Those who are engaged in radio electronics at home are usually very inquisitive. Amateur radio circuits and homemade products will help you find a new direction in creativity. Perhaps someone will find an original solution to a particular problem. 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. More suitable for those who are just starting to tinker. If you have an old but working cell phone push-button telephone with the player's power button, you can make it, for example, door bell to your room. Benefits of this 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 fastened with screws or brackets, which are carefully bent. When disassembling, you will need to remember what goes for what, so that later you can reassemble everything.

The player's power button is soldered on the board, and two short wires are soldered instead. These wires are then glued to the board so as not to tear off the solder. The phone is going. It remains to connect the phone to the call button through a two-wire wire.

Homemade 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, given 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 intervene in without fear of damaging the car is the battery. If at the right time charging for the battery was not at hand, you can quickly assemble it yourself. This will require:

Ideal transformer for tube TV. Therefore, those who are fond of homemade electronics never throw away electrical appliances in the hope that they will someday be needed. Unfortunately, two types of transformers were used: with one and with two coils. To charge the battery at 6 volts, anyone will go, and for 12 volts, only with two.

The wrapping paper of such a transformer shows the winding leads, the voltage for each winding, and the operating current. For powering filaments electronic tubes a voltage of 6.3 V with a large current is used. The transformer can be redone by removing unnecessary secondary windings, or left as is. In this case, the primary and secondary windings are connected in series. Each primary is designed for a voltage of 127 V, therefore, by combining them, they get 220 V. The secondary ones are connected in series to get 12.6 V at the output.

Diodes must be capable of withstanding at least 10 A. Each diode requires a heat sink of at least 25 square centimeters. They are connected to a diode bridge. Any electrical insulating plate is suitable for fastening. A 0.5 A fuse is included in the primary circuit, and 10 A in the secondary circuit. The device does not tolerate a short circuit, therefore, when connecting the battery, the polarity must not be confused.

Simple heaters

In the cold season, it may be necessary to warm up the engine. If the car is parked where there is electricity, this problem can be solved with a heat gun. For its manufacture you will need:

• asbestos pipe;
• nichrome wire;
• fan;
• switch.

The diameter of the asbestos pipe is selected according to the size of the fan to be used. The performance of the heater will depend on its power. Pipe length is everyone's preference. Can be collected in it a heating element and fan, you can only heater. When choosing last version you will have to think about how to let the air flow to the heating element. This can be done, for example, by placing all components in a sealed enclosure.

Nichrome wire is also selected by 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. Bolts are used for fastening, which are inserted into pre-drilled holes in the pipe. The length of the spiral and their number are chosen empirically. It is desirable that the coil does not heat up red-hot when the fan is running.

The choice of fan will determine how much voltage you need to apply 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 through a cord with a plug, but it must have its own switch. It can be either just a toggle switch or an automatic one. The second option is more preferable, it allows you to protect common network. To do this, the tripping current of the machine must be less than the tripping current of the room machine. Still need a switch quick shutdown heater in case of malfunction, for example, if the fan does not work. Such a heater has its drawbacks:

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

Some problems can be solved by applying another homemade product. Instead of an asbestos pipe, you can use a coffee can. So that the spiral does not close 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 to the one who deals with them not only satisfaction, but also benefit. With their help, you can save electricity, for example, by turning off electrical appliances that you forgot to turn off. For this purpose, you can use a time relay.

The easiest way to create a timing element is to use the charge or discharge time of a capacitor through a resistor. Such a chain is included in the base of the transistor. The diagram will require the following details:

• high capacity electrolytic capacitor;
• transistor pnp 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. According to the selected relay, a transistor is selected, it is determined with what current and voltage it can work. 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 minus power supply. 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 supply through a variable resistor with a large 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 that 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 original 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 supply. As the capacitor charges, the base voltage begins to rise. At a certain voltage value, the transistor closes, de-energizing the relay. The relay disconnects the load. To make the circuit work again, you need to discharge the capacitor, for this the switch is switched.

Many electrical appliances can be repaired or made new with your own hands. For this house, there is always something that can be redone to perform new functions: old Digital Watch, baby car, disused computer and much more. Useful crafts can always be repaired or redone. For work it is better to have a workshop with tools.

Equipped home craftsman's workshop

power unit

Homemade electronic devices need different voltages. In particular, an adjustable power supply is needed for soldering. Such an opportunity can be provided by the LM-317 microcircuit, which is a voltage stabilizer.

Diagram of an adjustable power supply

Devices based on this scheme allow you to change output voltage within 1.2-30 V, using a variable resistor P1. The allowable current is 1.5 A, the power of the device depends on the choice of transformer.

Adjustment of the voltmeter is performed by a trimming resistor P2. To do this, set the current to 1 mA at an output voltage of the circuit of 30 V.

