MQ2 is a Gas sensor Module that can be used to sense gases like LPG (Cooking Gas), Smoke, Alcohol, Hydrogen, Methane, and Carbon Monoxide concentrations in air. This type of sensor is suitable in making projects like Air Quality monitoring systems, fire alarms, Gas Leakage detection, Alcohol detection-based Ignition system in vehicles, combining the same with IoT, the applications are infinite. In this tutorial let us dig deep into understanding how this sensor works and how we can use the same for making such projects.

The global 3D printing market size was valued at USD 13.78 billion in 2020 and is expected to expand at a compound annual growth rate of 21.0% from 2021 to 2028. With an ever-rising number of industries adopting 3D printing technologies in their regular design and development cycle, it is now apparent that 3D printing and other additive manufacturing techniques are no more just a prototyping technology but are a significant standard manufacturing technique. We now know that 3D printing and its services, directly or indirectly affect almost all scopes of manufacturing. …

3D printing allows you to manufacture a three-dimensional object from a digital 3D model. We feed a CAD model to the printer and it creates a fully functional 3D object. 3D printer slices each layer of the 3D model and then manufactures layer-by-layer, which finally results in a complete object. The 3D printer is of great use when it comes to the medical field, creating a prototype, and many other purposes.

The printers create objects from a variety of materials like molten plastic, powders, iron, etc. The 3D printed products created by the printer look exactly like the 3D model…

Modulation of a signal is a widely used phenomenon in telecommunication and electronics.

Going by the definition the Modulation, is a technique for impressing information (voice, music, picture, or data) on a radio-frequency carrier wave by varying one or more characteristics of the wave by the intelligence signal or the signal carrying the information.

It is typically the process of encoding information from a message source in a suitable way for transmission.

There are many types of Modulation, each designed to alter a specific characteristic of the carrier wave. …

Our world is filled with signals, the vibration due to the running of any motor or any audio/video signal. All of these real-world signals are analog signals and vary continuously concerning time.

An analog signal is a signal that is entirely free to vary its amplitude from -∞ to +∞ , i.e., it can take any value on the amplitude axis. At the same time, digital signals take discrete values on the amplitude axis, which is usually the Y-axis. The worldly examples of signals are mostly continuous time-type, meaning the signal has no break-point or is continuous throughout its life.

We know that in the PCB design, Impedance matching means that when the energy is transmitted, the load impedance must be equal to the Characteristic impedance of the transmission line.

Impedance matching in the transmission lines:

In a high-Frequency signal system, any cable or wire with a physical length more significant than the wavelength of a signal passing through this wire is called the transmission line. There are various transmission lines, such as coaxial cables, waveguides, microstrips, strip-lines, etc.

Whether it is about the digital or the analog signals, impedance matching between a source, the transmission line, and load is a must. The reason impedance matching…

Impedance matching is the process of simply making one impedance look like another. In high-frequency PCB design, Impedance matching means that when energy is transmitted, the load impedance must be equal to the transmission line’s Characteristic impedance.

Normally, it becomes necessary to match a load impedance to a driving source’s source or internal impedance.

Fig. 1: Message displayed when impedance matching is one of the issue

That’s where Impedance matching is playing its role. That message was displayed mostly because your laptop or smartphone’s input impedance did not match the device you were trying to connect, like a floppy disc or a pen drive.

The process for impedance matching in high-speed PCB…

In a general sense, transmission lines are electrical transmission lines connecting power supply of kilos of volts from the thermal generating station to distributors and consumers. However, there also exist transmission lines, which carry electricity of lower voltage and higher frequencies.

PCB Transmission Lines:

Fig 1: Printed Circuit Board

A PCB transmission line connects moving signals from their transmitters to their receivers on a printed circuit board (PCB). It has two main components — a signal trace and a return path for the ground, typically a ground plane. The space between the two components, more precisely conductors, is made up of the PCB dielectric material.

At higher frequencies…

Generally, a coordinate system is a system that uses one or more numbers, or coordinates, to locate the position of any point uniquely, line, place, or object concerning some reference system.

For example, the location of any place is obtained by placing its coordination on a map. That is what the global positioning system does since it is impossible to have a precisely defined address for each and everything in the world.

Types of Coordinate System:

The Coordinate system is a fundamental idea of defining the location in any system, and thus this system is altered according to the needs…


As the name suggests, a filter is a reactive network that freely passes the desired bands of frequencies while almost totally suppressing all other bands. Thus, a filter can extract desirable frequencies from signals that also contain undesirable or irrelevant frequencies. Filters are essential building blocks of any Electronic and Communication Systems. It is an important component in the frequency domain analysis of a signal.

Some prominent features are:

  • A filter is built from purely reactive elements.
  • It provides substantially constant transmission over the band, which they accept.
  • Ideally, Filter amends the relative amplitudes of the various frequency components and…


We are an electronics & robotics components supplier based out of Delhi, India. We also offer services such as 3D Printing, Modelling, PCB Designing & Assembly.

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