Learn Electronics

         The word ‘Laser’ is an acronym for light amplification by stimulated emission of radiation. The laser is a source of highly directional , monochromatic & coherent light. Monochromatic light is single - wavelength light or practically a very narrow band of wavelengths.           Laser light has spatial & temporal coherence. The spatial coherence means that the two different points of a wavefront of a given radiation have constant phase difference.

Communication   - Communication is the process of establishing connection or link between two points for information exchange.Typical examples of communication system are mobile communication, radar communication, television broadcasting, radio telephony, line telephony, etc. Communication system  - Communication system is to transmit an information bearing signal, from a source, located at one point, to a user or destination located at another point some distance away. The essential component of a communication system are information source, input transducer, transmitter, communication channel, receiver & output transducer.These functional elements are represented by blocks.   (1) Information Source  - A communication system serves to communicate a message or information. This message or information originates in the information source. There can be various message in the form of word, group of words, code, symbols, sound, signal etc. (2) Input ...

Capacitor is a passive component that has the ability to store the energy in the form potential difference between two plates. which form to be positive & negative depending upon the direction of charge storage .   Symbol &Unit   - The capacitor symbol is represented by drawing two parallel lines close to each other, but not touching. It consists of two terminals. Standard units for capacitor is Farads. The most common subunits of capacitance are micro farad, nano farad (nF), pico farad (pF) & femo farad(fF) etc.  1 micro farad = 10–⁶ farads 1 nano farad = 10–⁹ farads 1 pico farad = 10–¹² farads 1 femo farad = 10–¹⁵ farads Construction of capacitor  - A capacitor has the  ability to store electric energy in the form of electric field. A non conducting region is present between two plates which is called as dielectric material   (Insulator such as aluminum, paper,air,& ceramic etc). When two plates having same are...

Resist is the word which means to "oppose". Resistor is a passive electrical component which has the property of oppose the electric current  & the property of opposing the flow of electron, is called resistance. Resistor are used for many purposes, a few examples include delimit electric current, voltage division, heat generation,matching & loading circuits, control gain, & fix time constant. Symbol & Units - The symbol for a resistor is as shown below. The units of resistance is ohms, which is indicated by omega. The formula for resistance is  Connecting Resistors - A resistor when connected in a circuit, that connected can be either series or parallel. Resistors in series - When n fixed resistors connected in series.The current I flowing through each resistor is the same in the series circuit, because there is only one path for the current to flow.  The total equivalent resistance of the series circuit is equal to the ...

We can explain, atom structure from these atomic model theories ( 1) Thomson's Atomic Model  - J.J.Thomson gave the first idea regarding structure of atom. According to this model. • An atom is a solid sphere in which entire & positive charge. It's mass is uniformly distributed in which negative charge (electron) are embedded like seeds in watermelon.   • This model explained successfully the phenomenon of thermionic emission, ionisation & photoelectric emission. Failure of Thomson's Atomic Model  -   • Thomson's atomic model fail to explain the scattering of alfa - particles & it can't explain the origin of spectral lines observed in the spectrum of hydrogen & other atom. ( 2) Rutherford's Atomic Model  - Rutherford's atomic  model bassed on alfa - particles scattering experiment. • Most of the mass & all of the charge af on atom concentrated in a very small region is called atomic nucleus. • Nucleus is ...

Complementary Metal Oxide semiconductoris a type of transistor fabrication process that uses complementary & symmetrical pairs of P-type & N-type MOSFET for logic functions . Generally,the CMOS technology is associated with VLSI (Very Large Scale Integrated) circuit,where a few million or even billions of transistors (MOSFETs to be specific) are integrated into a single chip or die. The reasons for the dominant use of CMOS technology in the fabrication of VLSI chips are reliability, low power consumption, considerably low cost & most important scalability . These are four important CMOS process technology (1) N- well process  - In the N-well process,an N-type well or tub is diffused in the P-type substrate. The PMOS transistor M2 is fabricated within this well. The well region acts as the substrate for the PMOS transistor.The additional processing step are the formation on N-region & the ion-imlantation step of P-type source & drain regions.A typical CMOS inver...

Metal-Oxide semiconductor field effect transistor (MOSFET) has an oxide layer between gate & channel to increase the input impedance & reduce the overall circuit current. The extraordinarily high input impedance means that these circuits are able to consume very low power levels. Principal of MOSFET  - By applying a transverse electric field across an insulator (oxide layer), deposited on the semiconducting material, the thickness & hence the resistance of a conducting channel of a semiconducting material can be controlled. Classification of MOSFET  - MOSFET is classified in two types. P-ch = P channel           N-ch = N channel  Construction of MOSFET  -  MOSFET is a four terminal device having source(S), gate(G), Drain(D), & body substrate (B) terminals. An oxide layer is deposited on the substrate to which the gate terminal is connected. The oxide layer act as a insulator. ...

 A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction,to direct current (DC),which flows in only one direction.This process is known as rectification. Types of rectifier  - There are mainly three types of rectifier. ( 1) Half wave rectifier  - A type of rectifier that converts only the half cycle of the alternative current (AC) into direct current (DC) is known as half wave rectifier & only require a single diode to construct.   A high AC voltage is applied to the primary side of the step down transformer & it will get a low voltage, which will be applied to the diode. During the positive half cycle of the AC voltage,the diode will be forward biased, for an ideal diode, the forward voltage drop is zero.So the whole input voltage will appear across the load resistance. During the negative half cycle of the AC voltage,the diode will be reverse biased ...