The more power is allocated on the microcircuit, the greater the difference between the input and output signals. To reduce heat, it requires a heatsink with a cooler.

A homemade board with an LM-317 chip is placed in a case - a computer power supply. A voltmeter and clamps to the output wires are installed on the front panel made of textolite.

Simple autoprobe

A probe for cars and other purposes should always be at hand at home, in the garage or on the road. The figure below shows a homemade scheme that allows you to check electrical circuits with a resistance of up to 10 kOhm and the presence of a voltage of 6-15 V.

The two indication circuits are connected in series to the battery and in parallel to each other. The first one consists of a resistor R1 and an LED HL1, which lights up when checking the voltage. At the same time, the battery is being charged.

Scheme and design: a) a homemade circuit that allows you to check electrical circuits with a resistance of up to 10 kOhm and the presence of a voltage of 6-15 V; b) self-made design of an autoprobe

When the circuit is being tested, current flows from the battery through circuit HL2, R2. At the same time, the HL2 LED lights up. Its brightness will be greater, the lower the resistance of the circuit.

Like all homemade products, a structural probe can be made different ways, for example, put it in a transparent plastic case, which is easy to glue with your own hands.

Such devices are indispensable when repairing an electrical network or a household appliance at home. Crafts can be more complex and have additional features.

Electric appliances for heat treatment of meat products without the use of fuel are made for a small number of servings and can be used at home or in the country. To prepare a shish kebab, with the help of an electric barbecue, there is no need to spend expensive watch rest, standing on the street at the barbecue.

In specialized stores, you can choose any device, but the price decides a lot. If you have the skills to handle electricity, it will be much cheaper to make an electric barbecue with your own hands.

Designs are made in horizontal or vertical design. The power of the device usually does not exceed 1.5 kW. The meat is heated using a spiral with a tungsten or nichrome filament. All metal parts are made of stainless steel.

Typical devices are vertical heaters in the center and skewers with the product around. They are attached to the top. It is advisable to make skewers in the form of spirals, from which the meat does not slip down during cooking.

Type of vertical electric grill

For high-quality cooking of a shish kebab with your own hands, skewers should be placed as close as possible to the heater, but so that the product does not touch the spiral. When placed at a distance, the meat will not fry, but will dry.

Pieces of the product, no larger than 40 mm in size, are mounted on a skewer, which is placed vertically around the heater. Then the electricity is turned on and the coil is heated.

The basis of the heater is a heat-resistant ceramic tube, on which a spiral is wound. Mounting at the bottom is done using a special cartridge.

In the round base, special cups are attached to collect fat and a frame that serves to hold the skewers vertically.

Cups are made from stainless steel. From below, they have cruciform protrusions, which are inserted into the slots of the base. Inside they have mounted devices for attaching skewers. Fixing the cup on both sides allows them to hold the skewers vertically.

The connection must be strong and at the same time easy to disassemble for cleaning. You can make a common removable tray for all skewers.

The cross section of the supply wire is selected according to the power of the heater (2.5 or 4 mm 2). At home or in the country, there should be a 16 A socket for it.

timer for watering plants

Devices with timers are used for drip irrigation of a site from a container at a certain time. They can be connected to valves with any capacity.

Often branded devices do not provide the required reliability. Then the old ones come to the rescue Wall Clock, which are serviceable, but are no longer used at home. Small magnets are attached to the ends of the minute and hour hands, and 3 reed switches on the dial.

Timer scheme for watering plants, in which a wall clock is applied

As soon as the hour hand reaches the number 7, and the minute hand reaches 12, which corresponds to the time of 7 hours, the reed switches SA1 and SA3 are triggered and the signal opens the solenoid valve. After 2 hours, the hands will move to 9 and 12, and the current through the contacts of the reed switches SA1 and SA2 will be supplied to close the valve.

The diagram shows a "rain sensor", which in wet weather closes the transistor VT1 and the valve remains permanently closed. Also provided manual control electrovalve through buttons S1 and S2.

The clock can be set to any time the valve is turned on.

Car with remote control

Homemade radio-controlled models capture not only children, but also adults. They can be used to play at home or arrange real competitions in the yard. To assemble with your own hands, you will need a chassis with wheels, an electric motor and a body.

There is a large assortment on sale, but first of all, you need to decide which machine is best to make. The control panel can be wired or radio controlled.

When choosing parts, you should pay attention to their quality. There should be no notches, inclusions and other mechanical defects on the plastic. The wheels are sold with the chassis and should turn easily. Grip with the surface is better provided by rubber. Plastic wheels in this regard are much worse.

It is better for a beginner to take an electric motor, which is cheaper and easier to maintain than an internal combustion engine. You can choose any case or make according to your sketch.

