Electrical circuits and electronics

In the last article of my blog, I talked about the qristal oscillator, today I will show and tell you how it can be used as a pulse generator.

Crystal oscillator circuits are generally constructed using bipolar transistors or FETs. This is because although operational amplifiers can be used in many different low frequency (≤100kHz) oscillator circuits, operational amplifiers just do not have the bandwidth to operate successfully at the higher frequencies suited to crystals above 1MHz.

This pulse generator can be used in various electrical circuits where a constant pulse frequency and small size of the structure of your device are required.

Sources:
https://www.elprocus.com/crystal-oscillator-circuit-and-working/
https://www.ruselectronic.com/kvartsevyj-generator/

Hello my favorite readers. Today I will tell you about the сrystal oscillator.

One of the most important features of any oscillator is its frequency stability, or in other words its ability to provide a constant frequency output under varying load conditions.
Crystal oscillator. At different frequencies are needed as reliable and stable sources of harmonic oscillations, so that the digital microcontroller can rely on the reference frequency, and operate with it in the future, during the operation of the digital device.Thus, a сrystal oscillator.Is a reliable replacement for an oscillating LC circuit.

The quartz crystal used in a quartz Crystal Oscillator is a very small, thin piece or wafer of cut quartz with the two parallel surfaces metallised to make the required electrical connections. The physical size and thickness of a piece of quartz crystal is tightly controlled since it affects the final or fundamental frequency of oscillations. The fundamental frequency is generally called the crystals “characteristic frequency”.

The equivalent electrical circuit for the quartz crystal shows a series RLC circuit, which represents the mechanical vibrations of the crystal, in parallel with a capacitance, Cpwhich represents the electrical connections to the crystal. Quartz crystal oscillators tend to operate towards their “series resonance”.

Source:
http://electrik.info/main/praktika/1222-kvarcevyy-rezonator-struktura-princip-raboty-kak-proverit.html

https://www.ruselectronic.com/kvartsevyj-rezonator/

Hi my comrades, this time I will tell you about darlington transistors. The Darlington transistor is a very interesting schematic solution. Thanks to these transistors, you can build sensitive or energy-consuming devices.

The Darlington Transistor named after its inventor, Sidney Darlington is a special arrangement of two standard NPN or PNP bipolar junction transistors (BJT) connected together. The Emitter of one transistor is connected to the Base of the other to produce a more sensitive transistor with a much larger current gain being useful in applications where current amplification or switching is required. The darlington transistor is a compound structure of a particular design made by two bipolar transistors connected in such a way that the current amplified by the first transistor is amplified further by the second one, This configuration gives a much higher current gain than each transistor taken separately.

The advantages of darlington transistors from simple bipolar transistors:

1)Large current gain;

2)High sensitivity;

3)Low voltage unlocking transistor (0.2V … 0.4 V);

4)High current transmit power.

In this video you can learn more about the principle of the darlington transistor

Source: go-radio.ru/coctavnoy-transistor.html
http://www.skilldiagram.com/gl2-16.html
http://digteh.ru/Sxemoteh/ShVklTrz/Darlington/
https://www.youtube.com/watch?v=m9HPXbcc6S4

And I greet you again. Today I would like to tell you about logic chips.

The digital world of electronics is based on the laws of discrete mathematics. This means that we must move to the system of «truth» and «false» (1 or 0). All this is necessary to process an analog or digital signal into the signal we need.

Logic elements have one or more inputs and one or two (usually inverse to each other) output. The values ​​»0″ and «1» of the output signals of the logic elements are determined by the logical function that the element performs, and the values ​​of «0» and «1» of the input signals playing the role of independent variables. There are elementary logical functions from which one can compose any complex logical function.

These elements implement certain logical dependencies between input and output signals. Logical elements are usually used to build logic circuits of computers.

