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Quick study of electrical and electronics engineering. Home appliance repair lessons on video

Hello my dear friends! In this blog I want to tell all beginning radio amateurs about where to start this difficult path. I was prompted to write this article by people who appear on forums and create topics there with such loud names as “help me distinguish a resistor from a capacitor in a circuit” and “Give me some circuits, I don’t know anything.” Despite the fact that people don’t know anything and don’t want to study anything or use their brains... Perhaps this article may seem boring to you, but don’t worry - here you will learn a lot of new things

1. You need to decide - why do you need it?

This point is very important - why do you need it? Why do you need radio equipment?
Radio technology is a complex thing, and if you treat it “freebie”, then it may not forgive you for this freebie!
Do not think that I am simply and unreasonably scaring you - believe me, there have been very accidents. I won’t talk about them here - if you want, look on the Internet.
So first of all, you have to remember: Safety precautions and accuracy should be your first priority!

2. Basic concepts and knowledge of physics.

In order to start the journey, you need to acquire a basic knowledge base, namely, a school excursion about electronics in a physics course. From it you should learn one main law that regulates processes in electrical engineering, so to speak, “the entire electrical network”: Ohm’s Law - I=U/R. This is the basis!!! Knowing it, you will begin to understand electronics! In fact, besides this law, you need to learn absolutely everything from there, because physics is the queen of technical sciences!

3. Theory.

Practice is impossible without theory!!! If you start soldering without any knowledge, you doom your device to a non-working state!
I will give several books that, in my opinion, are excellent for studying radio engineering:
1. Borisov V.G. Young radio amateur- download from Padabum
This book is the beginning. This book may seem old to you, but don't worry, you will need to learn all the theoretical parts in this book. It is presented there in an interesting form, so you won’t be bored
2. Revich Yu.V. - Entertaining electronics- download from Yandex.Disk
This book provides a short course in electronics - from Ohm's law to microcontrollers. Very interesting book!!! You can start with it.
If you want to learn electronics from beginning to end, study the great classic - Horowitz P., Hill W. The Art of Circuit Design in three volumes - download from Padabum volume 1, volume 2, volume 3.
This is the greatest manual on electronics!!!
In addition to these books, you can find a huge amount of information on our website in the section.

4. Practice.

Whatever one may say, theory is impossible without practice. Look for diagrams, study them, and you will succeed!!!
The "Radio Circuits" site you are currently on is full of circuits to repeat. And the section is full of very easy schemes. Be sure to be patient, don’t give up halfway - and everything will be fine!

Finally, I want to say one very important thing - follow safety precautions!!!
I was with you Antracen. Good luck!

Each of us, when we begin to get involved in something new, immediately rushes into the “abyss of passion”, trying to complete or implement difficult projects homemade. This happened to me when I became interested in electronics. But as usually happens, the first failures diminished the passion. However, I was not used to retreating and began to systematically (literally from the beginning) comprehend the mysteries of the world of electronics. And so the “guide for beginner techies” was born.

Step 1: Voltage, Current, Resistance

These concepts are fundamental and without familiarity with them, continuing to teach the basics would be pointless. Let's just remember that every material is made up of atoms, and each atom in turn has three types of particles. An electron is one of these particles that has a negative charge. Protons have a positive charge. Conducting materials (silver, copper, gold, aluminum, etc.) have many free electrons that move randomly. Voltage is the force that causes electrons to move in a certain direction. A flow of electrons that moves in one direction is called a current. When electrons move through a conductor, they encounter some kind of friction. This friction is called resistance. The resistance “squeezes” the free movement of electrons, thus reducing the amount of current.

A more scientific definition of current is the rate of change in the number of electrons in a certain direction. The unit of current is Ampere (I). In electronic circuits, the current flowing is in the milliamp range (1 ampere = 1000 milliamps). For example, the typical current for an LED is 20mA.

The unit of measurement for voltage is Volt (V). The battery is a source of voltage. Voltages of 3V, 3.3V, 3.7V and 5V are the most common in electronic circuits and devices.

Voltage is the cause and current is the result.

The unit of resistance is Ohm (Ω).

