electronics
by
webmaster
Electrical components in an electronic system is physical entity that mainly affects the even minor electrons or any of its associated areas in the most efficient and desire manner to undertake some intended functions. Mathematical methods form vital part in the study of electronics.
Making the Decision to Buy Noise Canceling Headphones
by
Christine Peppler
Do you ever find yourself turning up the volume on your MP3 player or other portable device to drown out the noise around you in a crowd or on an airplane? Do you feel tired after being in a noisy environment for an extended period of time? Maybe it's time to consider noise canceling headphones. Here are the basics to help you decide.
GPRS - General Packet Radio Service
by
Muhammad Wasiq Ansari
General Packet Radio Service (GPRS) is a mobile data service available to users of GSM mobile phones. It is often described as "2.5G", that is, a technology between the second (2G) and third (3G) generations of mobile telephony. It provides moderate speed data transfer, by using unused TDMA channels in the GSM network.
The Field of ELECTRONICS.
by
Muhammad Wasiq Ansari
The field of
Electronics comprises the study and use of systems that operate by controlling the flow of electrons (or other charge carriers) in devices such as thermionic valves (vacuum tubes) and semiconductors. The design and construction of electronic circuits to solve practical problems is an integral technique in the field of electronic
Laser Diodes
by
James
The laser diode is a further development upon the regular light-emitting diode, or LED. The term "laser" itself is actually an acronym, despite the fact it's often written in lower-case letters. "Laser" stands for Light Amplification by Stimulated Emission of Radiation, and refers to another strange quantum process whereby characteristic light emit
Light-emitting Diodes (L.E.D)
by
James
Diodes, like all semiconductor devices, are governed by the principles described in quantum physics. One of these principles is the emission of specific-frequency radiant energy whenever electrons fall from a higher energy level to a lower energy level. This is the same principle at work in a neon lamp, the characteristic pink-orange glow of ionize
Tunnel Diodes
by
James
Tunnel diodes exploit a strange quantum phenomenon called resonant tunneling to provide interesting forward-bias characteristics. When a small forward-bias voltage is applied across a tunnel diode, it begins to conduct current. As the voltage is increased, the current increases and reaches a peak value called the peak current (IP). If the voltage i
Schottky diodes
by
James
Schottky diodes are constructed of a metal-to-N junction rather than a P-N semiconductor junction. Also known as hot-carrier diodes, Schottky diodes are characterized by fast switching times (low reverse-recovery time), low forward voltage drop (typically 0.25 to 0.4 volts for a metal-silicon junction), and low junction capacitance.
In terms of
Zener Diodes
by
James
If we connect a diode and resistor in series with a DC voltage source so that the diode is forward-biased, the voltage drop across the diode will remain fairly constant over a wide range of power supply voltages:
According to the "diode equation," the current through a forward-biased PN junction is proportional to e raised to the power of the f
Inductor Commutating Circuits
by
James
A popular use of diodes is for the mitigation of inductive "kickback:" the pulses of high voltage produced when direct current through an inductor is interrupted.
When the pushbutton switch is actuated, current goes through the inductor, producing a magnetic field around it. When the switch is de-actuated, its contacts open, interrupting current t
Rectifier Circuits
by
James
Now we come to the most popular application of the diode: rectification. Simply defined, rectification is the conversion of alternating current (AC) to direct current (DC). This almost always involves the use of some device that only allows one-way flow of electrons. As we have seen, this is exactly what a semiconductor diode does. The simplest typ
Diode Ratings
by
James
In addition to forward voltage drop (Vf) and peak inverse voltage (PIV), there are many other ratings of diodes important to circuit design and component selection. Semiconductor manufacturers provide detailed specifications on their products -- diodes included -- in publications known as datasheets. Datasheets for a wide variety of semiconductor c
How to Check a Diode from Meter
by
James
Being able to determine the polarity (cathode versus anode) and basic functionality of a diode is a very important skill for the electronics hobbyist or technician to have. Since we know that a diode is essentially nothing more than a one-way valve for electricity, it makes sense we should be able to verify its one-way nature using a DC (battery-po
A Diode
by
James
A diode is an electrical device allowing current to move through it in one direction with far greater ease than in the other. The most common type of diode in modern circuit design is the semiconductor diode, although other diode technologies exist.
When placed in a simple battery-lamp circuit, the diode will either allow or prevent current thro
Absolute dB Scales
by
James
It is also possible to use the decibel as a unit of absolute power, in addition to using it as an expression of power gain or loss. A common example of this is the use of decibels as a measurement of sound pressure intensity. In cases like these, the measurement is made in reference to some standardized power level defined as 0 dB. For measurements
Decibels
by
James
In its simplest form, an amplifier's gain is a ratio of output over input. Like all ratios, this form of gain is unitless. However, there is an actual unit intended to represent gain, and it is called the bel.
As a unit, the bel was actually devised as a convenient way to represent power loss in telephone system wiring rather than gain in ampli
Amplifier
by
James
The practical benefit of active devices is their amplifying ability. Whether the device in question be voltage-controlled or current-controlled, the amount of power required of the controlling signal is typically far less than the amount of power available in the controlled current. In other words, an active device doesn't just allow electricity to
Amplifier Gain
by
James
Because amplifiers have the ability to increase the magnitude of an input signal, it is useful to be able to rate an amplifier's amplifying ability in terms of an output/input ratio. The technical term for an amplifier's output/input magnitude ratio is gain. As a ratio of equal units (power out / power in, voltage out / voltage in, or current out /
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