The motor, battery and radio unit with antenna are mounted on the chassis of a mini-car. If a kit with accessories is purchased, assembly instructions are included with it.

After installing the parts, the operation of the motor is regulated. The body on the chassis is installed after everything works.

You can assemble mini-copies at home as follows:

• the car is assembled carefully and by common efforts;
• materials of parts of the model may differ from the original;
• small and insignificant details can be omitted.

The model can be made without looping on a certain brand of car. Much depends on finances and the availability of free time. Assembling a mini-car at home with a child is of great educational value.

Work on assembling the car model is carried out according to plan. Some parts need to be bought, but old toys can be used.

The motor must match the weight of the device in terms of power. Fresh batteries or accumulators are used for power.

If you use a special autoconstructor, crafts can be very diverse. Assembly sequence:

• the frame is assembled first;
• the motor is mounted and adjusted;
• a power supply is installed;
• an antenna with a radio unit is fixed;
• wheels are installed and adjusted.

Types of radio-controlled car models

Many homemade tricks are revealed in this video.

Electronic homemade products can make life more comfortable and save a lot of money. In addition, you can find a use for old electrical appliances so that they do not gather dust in the pantry without a purpose. Useful do-it-yourself crafts often turn out to be better than factory-made products.

Every day it becomes more and more, there are many new articles, it is rather difficult for new visitors to immediately orient themselves and revise everything already written and previously posted at once.

I really want to draw the attention of all visitors to individual articles that were posted on the site earlier. In order not to have to look for a long time necessary information I will make several "entry pages" with links to the most interesting and useful articles on selected topics.

We will name the first such page "Useful electronic homemade". Here we consider simple electronic circuits, which are available for implementation to people of any level of training. The schemes are built using a modern electronic database.

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

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

The modern element base of electronics greatly simplifies circuitry. Even an ordinary 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 presents several schemes of apparatus for spot welding.

With the help of the described design, it is possible to determine whether a mechanism located in another room or building is working or not. The information about the work 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 simple device, disconnecting the load in the event of an output mains voltage beyond the allowed limits.

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

An article on how to make a lamp soft start device using the KR1182PM1 chip.

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

An article about what can replace the mechanical thermostat of an oil heating radiator.

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

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

Article about various ways connecting the load to the control unit on microcircuits using relays and thyristors.

Description of a simple scheme for controlling LED garlands.

The design of a simple timer that allows you to turn on and off the load at specified intervals. Working time and pause time are independent of each other.

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

A detailed story about the popular "laser-iron" manufacturing technology printed circuit boards, its features and nuances.

For those who are just starting to take their first steps in electronics, it is important to start somewhere. Well, here are some ideas that might come in handy in the future and give you an idea of ​​how things should be done at the same time. What to choose if you want to make simple ones with your own hands? Here are options that can be used in everyday life.

Simple power control for smooth turning on of lamps

This type of device is widely used. The simplest is a conventional diode that is connected in series with the load. Such regulation can be used to extend the life of the incandescent lamp, as well as to prevent overheating of the soldering iron. They can also be used to change power over a wide range of values. First, there will be the simplest do-it-yourself electronic homemade products. You can see the diagrams here.

How to protect yourself from mains voltage fluctuations

This device disconnects the load if the mains voltage is out of range. As a rule, a deviation of up to 10% from the standard is considered within the normal range. But due to the peculiarities of the energy supply system in our country, such frameworks are not always respected. So, the voltage can be 1.5 times higher, or much lower than necessary. The result is often unpleasant - the equipment fails. Therefore, there is a need for a device that will turn off the load before something has time to burn out. But when creating such a homemade product, you must be careful, since the work will be carried out with considerable stress.

How to make a safety transformer

Transformerless power supplies are often used in various electronic designs. Typically, such devices have low power, and to avoid electrical shock, they are placed in an insulating plastic case. But sometimes they need to be configured, and then the protection is opened. To avoid possible injury, a safety isolation transformer is used. It will also be useful in the repair of such devices. Structurally, they consist of two identical windings, each of which is designed for the network. As a rule, the power of transformers of this type ranges from 60-100 W, these are the optimal parameters for setting up various electronics.

Simple emergency light source

What to do if it is necessary that in the event of a power outage, the illumination of some area is maintained? The answer to such challenges can be an emergency luminaire, made on the basis of a standard energy-saving lamp, the power of which does not exceed 11 watts. So if it is necessary that the light be somewhere in the corridor, utility room or workplace, this homemade product will come in handy. Usually, when voltage is present, they operate directly from the network. When it disappears, the lamp starts to function on battery power. When the mains voltage is restored, the lamp will work and the battery will automatically charge. The best do-it-yourself electronic homemade products were left at the end of the article.