Source:
http://electricalschool.info/electronica/1918-logicheskie-jelementy-i-ili-ne-i-ne-ili.html https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-002-circuits-and-electronics-spring-2007/lecture-notes/

Hi my friends, to day i will tell you about opamp. Аn operational amplifier is a high gain DC amplifier that can be very large, up to millions. Often there is a gain of 200,000. Operational amplifiers are capable of amplifying AC signals, as well as DC signals, they are more often used in measuring equipment to amplify DC signals.

Operational amplifiers do not have infinite input impedances and zero output impedances. Although it is possible input impedance of several trillion Ohms, and output impedances close to zero. As a result, the output signals from such opamps can be very precisely controlled. For this reason, opamps are considered precision amplifiers.

All operational amplifiers have two inputs. Minus in the diagram means one input, plus — the other. The symbol of the operational amplifier can be found on the diagram by the plus and minus signs on the vertical side of the triangle. These are distinctive features of the op amp design.

Source:
https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-002-circuits-and-electronics-spring-2007/lecture-notes/
https://ru.wikipedia.org/wiki

Hello dear friends, today I will tell you about filters. An electrical frequency filter is required in the circuit to pass only the desired frequency range, signals in the form of current or voltage. It is a quadrupole.

Electric Filter Classification

These types of electrical filters are determined:

— High Frequency. Pass frequencies: from the cutoff frequency to infinity. The device assumes parallel connection of inductance and series arrangement of capacitance. It can also consist of a combination with a resistor

— Low frequency. Pass frequencies: from zero to the cutoff frequency. The design involves the parallel placement of the capacitance and the series arrangement of the inductance.

-Notch filters. Do not miss only certain frequencies, and the rest pass. At parallel connection of high-frequency and low-frequency filters and observance of specifications the blocking filter is formed.

— Bandpass filters. Pass only a certain range of frequencies. It can be a combination of low-frequency and high-frequency filters that are cascaded (if certain conditions are met — tuned to the necessary frequencies).

Given the scheme of links, electrical filters can be single and multilink. Performing the classification by type of elements, the devices are divided into: non-inductive (include elements C and R), reactive (include elements C and L) and others.

Features and application of filters:

-pass or not pass a certain range of frequencies;

— save the required performance at the output;

— provide high speed signal processing;

— have broad technical capabilities for use.

Source:https://ru.wikipedia.org/wiki/Фильтр_(электроника)
https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-002-circuits-and-electronics-spring-2007/lecture-notes/

Hello my friend, today we will talk about electronics in human life. Electronics is such a big part of our daily life that we hardly think about what a world would be like without electronics. Everything, from cooking to astronautics, somehow uses electronics or electronic components. Our family car has a lot of electronic components, like our stove, laptop and mobile phone with a computer.

Today, technology has reached a level where electronics produces electronics itself. We are talking about huge factories with automatic production lines, where an electric supporting crane beam and other useful devices are created. In fact, what the fantasy writers of the past dreamed of — fully automatic factories — has already become a reality today. A person at such a plant is required only as a controlling function plus some repair needs.

Source:
http://computer.damotvet.ru/other/925747.htm /
http://ant-design.ru/articles/elektronika-v-jizni-cheloveka /
http://www.media-metrix.com/rol-elektroniki-v-zhizni-cheloveka/

Hello everyone, after a long pause, I would like to tell you how to read electrical circuits. The topic is very interesting, so I advise you to grab a cup of tea or coffee with you. And we begin.Beginners, who are trying to assemble their own electronic circuits and devices, face the very first question in their new activity, how to read electrical circuits? The question is, in fact, serious, because before you assemble a scheme, it is necessary to somehow mark it on paper. Or find a ready-made version for implementation. That is, reading electrical circuits is the main task of any radio amateur or electrician. What is an electrical circuit.

In order to learn how to read electrical circuits, you need to know the conditional graphic designation of radio components — this is the most important thing you need to know!

In the modern world of radio electronics, there are more than 2 thousand symbols of radio elements. I will give some of them:

This is only a small part of what you need to know, I repeat, that in the world there are a huge variety of symbols of radio elements. To learn how to read any electrical circuit will have to learn a lot of symbols and understand what kind of detail is shown in the figure. All this can be learned in special radio engineering books.

