So. Life has turned out in such a way that I have a house in the village with gas heating. It is not possible to live there permanently. The house is used as a summer house. For a couple of winters I stupidly left the boiler on with the minimum coolant temperature.
But there are two disadvantages.
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, it was necessary to invent something.
I'll clarify right away. The presence of a WI-FI access point in the relay coverage area 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.

Connecting a 4-pin motion sensor with your own hands (diagram)

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 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.

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.

One of the common hobbies of amateurs and professionals in the field of electronics is the design and manufacture of various homemade products for the home. Electronic homemade products do not require large material and financial costs and can be done at home, since work with electronics is, for the most part, “clean”. The only exception is the manufacture of various body parts and other mechanical components.

Useful electronic homemade products can be used in all areas of everyday life, from the kitchen to the garage, where many are engaged in improving and repairing car electronic devices.

Homemade products in the kitchen

Kitchen electronics crafts can be a complement to existing accessories and fixtures. Industrial and homemade electric kebab makers are very popular among apartment residents.

Another common example of kitchen homemade products made by a home electrician is timers and automatic switching on of lights above work surfaces, and electric ignition of gas burners.

Important! Changing the design of some household appliances, especially gas appliances, may cause “misunderstanding and rejection” by regulatory organizations. In addition, it requires great care and attention.

Electronics in the car

Homemade devices for cars are most widely used among owners of domestic brands of vehicles, which are distinguished by a minimal number of additional functions. The following schemes are in wide demand:

Sound indicators for turns and handbrake;
Battery and generator operating mode indicator.

More experienced radio amateurs are equipping their cars with parking sensors, electronic window drives, and automatic light sensors to control low beam headlights.

Homemade crafts for beginners

Most novice radio amateurs are engaged in the manufacture of structures that do not require high qualifications. Simple proven designs can serve for a long time and not only for the sake of benefit, but also as a reminder of the technical “growing up” from a beginner radio amateur to a professional.

For inexperienced hobbyists, many manufacturers produce ready-made construction kits that contain a printed circuit board and a set of elements. Such sets allow you to practice the following skills:

Reading schematic and wiring diagrams;
Correct soldering;
Setup and adjustment using a ready-made method.

Among the sets, electronic watches of various designs and degrees of complexity are very common.

As an area of application of knowledge and experience, radio amateurs can design electronic toys using simpler circuits or modifying industrial designs to suit their wishes and capabilities.

Interesting ideas for crafts can be seen in the examples of making radio-electronic crafts from worn-out computer parts.

Home workshop

To independently design radio-electronic devices, you need a certain minimum of tools, devices and measuring instruments:

Soldering iron;
Side cutters;
Tweezers;
Screwdriver Set;
Pliers;
Multifunctional tester (avometer).

On a note. When planning to do electronics yourself, you should not immediately take on complex designs and purchase an expensive tool.

Most radio amateurs began their journey by using a simple 220V 25-40W soldering iron, and the most popular Soviet tester, the Ts-20, was used in the home laboratory. All this is enough for practicing with electricity, acquiring the necessary skills and experience.

There is no point in buying an expensive soldering station for a novice radio amateur if he does not have the necessary experience with a conventional soldering iron. Moreover, the possibility of using the station will not appear soon, but only after sometimes quite a long time.

There is also no need for professional measuring equipment. The only serious device that even a novice amateur may need is an oscilloscope. For those who already understand electronics, an oscilloscope is one of the most sought-after measurement tools.

Inexpensive digital devices made in China can be successfully used as an avometer. Having rich functionality, they have high measurement accuracy, ease of use and, importantly, have a built-in module for measuring transistor parameters.

When talking about a DIY home workshop, one cannot fail to mention the materials used for soldering. This is solder and flux. The most common solder is POS-60 alloy, which has a low melting point and provides high soldering reliability. Most solders used for soldering all kinds of devices are analogues of the mentioned alloy and can be successfully replaced with it.

Ordinary rosin is used as a flux for soldering, but for ease of use it is better to use its solution in ethyl alcohol. Rosin-based fluxes do not require removal from installation after operation, since they are chemically neutral under most operating conditions, and the thin film of rosin formed after evaporation of the solvent (alcohol) exhibits good protective properties.

