To create a home weather station or thermometer, you need to learn how to pair the Arduino board and a device for measuring temperature and humidity. Temperature measurement can be dealt with using a thermistor or a digital sensor DS18B20, but for measuring humidity use more complex devices - sensors DHT11 or DHT22. In this article, we’ll show you how to measure temperature and humidity using the Arduino and these sensors.

The easiest way to determine the temperature is to use a thermistor. This is a type of resistor whose resistance depends on the ambient temperature. There are thermistors with a positive and negative temperature coefficient of resistance - PTC (also called posistors) and NTC thermistors, respectively. In the graph below you see the temperature dependence of resistance. The dashed line shows the dependence ...

Most electrical installations are always earthed using a special ground wire. The ground wire is designed to connect the conductive elements of the installation to the ground, which initially has zero potential, and thereby create a safe zero potential on the grounding element. The main purpose of the ground wire is to protect a person from electric shock if the phase voltage supplying the unit for some reason gets on its case.

An example is a washing machine, in the wiring of which the insulation is damaged over time and the bare phase wire at some point touches its metal case of a household appliance. In this case, a person is at risk, because if he touches the car’s body, he will get an electric shock, because current will flow through his body in the direction of the earth, but the person is practically on the floor, which is not always securely isolated ...

A sound or noise sensor is usually used in conjunction with fixtures, so that when popping, the sound of voice or steps, or simply in the presence of noise, light is lit in the room. The light can be turned on and stayed on constantly, or for a limited period of time, or for as long as the sensor “hears” steps, noise, or voice, that is, while at least one person is walking around the room, equipment is working, or someone is talking .

This solution can not only reduce lighting costs, it also provides a flexible and convenient automated approach to controlling the on and off lights. Sound (noise) sensors are distinguished by the ability to adjust the sensitivity of the microphone, therefore, they enable the user to make fine adjustments to a certain volume (recognized as a signal to action) of sound. Sensors working on this principle appeared at the end ...

To begin with, we will understand the differences between RCDs from the difavtomat, because outwardly they are very similar, although they differ in their functions. RCD - residual current device. It opens the circuit into which it is connected when a leakage current to the earth occurs, that is, at the moment when a differential current of a certain value begins to be present in the network, caused for example by damage to the wiring insulation or the contact of a living being with a current-carrying structure.

The bottom line is that a person can get an electric shock from the leakage current if he accidentally comes into contact with damaged equipment.In addition, the leakage current contributes to overheating of the wiring, which can lead to a fire. For this reason, RCDs are used to protect wiring and people in the event of a leakage current, measured in milliamps. A differential circuit breaker, unlike an RCD, combines the functions of an RCD and a circuit breaker ...

The oscilloscope is the eyes of a master repairing electronics and a radio amateur. But the cost of advanced models is incomprehensible for beginners and even for many experienced craftsmen. For example, not the coolest digital oscilloscope UNI-T UTD2025CL with two channels with the ability to transmit signals with a frequency of up to 25 MHz costs more than $ 200, and some RIGOL MSO2302A-S is a powerful two-channel oscilloscope with two channels and a bandwidth of 300 MHz with a recorder function costs almost $ 4,000.

But where to go to the simple peasant? For starters, you can turn to the products of manufacturers from the Middle Kingdom. There are a lot of portable oscilloscopes on Aliexpress with different characteristics and capabilities, we will consider some of them in this article. To begin with, if we talk about portable oscilloscopes, then in almost all cases these are digital devices. Like any measuring device, oscilloscopes have a number of characteristics ...

Sometimes many of us have to deal with the problem of a breakdown or accidental breakage of the connector from the Internet cable. As such a cable, a twisted pair cable is used today, consisting, as a rule, of four pairs of twisted copper conductors having an individual color marking of insulation.

A twisted pair cable is traditionally used to transfer signals between a router or modem and a computer, or simply between computers, since it is ideal for this, and to a sufficient extent allows you to prevent interference from various external sources to the transmitted signal. Let’s talk about how to squeeze a couple correctly, how to properly attach a new connector to it. Violation of the health of the connector is a frequent phenomenon. We transfer modems and routers, make a rearrangement in the apartment, rearrange the computer, accidentally touch the loose cable with our foot ...

To connect various household appliances, industrial equipment or just gadgets for charging to the AC mains, we are used to using wall outlets. If a household outlet meets the specifications of all our requirements, then this is very good, such an outlet becomes our favorite outlet for powering a particular device, and we get used to powered this device from it. The outlet is in a suitable place, at a convenient height, the plug sits comfortably in it, maybe there is a backlight, etc.

A favorite outlet can become quite easy, because today many manufacturers produce them using various materials. At a minimum, outlets are overhead, recessed, or even hidden. In addition, sockets may have additional useful features that will increase comfort and provide additional reliability for using this socket for its intended purpose in a selected location ...

It happens that some time after the installation of the electric stove, it begins to “bite” its owner, that is, for some reason, its body begins to be shocked. It can be very gentle strokes, but pleasant, of course, is not enough, especially if you touch the stove with wet hands.

This problem must be eliminated as soon as the first symptoms appear, otherwise the matter can reach serious and life-threatening injuries.It is impossible to name one single reason here, therefore, a diagnosis should be made and the root of the malfunction should be correctly identified in order to eliminate it later. If you are more or less versed in the device of the electric stove and have basic skills in handling a multimeter and an indicator screwdriver, then in principle a simple diagnosis will be affordable. However, it is important to remember that any repair operations with electrical appliances promise a danger if a person does not have experience and qualifications ...