Reception" mode, a vacuum or ordinary relay designed for the appropriate switching current is used. In order to avoid burning contacts, it is necessary to include an antenna relay on the transmission earlier than the supply of the RF signal, and at the reception a little later. One of the delay circuits is provided in Fig. 2.

Fig.2.

When the amplifier is turned on, the transistor T1 opens. The antenna relay K1 is triggered instantly, and the input relay K2 will work only after the C2 capacitor charge through the R1 resistor. When switching to reception, the switch K2 will turn off instantly, since its winding together with the delay capacitor is blocked by the contacts of the K3 relay through the sparkling resistor R2.

The relay K1 will work with a delay, which depends on the capacitance of the C1 capacitor and the resistance of the relay winding. The T1 transistor is used as a key to reduce the current passing through the controller in the transceiver.

Fig.3.

The capacitance of C1 and C2 capacitors, depending on the reparents used, is selected within 20 ... 100 μF. The presence of a delay of the operation of one relay relative to the other can be easily checked by collecting simple schema With two neon light bulbs. It is known that gas-discharge devices ignition potential above the burning potential.

Knowing this circumstance, contacts relay K1 or K2 (Fig. 3), in the circuit of which neon will light up, will be closed earlier. Another neon will not be able to light up due to reduced potential. Similarly, you can also check the pricing of the relay contacts when switching to the reception by connecting them to the test scheme.

Summarize

When using lamps included according to a circuit with a shared cathode and working without grid currents, such as GU-43B, GU-74B, etc., it is preferably to install a powerful no induction resistor with a capacity of 30 ... 50 W (R4 Figure 4).

First, this resistor will be the optimal load for the transceiver on all bands.
Secondly, it contributes to the solely sustainable work of the amplifier without the use of additional measures.

For full swing from the transceiver, power is required in several, dozens of watts, which will dissipate on this resistor.

Fig.4.

Safety technique

It is notable to recall the safety of safety when working with high power amplifiers. You can not conduct any work or measurements inside the case when the supply voltage is on or, without making sure the filter and blocking capacitors are fully discharged. If with a random hit to the voltage of 1000 ... 1200V there is still a chance to be miracle to be alive, then when exposed to voltage 3000V and above such a chance there is practically no.

Want this or not, but it is necessary to provide for automatic blocking of all feed voltages when the amplifier body is opened. Performing any work with a powerful amplifier, you must always remember that you are working with a device of increased danger!

S. Safonov, (4x1Im)

L. Evteeva
"Radio" №2 1981

Proper setting of the P-circuit can be obtained only by selecting the optimal parameters of all three items.

The value of load resistance is determined by the formula

ROE \u003d 0.53UPIT / IO

where it is up - the supply voltage of the anode chain of the terminal cascade of the transmitter, B;

Io - the constant component of the anode current of the terminal cascade, A.

When approaching the optimal setting of changes in the capacitors of capacitors will be all to a lesser extent to the voltmeter readings. When the further change in C1 and C2 tanks will reduce the voltmeter readings, the adjustment of the containers should be stopped and it is possible to more accurately adjust the P-contour into the resonance by changing inductance. On this setting of the P-circuit can be considered complete. The capacitance of the C2 capacitor should be used approximately halfway, which will make it possible to adjust the circuit setting when the real antenna is connected. The fact is that often the antennas performed by descriptions will not be configured for sure. In this case, the conditions of the antenna suspension may differ significantly from the above. In such cases, the resonance will be at a random frequency, the antenna feeder will arise a standing wave, and at the end of the feeder connected to the P-circuit, the reactive component will be present. It is from these considerations that it is necessary to have a margin on adjusting the elements of the P-circuit in the main C2 tank and inductance L1. Therefore, when connecting to the P-contour of the real antenna and an additional adjustment of C2 capacitor and the inductance L1 should be made.

Transcript.