Soldering iron boost controller

In cases where it is necessary to solder massive parts or the mains voltage often drops, the use of a soldering iron becomes problematic. And a step-up power regulator can help out of this situation. In these cases, the load (i.e. soldering iron) is powered by a rectified mains voltage. The change is carried out using an electrolytic capacitor, the capacity of which allows you to get a voltage of more than 1.41 network. So, with a standard voltage value of 220 V, it will give 310 V. And if there is a drop, say, to 160 V, it turns out that 160 * 1.41 \u003d 225.6 V, which will allow you to operate optimally. But this is just an example. You have the opportunity to make a scheme suitable specifically for your conditions.

The simplest twilight switch (photo relay)

As new parts are created, fewer and fewer components are now needed to make some kind of device. So, for a conventional twilight switch, only 3 of them are needed. Moreover, due to the versatility of the design, multi-purpose use is also possible: in apartment building; to illuminate the porch or courtyard of a private dwelling, or even a separate room. Pointing to the features of such a design as a twilight switch, they also call it a “photo relay”. You can find many implementation schemes that were made either by amateurs or industrialists. They have their own set of positive and negative properties. As negative properties, either the need for a constant voltage source, or the complexity of the circuit itself is usually called. Also, when buying cheap and simple parts or whole sets, they often complain that they simply burn. The functionality of the scheme is based on three components:

1. Photocell. It is usually understood as photoresistors, phototransistors and photodiodes.
2. Comparator.
3. Triac, or relay.

When there is daylight, the resistance of the photocell is small, and does not exceed the response threshold. But as soon as it gets dark, the construction will be turned on at the same moment.

Conclusion

Here are some interesting do-it-yourself electronic homemade products you can do. The main thing in cases where something does not work out is to keep trying, and then everything will work out. And as you gain experience, you can move on to more complex schemes.

So. Life has turned out so that I have a house in the village with gas heating. You can't live there permanently. The house is used as a summer cottage. A couple of winters stupidly left the boiler on with a minimum coolant temperature.
But there are two downsides.
1. Gas bills are astronomical.
2. If there is a need to come to the house in the middle of winter, the temperature in the house is around 12 degrees.
Therefore, something had to be invented.
I'll clarify right away. Presence of a point WI-FI access within the range of the relay is mandatory. But, I think, if you get confused, you can put a connected mobile phone next to the sensor and give out a signal from the phone.

Do-it-yourself motion sensor connection 4 pins diagram

Do-it-yourself motion sensor connection diagram

It happens that you need to install lighting in the country, or in the house, which will be triggered when moving or a person or someone else.

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

In this article I tell you how to connect such a sensor if it does not have 3 contacts, but 4 like this one.

Do-it-yourself 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 smooth adjustment variable resistor fan speed.

The floor fan speed controller circuit came out the simplest. To fit into the case from the old charge Nokia phone. There also climbed the terminals from a conventional electrical outlet.

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

DIY lighting for plants

DIY lighting for plants

There is a problem with the lack of lighting. plants, flowers or seedlings, and there is a need for artificial light for them, and this is the light we can provide DIY LEDs.

DIY brightness control

DIY brightness control

It all started with the fact that after I installed at home halogen lamps for lighting. When turned on, they often burned out. Sometimes even 1 bulb a day. Therefore, I decided to make a smooth turn-on of lighting based on a dimmer with my own hands, and I am attaching a dimmer circuit.

Do-it-yourself refrigerator thermostat

Do-it-yourself refrigerator thermostat

It all started with the fact that after returning from work and opening the refrigerator found it warm. Turning the thermostat knob did not help - the cold did not appear. So I decided not to buy. new block, which is also rare, but do it yourself electronic thermostat on ATtiny85. With the original thermostat, the difference 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 on or the temperature is above the upper threshold.

DIY soil moisture sensor

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 by which you can 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 90mA, which is quite enough, turn on the relay.

Also suitable for automatic start drip irrigation to avoid excess moisture.

Fluorescent lamp power circuit

Power supply circuit for a fluorescent lamp.

Often on failure energy-saving lamps, it burns power plan, and not the lamp itself. As is known, LDS with burned-out filaments, it is necessary to feed the mains with rectified current using a starterless starting device. In this case, the filaments of the lamp are shunted by a jumper and to which high voltage to turn on the lamp. There is an instantaneous cold ignition of the lamp, a sharp increase in voltage on it, when starting without preheating the electrodes. In this article, we will look at do-it-yourself LDS lamp start.

USB keyboard for tablet

USB keyboard for tablet

Somehow, suddenly, I took something and decided to buy it for my PC new keyboard. The desire for novelty is unstoppable. Changed the background color from white to black, and the color of the letters from red - black to white. A week later, the desire for novelty naturally went away like water in the 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, did not even imagine that it would happen so quickly. And therefore the name would be even better suited not which is, but how to connect usb keyboard to tablet