Step 2: Power Supply

The battery is a voltage source or “proper” source of electricity. The battery produces electricity through an internal chemical reaction. It has two terminals on the outside. One of them is the positive terminal (+ V), and the other is the negative terminal (-V), or “ground”. Typically there are two types of power supplies.

  • Batteries;
  • Batteries.

Batteries are used once and then disposed of. Batteries can be used several times. Batteries come in many shapes and sizes, from miniature ones used to power hearing aids and wristwatches to room-sized batteries that provide backup power for telephone exchanges and computer centers. Depending on the internal composition, power supplies can be of different types. A few of the most common types used in robotics and engineering projects are:

Batteries 1.5 V

Batteries with this voltage can come in different sizes. The most common sizes are AA and AAA. Capacity range from 500 to 3000 mAh.

3V lithium coin

All of these lithium cells are rated at 3V nominal (on load) and with an open circuit voltage of around 3.6V. The capacity can reach from 30 to 500 mAh. Widely used in handheld devices due to their tiny size.

Nickel metal hydride (NiMH)

These batteries have high energy density and can charge almost instantly. Another important feature is the price. Such batteries are cheap (compared to their size and capacity). This type of battery is often used in robotics homemade products.

3.7V lithium-ion and lithium-polymer batteries

They have good discharge capacity, high energy density, excellent performance and small size. Lithium polymer battery is widely used in robotics.

9 volt battery

The most common shape is a rectangular prism with rounded edges and terminals located on top. The capacity is about 600 mAh.

Lead-acid

Lead-acid batteries are the workhorse of the entire electronics industry. They are incredibly cheap, rechargeable and easy to buy. Lead-acid batteries are used in mechanical engineering, UPS (uninterruptible power supplies), robotics and other systems where a large supply of energy is needed and weight is not so important. The most common voltages are 2V, 6V, 12V and 24V.

Series-parallel connection of batteries

The power supply can be connected in series or parallel. When connected in series, the voltage increases, and when connected in parallel, the current value increases.

There are two important points regarding batteries:

Capacity is a measure (usually in Amp-h) of charge stored in a battery and is determined by the mass of active material contained in it. Capacity represents the maximum amount of energy that can be extracted under certain specified conditions. However, the actual energy storage capacity of a battery may vary significantly from the nominal stated value, and battery capacity is highly dependent on age and temperature, charging or discharging conditions.

Battery capacity is measured in watt-hours (Wh), kilowatt-hours (kWh), ampere-hours (Ah) or milliamp-hours (mAh). A watt-hour is the voltage (V) multiplied by the current (I) (we get power - the unit of measurement is Watts (W)) that a battery can produce for a certain period of time (usually 1 hour). Since the voltage is fixed and depends on the type of battery (alkaline, lithium, lead-acid, etc.), often only Ah or mAh is marked on the outer shell (1000 mAh = 1Ah). For longer operation of an electronic device, it is necessary to take batteries with low leakage current. To determine battery life, divide the capacity by the actual load current. A circuit that draws 10 mA and is powered by a 9-volt battery will run for about 50 hours: 500 mAh / 10 mA = 50 hours.

With many types of batteries, you cannot "drain" the energy completely (in other words, the battery cannot be completely discharged) without causing serious, and often irreparable, damage to the chemical constituents. The depth of discharge (DOD) of a battery determines the fraction of current that can be drawn. For example, if DOD is defined by the manufacturer as 25%, then only 25% of the battery capacity can be used.

Charging/discharging rates affect the nominal battery capacity. If the power supply discharges very quickly (ie, the discharge current is high), then the amount of energy that can be extracted from the battery is reduced and the capacity will be lower. On the other hand, if the battery is discharged very slowly (low current is used), then the capacity will be higher.

Battery temperature will also affect capacity. At higher temperatures, battery capacity is generally higher than at lower temperatures. However, deliberately increasing the temperature is not an effective way to increase battery capacity, as it also reduces the life of the power supply itself.

C-Capacity: The charge and discharge currents of any battery are measured relative to its capacity. Most batteries, with the exception of lead acid, are rated at 1C. For example, a battery with a capacity of 1000mAh produces 1000mA for one hour if the level is 1C. The same battery, at 0.5C, produces 500mA for two hours. With a 2C level, the same battery produces 2000mA for 30 minutes. 1C is often referred to as the one-hour discharge; 0.5C is like a two-hour clock and 0.1C is like a 10-hour clock.