Important! When soldering electronic components, active fluxes should never be used. This is especially true for soldering acid (zinc chloride solution), since even under normal conditions such flux has a destructive effect on thin copper printed conductors.

To service heavily oxidized terminals, it is better to use active acid-free flux LTI-120, which does not require rinsing.

It is very convenient to work using solder that contains flux. The solder is made in the form of a thin tube, inside of which there is rosin.

For mounting elements, breadboards made of double-sided foil fiberglass, which are produced in a wide range, are well suited.

Security measures

Working with electricity is associated with risks to health and even life, especially if the electronics are designed with your own hands with mains power. Homemade electrical devices should not use transformerless power from a household AC network. As a last resort, such devices should be configured by connecting them to the network through an isolation transformer with a transformation ratio equal to unity. The voltage at its output will correspond to the network voltage, but at the same time reliable galvanic isolation will be ensured.

Many electrical appliances can be repaired or new ones can be made with your own hands. For this home, there will always be something that can be converted to perform new functions: an old electronic watch, a children's car, an out-of-use computer and much more. Useful crafts can always be repaired or remade. It is better to have a workshop with tools for work.

Equipped master's home workshop

power unit

Homemade electronic devices require different voltages. In particular, soldering requires a regulated power supply. This opportunity can be provided by the LM-317 chip, which is a voltage stabilizer.

Regulated power supply circuit

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

The voltmeter is adjusted using trimming resistor P2. To do this, set the current to 1 mA at a circuit output voltage of 30 V.

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

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

Simple auto tester

A sampler for cars and other purposes should always be on hand at home, in the garage or on the go. The figure below shows 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.

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

Circuit and design: a) homemade circuit, which 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) homemade design of a test probe

When a circuit is 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 circuit resistance.

Like all homemade products, the tester can be constructed in different ways, for example, by placing it in a transparent plastic case, which is easy to glue together with your own hands.

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

Electric devices for heat treatment of meat products without the use of fuel are made for a small number of portions and can be used at home or in the country. To prepare barbecue using an electric barbecue maker, there is no need to spend expensive hours of rest standing outside at the barbecue.

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

The structures 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 thread. All metal parts are made of stainless steel.

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

Vertical type of electric kebab maker

To make high-quality barbecue with your own hands, the 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 out.

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

The heater is based on a heat-resistant ceramic tube on which a spiral is wound. Fastening at the bottom is done using a special cartridge.

In the round base there are special cups for collecting fat and a frame that serves to hold the skewers vertically.

Cups are made of stainless steel. They have cross-shaped protrusions at the bottom, which are inserted into the slots in the base. Inside they have 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 to match the power of the heater (2.5 or 4 mm2). 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 an area 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 an old wall clock comes to the rescue, which is in working order, but is no longer used at home. Small magnets are attached to the ends of the minute and hour hands, and there are 3 reed switches on the dial.

Timer circuit for watering plants, which uses a wall clock

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

The diagram shows a “rain sensor”, which in wet weather closes transistor VT1 and the valve remains constantly closed. Manual control of the solenoid valve is also provided via 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 captivate not only children, but also adults. They can be used for playing at home or for real competitions in the yard. To assemble it yourself, you will need a chassis with wheels, an electric motor and a housing.

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. The plastic should be free of nicks, inclusions and other mechanical defects. The wheels are sold with the chassis and should turn easily. Grip on the surface is better provided by rubber. Plastic wheels are much worse in this regard.

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

The motor, battery and radio unit with antenna are installed on the chassis of the mini-car. If you purchase a kit with components, assembly instructions are included.

After installing the parts, the operation of the motor is adjusted. The housing is installed on the chassis after everything is working.

You can assemble mini-copies at home as follows:

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

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

The work on assembling the car model is carried out according to plan. Some parts need to be purchased, but you can use old toys.

The power of the motor must match the weight of the device. Fresh batteries or accumulator are used for power supply.

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

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

Types of radio-controlled car models

Many DIY 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 DIY crafts are often better than factory-made products.

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