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 minimum temperature coolant.
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.
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.
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.
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.
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. So I decided not to buy new block, which is also rare, and make an electronic thermostat yourself on 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 conservatories, 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.
Also suitable for automatic switching on drip irrigation to avoid excess moisture.
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 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.
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.
Nowadays, there is a huge selection of tools and devices for practicing radio electronics: soldering stations, stabilized laboratory power supplies, engraving kits (for drilling boards and processing construction materials), tools for stripping and processing wires and cables, and so on. And all this equipment costs a lot of money. A reasonable question arises: will a novice radio amateur be able to purchase this entire arsenal of equipment? The answer is obvious, especially for some people who are interested in electronics on occasion (for the individual production of some useful devices for household purposes), the purchase of such a quantity of tools is not required. The way out of this situation is quite simple - make necessary tool with my own hands. These homemade products will serve as a temporary (and for some, permanent) alternative to factory equipment.
So let's get started. The basis of our device is a network step-down transformer from any old radio-electronic device (TV, tape recorder, stationary radio, etc.). The power cord, fuse block and power switch may also come in handy.
Next, we need to equip our power supply with an adjustable voltage stabilizer. Since the design is designed to be repeated by beginning radio amateurs, the most rational, in my opinion, would be to use an integrated stabilizer on a microcircuit like LM317T (K142EN12A). Based on this microcircuit, we will assemble an adjustable voltage stabilizer from 1.2 to 30 volts with a full load current of up to 1.5 amperes and protection against overcurrent and overtemperature. Schematic diagram stabilizer is shown in the figure.
You can assemble the stabilizer circuit on a piece of non-foil fiberglass (or electrical cardboard) hinged installation or on a breadboard - the circuit is so simple that it doesn't even require a printed circuit board.
A voltmeter can be connected to the output of the stabilizer (in parallel with the terminals) to monitor and adjust the output voltage, and (in series with the positive terminal) a milliammeter to monitor the current consumption of the amateur radio homemade product connected to the stabilizer.
Another necessary thing in the arsenal of a beginning radio amateur is a microelectric drill. As you know, in the arsenal of any (beginner or experienced) home-made worker there is a “warehouse” of obsolete or faulty equipment. It would be good if in such a “warehouse” there is a children’s car with an electric drive, the micromotor from which will serve as an electric motor for our microdrill. You just need to measure the diameter of the motor shaft and purchase a cartridge with a set of collet clamps (for drills of different diameters) for this micromotor at the nearest radio store. The resulting micro drill can be connected to our power supply. By adjusting the voltage, you can regulate the number of revolutions of the drill.
Next necessary thing— low-voltage soldering iron with galvanic isolation from the network (for soldering field-effect transistors and microcircuits that are afraid of static discharge). Low-voltage soldering irons for 6, 12, 24, 48 volts are available for sale, and if the transformer that we chose for our product is from an old tube TV, then we can consider ourselves very lucky - we already have a ready-made winding for powering a low-voltage electric soldering iron (you should use filament windings (6 volts) of the transformer for powering the soldering iron). The use of a transformer from a tube TV gives another advantage to our circuit - we can also equip our device with a tool for stripping the ends of the wire.
The basis of this device is two contact blocks, between which a nichrome wire and a button with normally open contacts. The technical design of this device can be seen from the figure. It is connected to the same filament winding of the transformer. When you press the button, the nichrome heats up (everyone probably remembers what a burner is) and burns through the wire insulation in the right place.
The housing for this power supply can be found ready-made or assembled yourself. If you make it from metal and provide ventilation holes only on the bottom and sides, then on top you can place stands for a soldering iron and wire stripping tool. Switching of this entire equipment can be done using a packet switch, a system of toggle switches or connectors - there are no limits to imagination here.
However, you can modernize this block to suit your needs - supplement, for example, charger for batteries or electric spark engraver, etc. This device served me for many years and still serves (though now at the dacha) for the manufacture and testing of various radio-electronic and electrical homemade products. Author: Elektrodych.
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 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 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 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, winding a coil is difficult, 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. Humans do not have sense organs that allow them to see. electricity, 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
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.
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.
Homemade devices for cars are most widely used among owners of domestic brands of vehicles, which are distinguished by a minimum number of additional functions. The following schemes are in wide demand:
More experienced radio amateurs are equipping their cars with parking sensors, electronic window lifters, automatic sensors illumination to control the low beam headlights.
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 printed circuit board and a set of elements. Such sets allow you to practice the following skills:
Very common among sets Digital Watch various options execution and degree of complexity.
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.
For self-design radio-electronic devices require a certain minimum of tools, devices and measuring instruments :
On a note. When planning to do electronics with your own hands, 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 can be successfully used as an avometer. made in China. Having rich functionality, they have high accuracy measurements, 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. Especially it concerns 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.
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 network alternating current. 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.
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 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 push-button telephone 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.
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.
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.
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:
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 last 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 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 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:
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:
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 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.