Battery capacity is usually measured using an analyzer. Current analyzers display information as a percentage based on the rated capacity value. A new battery sometimes produces more than 100% current. In this case, the battery is simply rated conservatively and can last longer than what the manufacturer specifies.

The charger can be selected in terms of battery capacity or C value. For example, a charger rated C/10 will fully charge the battery in 10 hours, a charger rated 4C would charge the battery in 15 minutes. Very fast charging rates (1 hour or less) usually require the charger to carefully monitor battery parameters, such as voltage limits and temperature, to prevent overcharging and damage to the battery.

The voltage of a galvanic cell is determined by the chemical reactions that take place inside it. For example, alkaline cells are 1.5 V, all lead acid cells are 2 V, and lithium cells are 3 V. Batteries can be made up of multiple cells, so you will rarely see a 2 V lead acid battery. They are typically wired together internally to provide 6V, 12V, or 24V. Keep in mind that the nominal voltage of a "1.5V" AA battery actually starts at 1.6V, then quickly drops to 1.5, then slowly drifts down to 1.0 V, at which point the battery is considered 'discharged'.

How to choose the best battery for crafts?

As you already understand, there are many types of batteries with different chemical compositions available in the public domain, so it is not easy to choose which power is best for your particular project. If the project is very energy dependent (large sound systems and motorized homemade products) should choose a lead-acid battery. If you want to build a portable under the tree, which will consume little current, then you should choose a lithium battery. For any portable project (light weight and moderate power supply), choose a lithium-ion battery. You can choose a cheaper nickel metal hydride (NIMH) battery, although they are heavier, but are not inferior to lithium-ion in other characteristics. If you would like to do a power-hungry project, a lithium-ion alkaline (LiPo) battery would be the best option because it is small in size, lightweight compared to other types of batteries, recharges very quickly and delivers high current.

Do you want your batteries to last a long time? Use a high quality charger that has sensors to maintain proper charge levels and low current charging. A cheap charger will kill your batteries.

Step 3: Resistors

A resistor is a very simple and most common element in circuits. It is used to control or limit current in an electrical circuit.

Resistors are passive components that only consume energy (and cannot produce it). Resistors are typically added to a circuit where they complement active components such as op-amps, microcontrollers, and other integrated circuits. They are typically used to limit current, separate voltages, and separate I/O lines.

The resistance of a resistor is measured in Ohms. Larger values ​​can be associated with the kilo-, mega-, or giga prefix to make the values ​​easy to read. You can often see resistors labeled kOhm and MOhm range (mOhm resistors are much less common). For example, a 4,700Ω resistor is equivalent to a 4.7kΩ resistor and a 5,600,000Ω resistor can be written as 5,600kΩ or (more commonly) 5.6MΩ.

There are thousands of different types of resistors and many companies that make them. If we take a rough gradation, there are two types of resistors:

  • with clearly defined characteristics;
  • general purpose, whose characteristics may “walk” (the manufacturer himself indicates the possible deviation).

Example of general characteristics:

  • Temperature coefficient;
  • Voltage factor;
  • Frequency range;
  • Power;
  • Physical size.

According to their properties, resistors can be classified as:

Linear resistor- a type of resistor whose resistance remains constant with increasing potential difference (voltage) that is applied to it (the resistance and current that passes through the resistor does not change with the applied voltage). Features of the current-voltage characteristic of such a resistor are a straight line.

Non linear resistor is a resistor whose resistance changes depending on the value of the applied voltage or the current flowing through it. This type has a non-linear current-voltage characteristic and does not strictly follow Ohm's law.

There are several types of nonlinear resistors:

  • NTC (Negative Temperature Coefficient) resistors - their resistance decreases with increasing temperature.
  • PEC (Positive Temperature Coefficient) resistors - their resistance increases with increasing temperature.
  • LZR resistors (Light-dependent resistors) - their resistance changes with changes in the intensity of the light flux.
  • VDR resistors (Voltage Dependent Resistors) - their resistance critically decreases when the voltage value exceeds a certain value.