Source:
http://madelectronics.ru/uchebnik/oboznacheniya-elektronnyh-radioelementov.htm

    Hi, today I will talk about the most «simple» about electricity. After all, electricity is the most interesting, mysterious and sometimes dangerous phenomenon.

   Modern life can not be imagined without electricity, this type of energy is used by mankind most fully. However, not all adults are able to recall the definition of electric current from a school physics course (this is a directed flow of elementary particles with a charge), very few people understand what it is.

   What is electricity?

           I’ll start with the most boring and unloved by all students — these are theories

Electricity or electric current is called a directionally moving stream of charged particles, such as electrons. Also called electricity is the energy produced by such a movement of charged particles, and the illumination that is obtained on the basis of this energy. The term «electricity» was introduced by the English scientist William Gilbert in 1600 in his essay «On a magnet, magnetic bodies and a large magnet-Earth.»

Gilbert conducted experiments with amber, which, as a result of friction on the cloth, was able to attract other light bodies, that is, it acquired a certain charge. And since amber is translated from Greek as an electron, the phenomenon observed by scientists has been called «electricity.»

Some facts about electricity:

Electricity is capable of creating an electric field around the conductors of an electric current or charged bodies. By means of an electric field, it is possible to influence other bodies having an electric charge.

Electric charges, as we all know, are divided into positive and negative. This choice is conditional, however, due to the fact that it has been made historically for a long time, it is only for this reason that a certain sign is attached to each charge.

The bodies, which are charged with the same type of mark, repel each other, and which have different charges, on the contrary, are attracted.

During the movement of charged particles, that is, the existence of electricity, in addition to the electric field there is a magnetic field. This allows you to establish a relationship between electricity and magnetism.

Interestingly, there are bodies that conduct electrical current or bodies with very high resistance .. This was discovered by the English scientist Stephen Gray in 1729.

History of the discovery of electricity:

To begin with, it must be said that there is no such scientist who can be considered the discoverer of electricity, since from ancient times to this day many scientists study its properties and learn something new about electricity.

However, the most great and powerful in terms of discoveries related to electricity, was Nikola Tesla. He himself was born in the Austrian Empire, now it is the territory of Croatia. In his baggage of inventions and scientific works: alternating current, field theory, ether, radio, resonance and much more. Some admit the possibility that the phenomenon of “Tunguska meteorite” is nothing but the work of the hands of Nikola Tesla himself, namely the explosion of enormous power in Siberia.

Electricity in nature:

    For a time it was believed that electricity does not exist in nature. However, after B. Franklin established that lightning has an electrical nature of occurrence, this view has ceased to exist.The value of electricity in nature, as in human life is quite huge. After all, lightning led to the synthesis of amino acids and, consequently, to the emergence of life on earth.Processes in the nervous system of humans and animals, for example, movement and respiration, occur due to the nerve impulse that occurs due to electricity existing in the tissues of living beings.

Some types of fish use electricity, or rather electric discharges to protect against enemies, search for food under water and its getting. These fish are: eels, lamprey, electric stingrays and even some sharks. All these fish have a special electric organ that works on the principle of a capacitor, that is, it accumulates a sufficiently large electric charge, and then discharges it on the victim who has touched such a fish. Also, such a body works with a frequency of several hundred hertz and has a voltage of several volts. The current strength of the electric organ of fish varies with age: the older the fish becomes, the greater the current strength. Also, due to the electric current, fish that live at great depth are oriented in the water. The electric field is distorted by the action of objects in the water. And these distortions and help the fish navigate.

Electricity generation:

To generate electricity, power stations were specially created. At power plants with the help of generators, electric power is generated, which is then transmitted to the point of consumption via power lines. Electric current is created by the transfer of mechanical or internal energy into electrical energy. Power plants are divided into: hydroelectric, thermal nuclear, wind, tidal, solar and other power plants.

Electricity use: