Interesting radio circuits for radio amateurs. Electronic homemade products for radio amateurs and novice electricians. Fluorescent lamp power supply circuit

Beginner radio amateurs who are interested in self-assembly circuits and repair of various electronic devices, get lost in a sea of numerous terms and details. Meanwhile, you can give a number of tips on what knowledge is needed first of all, what instruments to use, how to navigate when choosing circuit elements.

Required knowledge

It is very important for radio amateurs:

know and understand the basic laws of electrical engineering;
be able to navigate using diagrams;
clearly define the role of each element in the diagram and visually represent what it looks like.

Important! Theoretical knowledge must be constantly supported by practice.

Tools and devices

For assembling amateur radio circuits and homemade designs You must have the following tools:

A soldering iron, the power of which must be chosen average - no more than 40 W. More advanced craftsmen are thinking about purchasing a soldering station;
Side cutters. Not too massive a tool for working with radio devices;

Tin-lead solder exists in the form of wire.

Important! Among all the devices, the main, and often the only, is a digital multimeter or analog tester, with which you can measure all the main parameters of the circuit.

Before you begin assembling simple and interesting radio circuits made with your own hands, you can practice dismantling old radio equipment. At the same time, practical skills in soldering work are formed.

In ancient TVs with lamps, a completely suitable thing is a supply transformer. It can be used in many homemade radios. For example, assemble a charger for car battery or power supply for a sound amplifier. The main thing is to know its technical data;
IN outdated devices radio electronics: television equipment, video recorders, ordinary tape recorders, there are entire microcircuits ready for use. For example, we can name an audio amplifier, the circuit of which is constructed by simply assembling components, without etching on printed circuit boards, etc.;
The tone control is also used in finished form. At the same time, the assembled audio amplifier will receive new options: the ability to control the low-frequency and high-frequency ranges, change the balance in stereo speakers;
Basically, all devices manufactured by radio amateurs operate on five-, nine- and twelve-volt power supplies. Such power supplies from old equipment will be the most useful.

As housings for circuits, you can use any available designs or buy ready-made ones, different sizes and forms. Housings from non-working devices are often used for new homemade radios.

A non-working power supply from a computer is very valuable, where does it come from:

a lot of radio components: transistors, capacitors, diodes, resistances, which are useful for assembled devices;
cooling radiators are an important accompanying element for high-power transistors;
good wires;
the body itself - perfect place to accommodate new structures.

Circuit assembly methods

Wall-mounted installation. Simple soldering of components in accordance with the developed circuit. Soldered assemblies can be installed on supporting platforms. The method is suitable for constructing radio circuits from a small number of parts;
Installation on a printed circuit board - a textolite platform on which foil tracks are made as connecting conductors.

The second method is divided into several options:

Mechanical. Cutting paths with a sharp object to eliminate contact connections in unnecessary places;
Chemical. Using varnish or paint, you need to draw the required diagram on the foil. Then immerse in a special composition - a solution of ferric chloride. After processing, a pattern corresponding to the design will be obtained, and all areas without varnish will be removed by dissolution;
Laser ironing.

What schemes should I start with?

The classic start for radio amateurs is to make a simple detector receiver. The circuit contains a small number of components and can be assembled by anyone. Then you can supplement the device with an audio amplifier using transistors. With the arrival of experience and understanding, work with microcircuits begins.

A large number of interesting and very simple options homemade radios with descriptions of parts and diagrams are available on the RadioKot website. You can, for example, assemble color music, pulsed clock illumination, a stereo transmitter and much more. There are also useful forums where you can clarify complex issues and communicate with experienced professionals.

As you gain skills, your interest in assembling complex devices will increase. Radio-electronic homemade products are one of the the most exciting activities for people of all ages.

Video

You can make simple electronic circuits for home use with your own hands, even without deep knowledge of electronics. In fact, at the everyday level, radio is very simple. Knowledge of the elementary laws of electrical engineering (Ohm, Kirchhoff), general principles operation of semiconductor devices, schematic reading skills, ability to work with electric soldering iron quite enough to assemble a simple circuit.

Radio amateur workshop

No matter how complex the scheme may have to be implemented, it is necessary to have minimum set materials and tools in your home workshop:

Side cutters;
Tweezers;
Solder;
Flux;
Circuit boards;
Tester or multimeter;
Materials and tools for making the device body.

You shouldn't buy expensive ones to begin with. professional tools and devices. Expensive Soldering Station or a digital oscilloscope will be of little help to a novice radio amateur. At first creative path The simplest instruments are quite enough, on which you need to hone your experience and skills.

Where to start

Do-it-yourself radio circuits for the home should not exceed the level of complexity that you have, otherwise it will only mean wasted time and materials. If you lack experience, it is better to limit yourself to the simplest schemes, and as you gain skills, improve them, replacing them with more complex ones.

Typically, most literature in the field of electronics for beginner radio amateurs leads classic example manufacturing of simple receivers. This especially applies to classical old literature, which does not contain so many fundamental errors compared to modern literature.

Note! These schemes were designed for the enormous power of transmitting radio stations in the past. Today, transmitting centers use less power to transmit and try to move to shorter wavelengths. Don't waste time trying to make a working radio using a simple circuit.

Radio circuits for beginners should contain a maximum of two or three active elements - transistors. This will make it easier to understand the operation of the circuit and increase the level of knowledge.

What can be done

What can be done so that it is not difficult and can be used in practice at home? There can be many options:

Apartment call;
Christmas tree garland switch;
Backlight for modding the computer system unit.

Important! Devices should not be designed to operate on household network alternating current, there is not enough experience yet. This is dangerous both for life and for others.

Quite simple circuits have amplifiers for computer speakers, made on specialized integrated circuits. Devices assembled on their basis contain a minimum number of elements and require virtually no adjustment.

You can often find circuits that need basic modifications and improvements that simplify manufacturing and configuration. But this should be done by an experienced master so that the final version is more accessible to a beginner.

What to use for the design

Most literature recommends constructing simple circuits on circuit boards. Nowadays this is quite simple. There is a wide variety of circuit boards with various configurations mounting holes and printed tracks.

The installation principle is that the parts are installed on the board in free spaces, and then the necessary pins are connected to each other by jumpers, as indicated on the circuit diagram.

With due care, such a board can serve as the basis for many circuits. The power of the soldering iron for soldering should not exceed 25 W, then the risk of overheating radio elements and printed conductors will be minimized.

The solder should be low-melting, like POS-60, and as a flux it is best to use pure pine rosin or its solution in ethyl alcohol.

Highly qualified radio amateurs can develop a drawing themselves printed circuit board and perform it on foil material, on which radioelements are then soldered. The design developed in this way will have optimal dimensions.

Design of the finished structure

Looking at the creations of beginners and experienced craftsmen, one can come to the conclusion that assembling and adjusting the device is not always the most difficult part of the design process. Sometimes a properly functioning device remains a set of parts with soldered wires, not covered by any housing. Nowadays, you no longer have to worry about making a case, because on sale you can find all kinds of sets of cases of any configuration and size.

Before you start manufacturing the design you like, you should fully think through all the stages of the work: from the availability of tools and all radio elements to the design of the housing. It will be completely uninteresting if during the work it turns out that one of the resistors is missing, and there are no replacement options. It is better to carry out the work under the guidance of an experienced radio amateur, and, in as a last resort, periodically monitor the manufacturing process at each stage.

Video

DIY motion sensor connection diagram

It happens that you need to install lighting in your dacha or in your home. will be triggered by movement or a person or someone else.

A motion sensor, which I ordered from Aliexpress, works well with this function. The link to which will be below. By connecting light through a motion sensor, when a person passes through his field of vision, the light turns on and stays on for 1 minute. and turns off again.

In this article I’ll tell you how to connect such a sensor if it doesn’t have 3 contacts, but 4 like this one.

DIY power supply from an energy-saving light bulb

When to get 12 Volt for LED strip , or for some other purpose, there is an option to make such a power supply with your own hands.

DIY fan speed controller

This regulator allows for smooth adjustment variable resistor fan speed.

The circuit of the floor fan speed controller turned out to be the simplest. To fit into the case from an old Nokia phone charger. The terminals from a regular electrical outlet also fit in there.

The installation is quite tight, but this was due to the size of the case..

DIY plant lighting

There may be a problem with lack of lighting plants, flowers or seedlings, and there is a need for artificial light for them, and this is the kind of light we can provide on LEDs with your own hands.

DIY brightness control

It all started after I installed halogen lamps for lighting at home. When turned on, they often burned out. Sometimes even 1 light bulb a day. Therefore, I decided to make a smooth switching on of the lighting based on a brightness control with my own hands, and I am attaching a diagram of the brightness control.

DIY refrigerator thermostat

It all started when I returned from work and opened the refrigerator to find it warm. Turning the thermostat control did not help - the cold did not appear. Therefore, I decided not to buy a new block, which is also rare, but to make it myself electronic thermostat on ATtiny85. The difference with the original thermostat is that the temperature sensor is on the shelf and not hidden in the wall. In addition, 2 LEDs appeared - they signal that the unit is turned on or the temperature is above the upper threshold.

DIY soil moisture sensor

This device can be used for automatic watering in greenhouses, flower greenhouses, flower beds and indoor plants. Below is a diagram that can be used to make the simplest sensor(detector) of soil moisture (or dryness) with your own hands. When the soil dries out, voltage is applied with a current of up to 90 mA, which is quite enough, turn on the relay.

It is also suitable for automatically turning on drip irrigation to avoid excess moisture.

Fluorescent lamp power supply circuit

Power scheme fluorescent lamp.

Often when it fails energy saving lamps, in it burns power supply circuit, and not the lamp itself. As is known, LDS with burnt filaments, it is necessary to supply the network with rectified current using a starterless starting device. In this case, the filaments of the lamp are shunted with a jumper and to which the high voltage to turn on the lamp. There is an instantaneous cold ignition of the lamp, with a sharp increase in voltage across it, upon start-up without preheating the electrodes. In this article we will look at starting an LDS lamp with your own hands.

USB keyboard for tablet

Somehow, suddenly, I took something and decided to buy a new keyboard for my PC. The desire for novelty is irresistible. Changed the background color from white to black, and the letter color from red-black to white. A week later, the desire for novelty naturally disappeared like water into sand (an old friend is better than two new ones) and the new thing was sent to the closet for storage - until better times. And now they came for her, she didn’t even imagine that it would happen so quickly. And therefore the name would be even better suited not which is, but how to connect a usb keyboard to a tablet.

DIY clock with IN-14 lamps

I have long wanted to post an article on making DIY watches with IN-14 lamps, or as they say, a watch in the steam punk style.

I will try step by step and stopping at key points state only the most important things. The clock indication is clearly visible both day and night, and they themselves look very nice, especially in a good wooden case. Anyway, let's get started.

Those who do radio electronics at home are usually very inquisitive. Amateur radio circuits and homemade products will help you find a new direction in your creativity. Perhaps someone will find it for themselves original solution one problem or another. Some homemade products use ready-made devices, connecting them in various ways. For others, you need to completely create the circuit yourself and make the necessary adjustments.

One of the most simple homemade products. More suitable for those who are just starting to craft. If you have an old but working cell phone with a button to turn on the player, you can use it, for example, to make a doorbell for your room. The advantages of such a call:

First you need to make sure that the selected phone is capable of producing a sufficiently loud melody, after which it must be completely disassembled. Basically, the parts are secured with screws or staples, which are carefully folded back. When disassembling, you will need to remember what goes with what, so that later you can put everything back together.

The player's power button is unsoldered on the board, and two short wires are soldered in its place. These wires are then glued to the board so the solder doesn't come off. The phone is going. All that remains is to connect the phone to the call button via a two-wire wire.

Homemade products for cars

Modern cars are equipped with everything you need. However, there are times when it is simply necessary homemade devices. For example, something broke, they gave it to a friend, and the like. That’s when the ability to create electronics with your own hands at home will be very useful.