1 392032, G. Tambov Aglodin G. A. P Contour Features of modern semiconductor technologies of the victorious procession of modern semiconductor technologies and integrated circuits The lamp high-frequency power amplifiers did not lose their relevance. Lamp power amplifiers, as well as power amplifiers on transistors inherent their advantages and disadvantages. But the indisputable advantage of the lamp power amplifiers is the work on the incidental load without failover of electrical accumulating devices and without equipping the power amplifier with special protection chains from mismatch. An integral part of anyone lamp amplifier Power is an aode n outline Rice1. In the work of R, the method of calculating the transmitter contour Konstantin Aleksandrovich Shulgin gave a very detailed and mathematically accurate analysis of the contour. Fig.1 to save the reader from the search for the necessary journals (all the same more than 20 years have passed), the formulas for calculating the contour of the borrowed from: FO \u003d F n f to (1) are the average meter frequency of the HC range; Qn x r \u003d loaded good quality n contour; The own quality of the contour is mainly determined by the quality of the inductive element and is within the limits (in some sources is indicated as Q XX); Own losses in the circuit, mainly in the inductance coil, the exact calculations are not served, as it is necessary to consider the skin effect and the loss of radiation on the field. This formula has an error of ± 20%; N \u003d (2) The coefficient of transformation n contour; equivalent impedance of the anode chain of the power amplifier; load resistance (feeder line resistance, antenna input resistance, etc.); Qn η \u003d 1 (3) kpd n contour;

2 x \u003d n η η (qn η) n 1 qn (4); X x \u003d qn x η (5); Qn x x \u003d (6); η 2 2 (+ x) 2 10 \u003d x 10 \u003d 6 12 PF (7); X μg (9); 10 \u003d 12 PF (8); X n circuit on one side is a resonant chain with QN quality rate, on the other hand, a resistance transformer that converts the low-voltage load resistance into high-level equivalent impedance of an anode chain. Consider the possibility of transforming using a n circuit of various load resistance values \u200b\u200binto the equivalent impedance of the anode chain, provided \u003d const. Suppose it is necessary to implement the contour for the power amplifier assembled on four pentodies of the GU-50 included in parallel according to the scheme with a shared grid. The equivalent resistance of the anode chain of such an amplifier will be \u003d 1350 (for each penter 5400 ± 200 ohms), output power It will be approximately a W, the power consumed from the power supply of the POT W Pot. By specified conditions: range of 80 meters, fo \u003d ff \u003d \u003d, n \u003d 1350Ω, qn \u003d 12, \u003d 200 by formulas (1) (9) we will calculate for five values: \u003d 10 ohms, \u003d 20 ohms, \u003d 50 ohm, \u003d 125 Ohm, \u003d 250 ohms. The results of the calculation are shown in Table 1. Table 1 Range of 80 meters, FO \u003d Hz, \u003d 1350Ω, QN \u003d 12, \u003d 200 KSV N PF MKGN PF, 78 5.7 20 2.5,67,557,97 5,8 50 1.0 27.0 333.04 6.5 10.8 302.98 7.94 972.4 273.80 9.56 642.2 Similar calculations must be made to other ranges. More clearly change the values \u200b\u200bof the elements, and from the load resistance is given in the form of graphs as a function from Fig. 2.

3 400 C1 PF μg 8.8 7.2 5, PF Fig. 2 We note the characteristic features of the graphs: the value of the C1 container monotonously decreases, the inductance value monotonically increases, but the value of the C2 capacity has a maximum of \u003d 16 20 ohms. It is necessary to pay special attention to this and take into account when choosing a C2 tank restructuring range. Moreover, the load resistance is purely active character possesses quite rarely, as a rule, the load resistance (antenna) has a comprehensive nature and to compensate for the reactive component, an additional stock is necessary for the rope of adjustment of the elements of the contour. But more correctly use the SAU block (matching antenna device) or an antenna tuner. Sau is desirable to use both lamp transmitters for transistor transmitters SAU be sure. Based on the above, we conclude that for coordination with the change in the load resistance, it is necessary to restructure all three elements n circuit Fig.3. Fig. 3. Practical implementation The contour from the mid-60s of the last century walks the scheme of the contours of Fig.4, which seemed to take root and does not cause special suspicion. But let's pay attention to the switching method of the inductive element in the n circuit. 1 2 s Fig.4 T Fig.5 s Who tried to switch the transformer or autotransformer in Similarly, Fig.5. Even one short-circuited turn can lead to a complete failure of the entire transformer. And with the coil of inductance in the circuit, we do without a shade of doubt exactly the same!?