Non-linear resistors are used in various projects. LZR is used as a sensor in various robotics projects.

In addition, resistors come with a constant and variable value:

Fixed resistors- types of resistors whose value is already set during production and cannot be changed during use.

Variable resistor or potentiometer – a type of resistor whose value can be changed during use. This type usually has a shaft that is turned or moved manually to change the resistance value over a fixed range, e.g. 0 kOhm to 100 kOhm.

Resistance Store:

This type of resistor consists of a "package" that contains two or more resistors. It has several terminals through which the resistance value can be selected.

The composition of resistors is:

Carbon:

The core of such resistors is cast from carbon and a binder, creating the required resistance. The core has cup-shaped contacts that hold the resistor rod on each side. The entire core is filled with a material (like Bakelite) in an insulated casing. The housing has a porous structure, so carbon composite resistors are sensitive to relative ambient humidity.

These types of resistors usually produce noise in the circuit due to the electrons passing through the carbon particles, so these resistors are not used in "important" circuits, although they are cheaper.

Carbon deposition:

A resistor that is made by depositing a thin layer of carbon around a ceramic rod is called a carbon deposited resistor. It is made by heating ceramic rods inside a flask of methane and depositing carbon around them. The value of the resistor is determined by the amount of carbon deposited around the ceramic rod.

Film resistor:

The resistor is made by depositing sprayed metal in a vacuum onto a ceramic rod base. These types of resistors are very reliable, have high stability and also have a high temperature coefficient. Although they are expensive compared to others, they are used in basic systems.

Wirewound resistor:

A wirewound resistor is made by winding metal wire around a ceramic core. The metal wire is an alloy of various metals selected according to the stated features and resistance of the required resistor. This type of resistor has high stability and can also handle high power, but they are generally bulkier than other types of resistors.

Metal-ceramic:

These resistors are made by baking some metals mixed with ceramics on a ceramic substrate. The proportion of the mixture in a mixed metal-ceramic resistor determines the resistance value. This type is very stable and also has precisely measured resistance. They are mainly used for surface mounting on printed circuit boards.

Precision resistors:

Resistors whose resistance value lies within a tolerance, so they are very accurate (the nominal value is in a narrow range).

All resistors have a tolerance, which is given as a percentage. The tolerance tells us how close to the nominal value the resistance can vary. For example, a 500Ω resistor that has a tolerance value of 10% could have a resistance between 550Ω or 450Ω. If the resistor has a 1% tolerance, the resistance will only change by 1%. So a 500Ω resistor can vary from 495Ω to 505Ω.

A precision resistor is a resistor that has a tolerance level of only 0.005%.

Fusible resistor:

The wirewound resistor is designed to burn out easily when the rated power exceeds the limiting threshold. Thus the fusible resistor has two functions. When the supply is not exceeded, it serves as a current limiter. When the rated power is exceeded, the oa functions as a fuse; once blown, the circuit becomes open, which protects the components from short circuits.

Thermistors:

A heat-sensitive resistor whose resistance value changes with operating temperature.

Thermistors display either positive temperature coefficient (PTC) or negative temperature coefficient (NTC).

How much resistance changes with changes in operating temperature depends on the size and design of the thermistor. It is always better to check the reference data to know all the specifications of the thermistors.

Photoresistors:

Resistors whose resistance changes depending on the light flux that falls on its surface. In a dark environment, the resistance of the photoresistor is very high, several M Ω. When intense light hits the surface, the resistance of the photoresistor drops significantly.

Thus, photoresistors are variable resistors, the resistance of which depends on the amount of light that falls on its surface.

Leaded and leadless types of resistors:

Terminal Resistors: This type of resistor was used in the earliest electronic circuits. The components were connected to the output terminals. Over time, printed circuit boards began to be used, into the mounting holes of which the leads of radio elements were soldered.

Surface Mount Resistors:

This type of resistor has become increasingly used since the introduction of surface mount technology. Typically this type of resistor is created by using thin film technology.