The first thing you can tamper with without fear of damaging your car is the battery. If you don’t have a battery charger at hand at the right time, you can quickly assemble it yourself. To do this you will need:

A transformer from a tube TV is ideal. Therefore, those who are interested in homemade electronics never throw away electrical appliances in the hope that they will be needed someday. Unfortunately, two types of transformers were used: with one and with two coils. To charge a battery at 6 volts, any will do, but for 12 volts only two.

On wrapping paper such a transformer shows the terminals of the windings, the voltage for each winding and the operating current. To power the filaments of electronic lamps, a voltage of 6.3 V is used. high current. The transformer can be remade by removing unnecessary secondary windings, or leave everything as is. In this case, the primary and secondary windings are connected in series. Each primary is rated at 127 V, so combining them produces 220 V. The secondary are connected in series to produce an output of 12.6 V.

Diodes must withstand a current of at least 10 A. Each diode requires a radiator with an area of at least 25 square centimeters. They are connected into a diode bridge. Any electrical insulating plate is suitable for fastening. A 0.5 A fuse is included in the primary circuit, and a 10 A fuse in the secondary circuit. The device does not tolerate short circuit, so when connecting the battery, do not confuse the polarity.

Simple heaters

During the cold season, it may be necessary to warm up the engine. If the car is parked where it is electricity, this problem can be solved using a heat gun. To make it you will need:

asbestos pipe;
nichrome wire;
fan;
switch.

Diameter asbestos pipe selected according to the size of the fan that will be used. The performance of the heater will depend on its power. The length of the pipe is everyone's preference. You can collect it a heating element and a fan, only a heater is possible. When choosing last option we'll have to figure out how to let it in air flow on heating element. This can be done, for example, by placing all components in a sealed housing.

Nichrome wire is also selected according to the fan. The more powerful the latter, the larger diameter nichrome can be used. The wire is twisted into a spiral and placed inside the pipe. For fastening, bolts are used that are inserted into the drilled holes in the pipe. The length of the spiral and their number are selected empirically. It is advisable that the coil does not become red hot when the fan is running.

The choice of fan will determine what voltage needs to be supplied to the heater. When using a 220 V electric fan, you will not need to use an additional power source.

The entire heater is connected to the network via a cord with a plug, but it itself must have its own switch. It can be either just a toggle switch or an automatic machine. The second option is more preferable, it allows you to protect shared network. To do this, the operation current of the machine must be less than the operation current of the room machine. A switch is also needed to quickly turn off the heater in case of problems, for example, if the fan does not work. This heater has its disadvantages:

harmful to the body from asbestos pipes;
noise from a running fan;
smell from dust falling on the heated coil;
fire hazard.

Some problems can be solved by using another homemade product. Instead of an asbestos pipe, you can use a coffee can. To prevent the spiral from closing on the jar, it is attached to a textolite frame, which is fixed with glue. A cooler is used as a fan. To power it, you will need to collect another electronic device- a small rectifier.

Homemade products bring those who do them not only satisfaction, but also benefits. With their help, you can save energy, for example, by turning off electrical appliances that you forgot to turn off. A time relay can be used for this purpose.

The simplest way to create a time-setting element is to use the charging or discharging time of a capacitor through a resistor. Such a chain is included in the base of the transistor. The circuit will require the following parts:

high-capacity electrolytic capacitor;
transistor p-n-p type;
electromagnetic relay;
diode;
variable resistor;
fixed resistors;
DC source.

First you need to determine what current will be switched through the relay. If the load is very powerful, you will need to connect it. magnetic switch. The starter coil can be connected via a relay. It is important that the relay contacts can operate freely without sticking. Based on the selected relay, a transistor is selected and it is determined what current and voltage it can operate with. You can focus on KT973A.

The base of the transistor is connected through a limiting resistor to a capacitor, which, in turn, is connected through a bipolar switch. The free contact of the switch is connected through a resistor to the power supply negative. This is necessary to discharge the capacitor. The resistor acts as a current limiter.

The capacitor itself is connected to the positive bus of the power source through a variable resistor with high resistance. By selecting the capacitance of the capacitor and the resistance of the resistor, you can change the delay time interval. The relay coil is shunted by a diode, which turns on in the opposite direction. This circuit uses KD 105 B. It closes the circuit when the relay is de-energized, protecting the transistor from breakdown.