4 First, the magnetic field of the non-closed part of the inductance coil creates a current short circuit I kz in a closed part of the coil Fig.6. For reference: the amplitude of the current in the circuit (and in any other resonant system) has a not so small value: i to 1 a1 \u003d \u003d i qn \u003d 0.8a, where: I K1 amplitude of the resonant current in n circuit; I A1 amplitude of the first harmonic of anodic current (for four GU-50 I A1 0,65a) Fig.6 and where the short circuit current will be consumed (I kz Fig.6): to heat the short-circuited turns themselves and to heat the contact nodes of the switch s (Fig.4). Q-meter Fig. 7 Q-meter Q \u003d 200 Q KZ 20 A) b) Secondly, if it is possible to use the Q-meter (Q-Meter) to remove the testimony from an open inductor coil and with partially closed turns of Fig. 7a, Fig. 7b Q OKS will be less than q, now by formula (3) we define the efficiency of the circuit: Qn 12 η \u003d 1 \u003d 1 \u003d 0.94, 200 qn 12 η kz \u003d 1 \u003d 1 \u003d 0.4?! KZ 20 at the outlet of the contour We have 40% of the power, 60% left for heating, vortex currents, etc. The generalization of the first and second in the end we get no contour, but some kind of HF crucible. I kz What are the ways of constructive improvement n circuit: Option1 The scheme in fig.4 can be upgraded as follows: the number of inductive elements should be equal to the number of ranges, and not two, three coils as usual. To reduce the magnetic interaction near the arranged coils of their axis, it is necessary to have perpendicular to each other, at least in space there are three degrees of freedom, the coordinates x, y, z. Switching in places of connection of individual coils. Option2 Use tunable inductive elements, such as variometers. Variometers will allow more subtly to configure the contour (Table 1 and Fig.3). Option3 Use this type of switching that eliminated the presence of closed or partially closed coils. One of possible options Switching schemes are shown in Fig.8.

5 m m m Fig. 8 Literature 1. Shulgin K. A. Methods of calculation of radio transmitter circuit Radio, 7

3.5. A complex parallel oscillating circuit I of the contour, in which at least one parallel branch contains the reactivity of both signs. I C C i I magnetic connection between and no. The condition of resonance

Antenna-matching device Performed: student c. FRM-602-0 Purpose: Development of an automatic control scheme for a tracking self-tower to a given CBW task: 1) study the device and principles

0. Measurement of pulse signals. The need to measure pulse signals parameters occurs when it is required to obtain a visual signal estimate in the form of oscillograms or measuring instrumentation readings,

Lecture Theme Opt Systems Allocation of the beneficial signal from a mixture of various side signals and noise is carried out by frequency-selective linear chains that are built on the basis of oscillatory

The method of integrated amplitudes Harmonic voltage fluctuations on the clips of elements R or causes the flow of harmonic current of the same frequency. Differentiation Integration and Addition of Functions

Practical tasks for the exam in the discipline "Radio engineering chains and signals" 1. Free oscillations in the perfect circuit have a voltage amplitude of 20V, the amplitude of the current 40mA and the wavelength is 100m. Determine

RU9AJ "KV and VHF" 5 2001. Power amplifier on GU-46 lamps in shortwaves is becoming increasingly popular glass pentodent GU-46, on which RU9AJ built powerful amplifier All amateur

The invention relates to electrical engineering and is intended for the implementation of powerful, cheap and efficient adjustable transistor high-frequency resonant voltage converters of various applications,

Ministry of Education and Science of the Russian Federation Kazan National Research Technical University (book-kai). A. N. Tupoleva Department of Radio Electronic and Quantum Devices (RECU) Methodical Instructions

Practical classes in CHP. Task list. occupation. Calculation of equivalent resistance and other relations .. For chain A C D F, find equivalent resistances between clips a and, c and d, d and f, if \u003d

33. Resonance phenomena in a sequential oscillatory circuit. The purpose of the work: experimentally and theoretically investigate resonant phenomena in a sequential oscillatory circuit. Required equipment:

Moscow state University them. MV Lomonosov Faculty of Faculty of Department of General Physics La B O R A T O R N S P R A C T I K U M P O O B S Y F S EY F S I C E (Electricity and Magnetism) Laboratory

Lecture 8 Topic 8 Special amplifiers Permanent current amplifiers A DC amplifiers (POP) or amplifiers of slowly changing signals are called amplifiers that are able to strengthen electrical

03090. Linear chains With inductively connected coils. Objective: Theoretical and experimental studies of a circuit with mutual inductance, determination of the mutual inductance of two connected magnetic

Laboratory work 3 Study of forced oscillations in the oscillatory loan The goal of the work: study the dependence of the current force in the oscillatory circuit from the frequency source of EMS.included in the outline and measurement

Russian Federation (19) RU (11) (51) MPK H03B 5/12 (2006.01) 173 338 (13) U1 RU 1 7 3 3 3 8 U 1 Federal Intellectual Property Service (12) Description of the useful model to patent (21 ) (22)

Laboratory work "Bridge measurements" The measuring bridge with a measuring bridge is called an electrical device for measuring resistance, containers, inductances and other electrical quantities. Bridge

The reactive power compensation device in the electrical chain The invention relates to the field of electrical engineering and intended for use in industrial electrical networks of enterprises to compensate

Laboratory work 6 Study of self-induction. The goal of the work is: to investigate the peculiarities of self-induction, measure the inductance of the coil and EMF of self-induction. Equipment: Coil 3600 turns R l »50

Lecture 7 Topic: Special amplifiers 1.1 Power amplifiers (output cascades) Power enhancement cascades are usually output (terminal) cascades to which the external load is connected, and are intended

Laboratory work 5. Electrical chains With mutual inductance 1. Task on work 1.1. When preparing for work, explore: ,. 1.2. Study chains with inductively connected

Laboratory work 16 transformer. Objective: Explore the operation of the transformer in idle mode and under load. Equipment: transformer (collect a scheme for a lowering transformer!), Source

Page 1 of 8 6p3c (Output Rade Tetrod) The main dimensions of the lamp 6p3c. General data Radie Tetrod 6Fz is designed to enhance low power. Applied in the weekend one-stroke and two-stroke

Measurement of the parameters of the magnetic pipelines with a resonant method. The resonance measurement method can be recommended for use in the home laboratory along with the ammeter voltmeter method. It is distinguished

Contents of the academic discipline List and content of sections (modules) of the discipline p / p Module discipline lectures, h \\ correspondence 1 Introduction 0.25 2 Linear DC electric circuits 0.5 3 Linear electrical

5.3. Comprehensive resistance and conductivity. Comprehensive impedance chain resistance: x Ohm law in complex form: I U u u e e e e e i i u i u module is equal to the ratio of voltage amplitudes and current A

An option 708 in the electrical circuit is the source of the sinusoidal EFS E (ωt) sin (ωt ψ). Chain diagram shown in rice .. The active value of the EFS E source, the initial phase and the value of the parameters of the chain

Download the instruction manual for the radio station R 140m \u003e\u003e\u003e Download the instruction manual for the radio station R 140m download the instruction manual for the radio station R 140m contours are interconnected through

Resonance "On Palm". The resonance is the regime of a passive two-pole containing inductive and capacitive elements in which its reactive resistance is zero. The condition for the emergence of resonance