Step 4: Standard or Common Resistor Values

The designation system has origins that go back to the beginning of the last century, when most resistors were carbon with relatively poor manufacturing tolerances. The explanation is quite simple - using a 10% tolerance you can reduce the number of resistors produced. It would be ineffective to produce 105 ohm resistors, since 105 is within the 10% tolerance range of a 100 ohm resistor. The next market category is 120 ohms because a 100 ohm resistor with 10% tolerance will have a range between 90 and 110 ohms. A 120 ohm resistor has a range between 110 and 130 ohms. By this logic, it is preferable to produce resistors with a 10% tolerance of 100, 120, 150, 180, 220, 270, 330 and so on (rounded accordingly). This is the E12 series shown below.

Tolerance 20% E6,

Tolerance 10% E12,

Tolerance 5% E24 (and usually 2% tolerance)

Tolerance 2% E48,

E96 1% tolerance,

E192 0.5, 0.25, 0.1% and higher tolerances.

Standard resistor values:

E6 series: (20% tolerance) 10, 15, 22, 33, 47, 68

E12 series: (10% tolerance) 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82

E24 series: (5% tolerance) 10, 11, 12, 13, 15, 16, 18, 20, 22, 24, 27, 30, 33, 36, 39, 43, 47, 51, 56, 62, 68, 75, 82, 91

E48 series: (2% tolerance) 100, 105, 110, 115, 121, 127, 133, 140, 147, 154, 162, 169, 178, 187, 196, 205, 215, 226, 237, 249, 261, 274, 287, 301, 316, 332, 348, 365, 383, 402, 422, 442, 464, 487, 511, 536, 562, 590, 619, 649, 681, 715, 750, 787, 825, 6, 909, 953

E96 series: (1% tolerance) 100, 102, 105, 107, 110, 113, 115, 118, 121, 124, 127, 130, 133, 137, 140, 143, 147, 150, 154, 158, 162, 165, 169, 174, 178, 182, 187, 191, 196, 200, 205, 210, 215, 221, 226, 232, 237, 243, 249, 255, 261, 267, 274, 280, 287, 4, 301, 309, 316, 324, 332, 340, 348, 357, 365, 374, 383, 392, 402, 412, 422, 432, 442, 453, 464, 475, 487, 491, 511, 523, 6, 549, 562, 576, 590, 604, 619, 634, 649, 665, 681, 698, 715, 732, 750, 768, 787, 806, 825, 845, 866, 887, 909, 931, 959, 6

E192 series: (0.5, 0.25, 0.1 and 0.05% tolerance) 100, 101, 102, 104, 105, 106, 107, 109, 110, 111, 113, 114, 115, 117, 118, 120, 121, 123, 124, 126, 127, 129, 130, 132, 133, 135, 137, 138, 140, 142, 143, 145, 147, 149, 150, 152, 154, 156, 8, 160, 162, 164, 165, 167, 169, 172, 174, 176, 178, 180, 182, 184, 187, 189, 191, 193, 196, 198, 200, 203, 205, 208, 210, 3, 215, 218, 221, 223, 226, 229, 232, 234, 237, 240, 243, 246, 249, 252, 255, 258, 261, 264, 267, 271, 274, 277, 280, 284, 7, 291, 294, 298, 301, 305, 309, 312, 316, 320, 324, 328, 332, 336, 340, 344, 348, 352, 357, 361, 365, 370, 374, 379, 383, 8, 392, 397, 402, 407, 412, 417, 422, 427, 432, 437, 442, 448, 453, 459, 464, 470, 475, 481, 487, 493, 499, 505, 511, 517, 3, 530, 536, 542, 549, 556, 562, 569, 576, 583, 590, 597, 604, 612, 619, 626, 634, 642, 649, 657, 665, 673, 681, 690, 698, 6, 715, 723, 732, 741, 750, 759, 768, 777, 787, 796, 806, 816, 825, 835, 845, 856, 866, 876, 887, 898, 909, 920, 931, 942, 3, 965, 976, 988

When designing hardware, it is best to stick to the lowest section, i.e. It's better to use E6 rather than E12. In such a way that the number of different groups in any equipment is minimized.

To be continued

Andrey Golubev, the author of video tutorials on repairing household electronics, microwave ovens, televisions and audio equipment, dedicates his video tutorials to those who do not want to be a slave to service departments and spend many times more money on household appliances when they break down than when buying them.