The scheme works as follows. In the initial state, the base of the transistor is disconnected from the capacitor, and the transistor is closed. When the switch is turned on, the base is connected to the discharged capacitor, the transistor opens and supplies voltage to the relay. The relay operates, closes its contacts and supplies voltage to the load.

The capacitor begins to charge through a resistor connected to the positive terminal of the power source. As the capacitor charges, the base voltage begins to rise. At a certain voltage value, the transistor closes, de-energizing the relay. The relay switches off the load. In order for the circuit to work again, you need to discharge the capacitor; to do this, switch the switch.

Schemes of homemade measuring instruments

A device circuit developed on the basis of a classic multivibrator, but instead of load resistors, transistors with opposite main conductivity are included in the collector circuits of the multivibrator.

It's good if you have an oscilloscope in your laboratory. Well, if it is not there and it is not possible to buy it for one reason or another, do not be upset. In most cases, it can be successfully replaced by a logic probe, which allows you to monitor the logical levels of signals at the inputs and outputs of digital integrated circuits, determine the presence of pulses in the controlled circuit and reflect the received information visually (light-color or digital) or audio (tone signals of various frequencies ) forms. When setting up and repairing structures based on digital integrated circuits, it is not always so necessary to know the characteristics of pulses or exact values voltage levels. Therefore, logic probes make the setup process easier, even if you have an oscilloscope.

A huge selection of different pulse generator circuits is presented. Some of them generate a single pulse at the output, the duration of which does not depend on the duration of the triggering (input) pulse. Such generators are used for a wide variety of purposes: simulating input signals of digital devices, when testing the functionality of digital integrated circuits, the need to feed to some device a certain number pulses with visual control of processes, etc. Others generate sawtooth and rectangular pulses of various frequencies, duty cycle and amplitude

Repair of various components and devices of low-frequency electronic equipment and technology can be greatly simplified if you use a function generator as an assistant, which makes it possible to study the amplitude-frequency characteristics of any low-frequency device, transient processes and nonlinear characteristics of any analog devices, and also has the ability to generate pulses rectangular shape and simplifying the process of setting up digital circuits.

When setting up digital devices, you definitely need one more device - a pulse generator. An industrial generator is a rather expensive device and is rarely on sale, but its analogue, although not as accurate and stable, can be assembled from available radio elements at home

However, creating a sound generator that produces a sinusoidal signal is not easy and quite painstaking, especially in terms of setup. The fact is that any generator contains at least two elements: an amplifier and a frequency-dependent circuit that determines the oscillation frequency. It is usually connected between the output and input of the amplifier, creating a positive feedback(POS). In the case of an RF generator, everything is simple - just an amplifier with one transistor and an oscillating circuit that determines the frequency. For the audio frequency range, it is difficult to wind a coil, and its quality factor is low. Therefore, in the audio frequency range, RC elements are used - resistors and capacitors. They filter the fundamental harmonics quite poorly, and therefore the sine wave signal turns out to be distorted, for example, limited by peaks. To eliminate distortion, amplitude stabilization circuits are used to maintain a low level of the generated signal when the distortion is not yet noticeable. It is the creation of a good stabilizing circuit that does not distort the sinusoidal signal that causes the main difficulties.

Often, after assembling the structure, the radio amateur sees that the device does not work. After all, a person does not have sense organs that allow him to see electric current, electromagnetic field or processes occurring in electronic circuits. Radio measuring instruments - the eyes and ears of a radio amateur - help to do this.

Therefore, we need some means of testing and checking telephones and loudspeakers, audio amplifiers, and various sound recording and sound reproducing devices. Such a remedy is amateur radio circuits audio frequency signal generators, or, more simply, a sound generator. Traditionally, it produces a continuous sine wave whose frequency and amplitude can be varied. This allows you to check all ULF stages, find faults, determine the gain, take amplitude-frequency characteristics (AFC) and much more.

We consider a simple homemade amateur radio attachment that turns your multimeter into a universal device for testing zener diodes and dinistors. PCB drawings available