G. Thr. (EW3LB) "KV and VHF" 7-96 Something about RA on most amateur radio stations is applied structural scheme: Low power transceiver plus ra. RA happen different: GU-50х2 (x3), Mr. 811x4, GU-80х2B, GU-43BX2

Condenser oscillatory circuit for a long time connected to the source constant voltage (See Figure). At the time T \u003d 0, the switch to translate from position 1 to position 2. Graphs A and B represent

Laboratory work 1 Study of DC energy transmission from an active two-pole in the load The goal of the work: learn how to determine the parameters of the active two-pole different ways: via

PGUPS Laboratory work 21 "Investigation of an inductive coil without a core" performed Kruglov V.A. Checked Kostrominov A.A. St. Petersburg 2009 Table of Contents ... 1 List of Conditional Designations: ...

Examination Examination is one of the forms of independent learning activities of students on the use and deepening of knowledge and skills obtained on lecture, laboratory and practical

Calculation of the output transformer of the resistance of the DMW-range transmitter Alexander Titov Home address: 634050, Russia, Tomsk, Lenin Ave., 46, apt. 28. Tel. 51-65-05, e-mail: [Email Protected] (Circuitry.

Test for electrical engineering. Option 1. 1.Wext devices are shown in the diagram? a) light bulb and resistor; b) the light bulb and fuse; c) electric current source and resistor.

5.12. Integral AC amplifiers Low frequency amplifiers. UHC In the integral execution, this is usually aperiodic amplifiers covered by the general (on constant and variable current)

Broadband transformers 50-ohm blocks have a chain with resistance, often significantly differ from 50 ohms and lying in the range of 1-500 ohms. In addition, it is necessary that the input / output of the 50th one

Examples possible schemes Solving the tasks of the semester task task. Methods for calculating linear electrical circuits. The task. Determine the current flowing into the diagonal of the unbalanced Whitstone bridge

Laboratory work 4 Electric oscillating circuit The purpose of the work is to study the theory of resonant radiotechnical chains of oscillatory contours (serial and parallel). Explore ACH and FCH

050101. Single-phase transformer. Objective: Get acquainted with the device, the principle of operation of a single-phase transformer. Remove its main characteristics. Required Equipment: Modular Training Complex

Laboratory work Amplitude modulator Operation: Investigate a method for producing an amplitude-modulated signal using a semiconductor diode. High-frequency fluctuations amplitude

Laboratory work 6 Study of the headerodine fee of a professional receiver Objective: 1. Get acquainted with concept scheme and a constructive solution of the heteroodine fee. 2. Remove the main characteristics

Ministry of Education and Science of the Russian Federation Kazan National Research Technical University. A.N.Tuolev (book-kai) Department of Radio Electronic and Quantum Devices (RECU) Methodical instructions

The sinusoidal current "on the palm" Most of the electrical energy is produced in the form of EMF, varying in time by the law of harmonic (sinusoidal) function. Sources of harmonic EMF serve

03001. Elements of electrical circuits of sinusoidal current The goal of the work: familiarize yourself with the main elements of the electrical circuits of the sinusoidal current. Master the methods of electrical measurements in the chains of sinusoidal

Methods for turning the transistor into the enhanced cascade scheme As indicated in Section 6, an amplifying cascade can be represented by a 4-pin to the input clamp of which the signal source is connected

State Educational Institution of secondary vocational education "Novokuznetsk Food Industry Technical School" Working Program of Educational Discipline Electrical Equipment and Electronic Technology

Electromagnetic oscillations Quasistationary currents Processes in a oscillatory circuit The oscillating circuit The circuit consisting of the included sequential coil of inductance, capacitor capacitance with and resistor

Laboratory work on theoretical basics of electrical engineering Table of contents: the procedure for performing and designing laboratory works ... 2 Measuring instruments for laboratory work ... 2 Work 1. Laws

Mordovian State University named after N.P. Harev Institute of Physics and Chemistry Department of Radio Engineering Bardin V.M. Radio devices Power amplifiers and terminal terminal terminals. Saransk,