Have you ever observed how experienced technicians easily find faults and masterfully handle tools and measuring instruments? Many people are ready to constantly admire someone's work, without even thinking that they can learn all this themselves! Video lessons are a fun way to learn. They are presented in accessible, simple language with good explanations.

The first video records the process of repairing an LG home theater:

Receiver repair. When starting repairs on the receiver, it is first necessary to conduct a visual inspection of the installation. Sometimes the problem is a simple failure. This rule applies not only to the repair of receivers, but to all household appliances.

Philips DVD repair:

Restoring the DVD player head cable:

Repair of microwave oven LG MS-1744:

LG microwave repair. It all started with a banal replacement of the mica gasket, and ended with the replacement of the transformer:

What to do if the microwave sparks? The mica gasket needs to be replaced. Replacing mica is not such a difficult task when repairing microwave ovens, and any housewife can do it.

We repair domestically produced Samsung PDP TV. The cause of the malfunction is a manufacturing defect.

Xoro LCD TV repair. This video shows how ridiculous malfunctions of modern television and radio equipment can be.

LG DVD repair. This video discusses replacing the optical converter on an LG DVD karaoke center.

The LCD TV does not respond to the remote control. The remote control itself is not always to blame for the lack of response to the remote control...

Samsung DVD repair. Some problems sometimes seem to be completely unrelated. So it is in this Samsung DVD repair - the failure of an element of one unit affects the operation of another.

Sven subwoofer repair. The Sven subwoofer was not repaired - the UTC2030 (TDA2030) amplifier chip had failed. Moreover, the microcircuit was torn into pieces. In addition, the path burned out.

Repairing a DVD, specifically a switching power supply for a DVD player, is not much different from repairing other switching power supplies. However, each technique has its own nuances.

Microlab amplifier repair. The cause of the malfunction was the failure of tda 2030 microcircuits

The microwave does not heat:

This video discusses a couple of cases of DVD repair when the video freezes. In the first case, all suspicions point to the head. Especially heads of this type often begin to hang as they “warm up” after 10-20 minutes of reading.

Repair of ADSL modem Intercross 5633:

Beginning radio amateur: school for beginner radio amateur, diagrams and designs for beginners, literature, amateur radio programs

Good afternoon, dear radio amateurs!
Welcome to the website ““

The site works “ Beginner radio amateur school“. The full course of study includes classes ranging from the basics of radio electronics to the practical design of amateur radio devices of average complexity. Each lesson is based on providing students with the necessary theoretical information and practical video materials, as well as homework. During the course of study, each student will receive the necessary knowledge and skills in the full cycle of designing radio-electronic devices at home.

In order to become a student of the school, you need a desire and subscription to the site's news either through FeedBurner, or through a standard subscription window. Subscription is required to receive new lessons, lesson videos and homework in a timely manner.

Only those who have subscribed to the training course at the “Beginner Radio Amateur School” will have access to video materials and homework assignments for the classes.

For those who decide to study amateur radio with us, in addition to subscribing, it is necessary to carefully study the preparatory articles:
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You can leave all questions, suggestions and comments in the comments in the “Beginners” section.

First lesson.

Second lesson.
Radio amateur laboratory. We assemble the power supply.

We decide on the scheme. How to check radio elements.

Preparing parts.
Location of parts on the board.
Making a board in the easiest way.

Soldering the circuit.
Functionality check.
Making a housing for the power supply.
Making a front panel using the “Front Designer” program.

Third lesson.
Radio amateur laboratory. We assemble a functional generator.



Designing a printed circuit board using the “Sprint Layout” program.
Use of LUT (laser ironing technology) to transfer toner to the board.

The final version of the board.
Silk-screen printing.
Checking the functionality of the generator.
Setting up the generator using the special program “Virtins Multi-Instrument”

Fourth lesson.
Assembling a light and sound device using LEDs

Preface.
We decide on a diagram and study the characteristics of the main parts.

Photoresists and their applications.
A little about the “Cadsoft Eagle” program. Installation and Russification of the official version.

