In general, controlling of the home appliances can be done by normal switches. But, these days we frequently see the home automation for controlling the appliances using several technologies. This article presents the DTMF based load control system. DTMF is a signaling system for recognizing the inputs on a keypad. It is used in signaling for telecommunication over analog telephone lines in the voice frequency band among telephone handsets and communication devices. This Article discusses about DTMF based load control system.
In nature, there are various electrical signals like analog, which means the time varying continuous signal. In such signals, the first quantity of the signal is a voltage, whereas the next quantity of the signal can be anything like pressure, force, temperature and light accelerations. Most of the microcontrollers available in the market are digital in nature. They can only recognize high or low-level input pins. For example, if the input is greater than 2.5 volts, then it will be treated as high, and if it is less than 2.5 volts, then it will be treated as low. So, we cannot directly measure voltage from microcontrollers. [Read more…]
The IC 555 timer was invented by “Signetic Corporation” and it was termed as SE or NE555 timer. Generally, it is a monolithic timing circuit that gives precise and highly stable delays of time or oscillation. These types of ICs are very cheap and reliable in cost when we compared with the OP-Amp applications in the same areas. These ICs are used as an astable and monostable multivibrators in digital logic probes, DC-DC converters, tachometers, analog frequency meters, voltage regulators, temperature controlled and measurement devices. The IC SE555 is used for where the temperature ranges from – 55°C to 125°C and the IC NE555 is used for where the temperature ranges from 0° to 70°C. [Read more…]
Nowadays, attend system in schools and colleges is generally based on paper. So sometimes this process causes errors and also takes more time. So this project uses RFID technology to make a note of every student entering into the classroom and also to calculate the time resides in the class. In this proposed system, every student is allotted with an RFID tag. The process of attendance can be done by placing the card near the RFID reader. This article discusses about what is RFID technology and attendance system using RFID with an example project.
This article discusses about some simple electronic circuits for beginners, which can be used in electronic circuits. These electronic circuits are used for simple electronic circuits projects, beginners, hobbyists and engineering students. The following simple circuits can be used as a mini project in engineering. But these circuits are not apt for final year projects. The following circuit comes under the category of the small, hobby, etc. These simple circuits are very essential for main projects. Because, major projects are designed with several combinations of electronic circuits. [Read more…]
The stethoscope is an electronic device used by the doctors in the medical field or in medical applications. This device is used to listen to the internal sound of a human body or an animal and BP in veins and arteries. Normally, stethoscope includes a round shaped resonator or chest piece and two tubes. Where, the resonator is placed on the chest and tubes are connected to the ears. These devices are also used for monitoring different small scale acoustic tasks and to check the scientific vacuum chambers.
The first audio amplifier was designed in the year 1909 by Lee De Forest when he developed the triode vacuum tube. The triode was a three terminal device with a control grid, which is used to modulate the electrons flow from the filament to the plate. This amplifier is mainly used to design the first AM radio. First audio amplifiers were based on valves which are called as vacuum tubes.But, present audio amplifiers are based on different types of transistors like FETSs, MOSFETs and BJTs. At present, there are still select valve sound and tube based amplifiers. In the year 1960, the audio amplifier which is based on transistors became hands-on with a low cost transistors in the wide range of availability. [Read more…]
Ultrasonic sound is a cyclic sound pressure with a high frequency than the upper limit of human hearing equal to 20KHz. Some animals like dolphins, mice, dogs, and bats have a high- frequency limit that is larger than that of the human ear & thus can hear ultrasound. This sound is very low in humans even at high intensities. Ultrasonic waves are found in wide industrial applications such as nondestructive testing of object is illuminated with ultrasonic waves and a repeat of the transmitted waves specifies a flaw, ball bearings, surgical instruments, Fine machine parts & several other objects can be cleaned ultrasonically. [Read more…]
In electronics, adder circuit performs addition of the binary numbers.in various computers and other types of processors. Adder circuits are not only used in ALUs, but also used in various processors to calculate increment or decrement operations, table indices, addresses, etc. A typical adder circuit generates sum and carry as the output. The main purpose of these addresses are used to add the different formats like XS-3, binary coded decimal (BCD) and gray code. When the one’s or two’s compliment are being used to specify negative numbers, it is small to alter adder to subtractor.A more complex adder is used to represent other signed numbers. The applications of adder circuit are, adder circuits are not only used to add binary numbers, but also used in digital applications such as address, table index, decoding and calculation etc. [Read more…]
Power electronics consist of various converter circuits such as AC to AC converter, AC to DC converter, DC to AC converter, cycloconverter, and so on. These converter circuits are frequently used in various electronic circuits and electronics projects for converting one form of electrical energy into another form of electrical another or electrical energy with different ratings in the same form. Here, in this article, let us discuss in detail about AC to AC converter circuit diagram and its working. But, primarily we must know what is an AC to AC converter. [Read more…]