11. Theorem on the equivalent source. A is an active two-pole, the outer chain between parts A and there is no magnetic communication. A I A U U XX A I CW 1. The theorem on the equivalent voltage source (TEVENINE Theorem):

Coils and transformers with steel cores Basic provisions and ratios. The chain with steel is an electrical chain, the magnetic stream of which is completely or partially concluded in one

58 A. A. Titov UDC 621.375.026 A. A. Titov Protection of strip power amplifiers from overload and modulation of amplitude of powerful signals It is shown that the bipolar transistor is a controlled limiter

Part 1. Linear DC circuits. Calculation of the DC electrical circuit with the coagulation method (equivalent replacement method) 1. Theoretical questions 1.1.1 Give definitions and explain the differences:

3.4. Electromagnetic oscillations Basic laws and formulas Own electromagnetic oscillations occur in an electrical circuit, which is called a oscillating circuit. Closed oscillating contour

Preface Chapter 1. DC circuits 1.1.Electric chain 1.2. Electric current 1.3.Son resistance and conductivity 1.4.Electric voltage. Ohm's law 1.5.Svyaz between EMF and the voltage of the source.

Page 1 of 8 Automatic antenna tuner of the branded transceiver completely refuses to agree on the entrance of the old good PA on a lamp with a common grid. But the old homemade apparatus was agreed and

Topic 11 Radio receivers Radio receivers are intended for receiving information transmitted by means of electromagnetic waves and transforming it to the form in which it can be used.

The list of the items of the Item "Electrical Equipment" 1. Electric DC circuits. 2. Electromagnetism. 3. Electrical circuits of alternating current. 4. Transformers. five. Electronic devices and appliances.

(B.1) Test questions on "Electronics". Part 1 1. The first Kirchoff law establishes the relationship between: 1. voltage drops on elements in a closed circuit; 2. currents in the circuit node; 3. Power dissipation

Laboratory work 6 Research of the air transformer. Task to work .. In preparation for work, study:, ... Construction of the air transformer substitution scheme..3.

Laboratory work 14 Antenna Objective: Studying the principle of operation of the receiving-transmitting antenna, constructing a focus chart. Antenna parameters. Antennas are used to convert current energy high

Work 1.3. Studying the phenomenon of mutual induction The purpose of the work: the study of the phenomena of mutual induction of two coaxially located coils. Instruments and equipment: power supply; electronic oscilloscope;

\\ Home \\ R.L. Constructions \\ Power amplifiers \\ ... Power amplifier on gu-81m based on the mind from P-140 brief specifications Amplifier: UANODA .. +3200 V; UC2 .. +950 V; UC1-300 B (Tx), -380 V (Rx);

Moscow Aviation Institute (National Research University) "MAI" Department of Theoretical Radio Engineering Laboratory work "Investigation of first-order chains" is approved

Ministry of Education of the Russian Federation State Educational Institution of Higher Professional Education - "Orenburg State University" College of Electronics and Business

Laboratory work 1 Study of the broadband transformer of the objective of operation: 1. Investigation of the operation of the transformer in the frequency range in harmonic and impulse effects. 2. Study of basic

Production of a transmitter by 2.8 3,3 MHz with amplitude modulation to a protective grid. For the routing of the three GU 50 lamps into the control grid, it is necessary from 50 to 100V voltage, power not more than 1 W. And for

Theme 9 .. characteristics, start and reverse asynchronous engines. Single-phase asynchronous motors. Questions theme .. Asynchronous motor with phase rotor .. Performance characteristics asynchronous engine. 3.

1 variant A1. In the equation of harmonic oscillation q \u003d qmcos (ωt + φ0), the magnitude standing under the sign of the cosine is called 3) the amplitude of the charging A2. The figure shows a graph of the current force in the metal

The location of the discipline in the structure of the educational program of the discipline "Basics of electrical engineering and electronics" is the discipline of the base part. Working programm compiled in accordance with the requirements of the federal