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 an original solution to this or that problem. Some homemade products use ready-made devices, connecting them in different ways. For others, you need to completely create the circuit yourself and make the necessary adjustments.

One of the simplest 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 homemade devices are simply necessary. For example, something broke, they gave it to a friend, and the like. Then 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.

The wrapping paper of such a transformer shows the winding terminals, the voltage for each winding and the operating current. To power the filaments of electronic lamps, a voltage of 6.3 V with a high current is used. The transformer can be remade by removing the extra secondary windings, or you can 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 circuits, so the polarity should not be confused when connecting the battery.

Simple heaters

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

asbestos pipe;
nichrome wire;
fan;
switch.

The diameter of the asbestos pipe is 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 assemble a heating element and a fan in it, or just a heater. When choosing the latter option, you will have to think about how to allow air flow to the 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 the 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 pre-drilled holes in the pipe. The length of the spiral and their number are selected experimentally. 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 the general 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 assemble 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;
pnp type transistor;
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 a magnetic starter to connect it. 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 a 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.

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 Volts 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 unit, which is also rare, but to make an electronic thermostat myself using the 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 on which you can make a simple 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 supply circuit for a fluorescent lamp.

Often when energy-saving lamps fail, it is the power supply circuit that burns out, 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 bridged by a jumper and a high voltage is applied to it 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 cannot be overcome. 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 to present only the most important things step by step and focusing on key points. 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.

Every day there are more and more, many new articles appear, it is quite difficult for new visitors to immediately find their bearings and review at once everything that has already been written and previously posted.

I would really like to draw the attention of all visitors to individual articles that were posted on the site earlier. In order to avoid having to search for the necessary information for a long time, I will make several “entrance pages” with links to the most interesting and useful articles on individual topics.

Let's call the first such page "Useful electronic homemade products." Here we consider simple electronic circuits that can be implemented by people of any skill level. The circuits are built using a modern electronic base.

All information in the articles is presented in a very accessible form and to the extent necessary for practical work. Naturally, to implement such schemes you need to understand at least the basics of electronics.

So, a selection of the most interesting articles on the site on the topic "Useful electronic homemade products". The author of the articles is Boris Aladyshkin.

Modern electronics components greatly simplify circuit design. Even a regular twilight switch can now be assembled from just three parts.

The article describes a simple and reliable electric pump control circuit. Despite the extreme simplicity of the circuit, the device can operate in two modes: water lifting and drainage.

The article provides several diagrams of spot welding machines.

Using the described design, you can determine whether a mechanism located in another room or building is working or not. Information about the operation is the vibration of the mechanism itself.

A story about what a safety transformer is, why it is needed and how you can make it yourself.

Description of a simple device that turns off the load if the mains voltage exceeds acceptable limits.

The article discusses the circuit of a simple thermostat using an adjustable zener diode TL431.

An article about how to make a device for smoothly switching on lamps using the KR1182PM1 microcircuit.

Sometimes, when the voltage in the network is low or when soldering massive parts, it becomes simply impossible to use a soldering iron. This is where a boost power regulator for a soldering iron can come to the rescue.

An article about how you can replace a mechanical thermostat for an oil heating radiator.

Description of a simple and reliable thermostat circuit for a heating system.

The article describes a converter circuit made on a modern element base, containing a minimum number of parts and allowing to obtain significant power in the load.

An article about various ways to connect a load to a control unit on microcircuits using relays and thyristors.

Description of a simple control circuit for LED garlands.

The design of a simple timer that allows you to turn the load on and off at specified intervals. Working time and pause time do not depend on each other.

Description of the circuit and operating principle of a simple emergency lamp based on an energy-saving lamp.

A detailed story about the popular “laser-ironing” technology for manufacturing printed circuit boards, its features and nuances.

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 the exact values of 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 performance of digital integrated circuits, the need to supply a certain number of pulses to a device with visual control of processes, etc. Others generate sawtooth and rectangular pulses of various frequencies and duty cycles and amplitudes

Repair of various components and devices of low-frequency electronic equipment and technology can be significantly 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 rectangular pulses forms and simplification of 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 positive feedback (POF). 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. 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 tool is amateur radio circuits of 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

Since you have decided to become a self-taught electrician, then probably after a short period of time you will want to make some useful electrical appliance for your home, car or cottage with your own hands. At the same time, homemade products can be useful not only in everyday life, but also made for sale, for example. In fact, the process of assembling simple devices at home is not difficult at all. You just need to be able to read diagrams and use the ham radio tool.

As for the first point, before you start making electronic homemade products with your own hands, you need to learn how to read electrical circuits. In this case, ours will be a good helper.

Among the tools for novice electricians, you will need a soldering iron, a set of screwdrivers, pliers and a multimeter. To assemble some popular electrical appliances, you may even need a welding machine, but this is a rare case. By the way, in this section of the site we even described the same welding machine.

Special attention should be paid to available materials, from which every novice electrician can make basic electronic homemade products with their own hands. Most often, old domestic parts are used in the manufacture of simple and useful electrical appliances: transformers, amplifiers, wires, etc. In most cases, novice radio amateurs and electricians just need to look for all the necessary tools in a garage or shed in the country.

When everything is ready - the tools have been collected, spare parts have been found and minimal knowledge has been obtained, you can proceed to assembling amateur electronic homemade products at home. This is where our small guide will help you. Each instruction provided includes not only a detailed description of each stage of creating electrical appliances, but is also accompanied by photo examples, diagrams, as well as video lessons that clearly show the entire manufacturing process. If you do not understand some point, you can clarify it under the entry in the comments. Our specialists will try to advise you in a timely manner!