We study the Cadsoft Eagle program:
– initial program settings;
– creating a new project, a new library and a new element;
– creation of a schematic diagram of the device and printed circuit board.

We clarify the scheme;
We make a printed circuit board in the Cadsoft Eagle program;
We service the board tracks with the “Rose” alloy;
We assemble the device and check its performance with a specialized program and generator;
Well, in the end, we are happy with the results.

Let us summarize some of the results of the work of the “School”:

If you went through all the steps sequentially, then your result should be as follows:

1. We learned:
- what is Ohm’s law and studied 10 basic formulas;
– what is a capacitor, resistor, diode and transistor.
2. We learned:
♦ produce housings for devices in a simple way;
♦ tinning printed conductors in a simple way;
♦ apply “silk-screen printing”;
♦ produce printed circuit boards:
– using a syringe and varnish;
– using LUT (laser ironing technology);
– using PCB with applied film photoresist.
3. We studied:
- program for creating front panels “Front Designer”;
– an amateur program for setting up various devices “Virtins Multi-Instrument”;
– program for manual design of printed circuit boards “Sprint Layout”;
– program for automatic design of printed circuit boards “Cadsoft Eagle”.
4. We have produced:
- bipolar laboratory power supply;
– function generator;
– color music using LEDs.
In addition, from the “Practicum” section we learned:
- assemble simple devices from scrap materials;
– calculate current-limiting resistors;
– calculate oscillatory circuits for radio devices;
– calculate the voltage divider;
– calculate low and high pass filters.

In the future, the “School” plans to produce a simple VHF radio receiver and a radio observer receiver. This will most likely be the end of the “School’s” work. In the future, the main articles for beginners will be published in the “Workshop” section.

In addition, a new section on studying and programming AVR microcontrollers has been started.

Works of beginner radio amateurs:

Intigrinov Alexander Vladimirovich:

Grigoriev Ilya Sergeevich:

Ruslan Volkov:

Petrov Nikit Andreevich:

Morozas Igor Anatolievich:

In everyone’s life, situations arise when it is necessary to repair some radio-electronic device, from Christmas tree garland to complex household appliances. With minimal skills in working with tools, many types of work can be done independently. This is usually limited to soldering a broken wire or searching for a burnt-out lamp. More serious types of work require knowledge in the field of electronics, experience, and the availability of instruments and tools.

Knowledge will not be superfluous at all, but you should not immediately try to comprehend the structure and repair, in particular, of a TV. Most likely, nothing will come of this. At best, the repair will fail, and at worst, new problems will be added. It is better to start studying radio and electrical engineering from the very basics and consolidate them with practical work. To do this, you first need a very small fleet of tools and devices, which can then be replenished as the need arises.

What you need to know

It is best to take radio electronics lessons from more experienced people, but in the era of the widespread development of the Internet, it is quite possible to master knowledge on your own. There is a sufficient number of training videos and accessible literature on the Internet for free reference. If you wish, you can even subscribe to training courses and lessons.

What a novice radio amateur should know, and what must be present in the training course:

  • Basics of Electronics. These are, first of all, Ohm's laws, Kirchhoff's laws, and power calculations. It is necessary to know the calculation of series and parallel connections of resistors and capacitors. Without this knowledge, further steps are simply meaningless;
  • Know how to use measuring instruments. For all measuring instruments, it is important to be able to correctly select the measurement limit, and for pointer instruments, it is additionally to be able to determine the value of the measurement scale division and take readings;

  • Know the operating principle and structure of the simplest radioelements: resistors, capacitors, inductors, transformers, diodes and transistors. It is necessary to navigate the parameters of the elements and, based on the operation of the circuit, determine which of them are the most important and critical in a given section of the circuit. At first, there is no need to thoroughly know how the p-n junction of a diode and transistor works, but the operating features that characterize the most important parameters must be remembered;
  • Be able to read radios and electrical diagrams. To do this, you need to remember the designations of the elements on the circuit diagrams;
  • Know the principles of labeling radioelements, be able to decipher abbreviated and coded designations and be able to convert multiple measurement values ​​(megaohms into kiloohms, microfarads into picofarads, and so on);

  • Know how to use a soldering iron, choose the right solder and flux for soldering.

Important! Most radio circuits, although they require low-voltage power supply, use for these purposes a conversion of the mains voltage, which is life-threatening. Basic safety precautions are important for maintaining health and life.

What tools and equipment are needed

A radio amateur workshop must have several mandatory items. Over time, with the acquisition of skills and knowledge, the range can be expanded, but at first only a few varieties are needed.

The most important tool for a radio amateur is a soldering iron. To ensure safety and prevent electric shock or damage to circuit elements, the soldering iron must be low-voltage - with a supply voltage of no more than 42V. If we talk about power, then a 25-watt soldering iron is enough for soldering most circuit elements. It is, of course, not very suitable for soldering leads of powerful radio components, and if in doubt, you can take a tool with a power of 40W. No longer necessary, since even in skillful hands, using such a soldering iron can lead to overheating and failure of radio elements, and peeling of printed conductors on boards.

It makes no sense for a novice radio amateur to purchase a complex and expensive soldering station. Having learned how to use a regular soldering iron correctly, you can think about purchasing a more complex tool, but having learned to work with a soldering station, it will be quite difficult to handle a regular soldering iron.

Measuring device

Currently on sale you can find a wide variety of all kinds of measuring instruments, varying degrees of complexity, accuracy and price range.

When working with electrical circuits, it is most important to measure the following parameters:

  • Resistance;
  • AC and DC voltage;
  • Alternating and direct current;
  • More complex work will require measuring the frequency and shape of signals, transistor parameters, and inductance values.

The most common combination instruments measure voltage, current and resistance. Previously, they were called avometers (ampere-volt-ohmmeter), but now, mainly, testers or multimeters, since they are capable of measuring several more parameters.

Most devices are based on digital signal processing and have a symbolic display. Like most digital devices, they have many positive qualities:

  • High measurement accuracy;
  • Possibility of automatic determination of the measurement limit and signal polarity;
  • Remembering the result.

At the same time, analog instruments, having less accuracy, allow you to see a clear change in the measured value according to the position of the arrow. It is possible to observe and measure rapidly changing parameters.

Digital devices require some time to set the readings. The main disadvantage is the requirement to initially know the correct polarity of the signal source and its possible value in order to select the measurement limit. This is also the reason for the difficulty that beginner radio amateurs have - correctly reading the readings of the pointer instrument.

With an analog device, if you have some skill, you can monitor the condition and serviceability of electrolytic capacitors, which is very difficult to do with a digital multimeter.

It is better for a beginner to use a pointer instrument in his work, since during the learning process he acquires useful skills in working with measuring equipment, and the accuracy of measurements is not fundamental. In addition, such a device does not require a built-in power supply to measure current and voltage.

For a novice radio amateur, even a tester released in the middle of the last century is quite suitable, since the measurement principle, rules of use and characteristics of avometers have practically not changed since that time, and the accuracy and reliability of even the oldest devices is sometimes much higher than that of modern cheap Chinese avometers. The amateur radio hobby of most modern electronics engineers began with the most common domestically produced tester, the Ts20.

Tools and materials

A radio amateur laboratory is impossible without a minimum of tools:

  • Nippers (side cutters);
  • Tweezers;
  • A set of screwdrivers with various blade shapes;
  • A set of various fasteners (bolts, nuts, washers);
  • Insulated flexible and single-core wires.

Solder and flux are required. The most trusted type of solder is POS60, which has a low melting point. Both before and now it is the main solder for soldering radioelements in the post-Soviet space.

Rosin or its solution in ethyl alcohol is mainly used as a flux. You can use other compositions, for example, LTI120, but rosin is more versatile and has a minimal cost.

Important! When soldering radioelements and wires, do not use acidic or active fluxes. Quickly and efficiently performed soldering will be hopelessly damaged by corrosion after a short time.

Safety precautions

Radio technology for beginners should provide the highest level of safety. It has already been noted about low-voltage soldering irons, but it should be noted that most hobbyists immediately use mains power supplies when constructing and repairing devices. It will be much safer to purchase or ask to make a powerful isolation transformer with a unity transformation ratio for your home laboratory. Providing the same 220V AC voltage at the output, it will provide reliable galvanic isolation from the supply network.

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