Thursday, April 1, 2010

Sunday, March 28, 2010

Powerful, but Missing Some Key Features: Nokia N900


Review:

Nokia N900: Powerful, but Missing Some Key Features

The Nokia N900 is ideal for techies who want a lot of customization and power; anyone looking for apps and aesthetics may want to go with a more mainstream smart phone.

Nokia fans disappointed by last summer's N97 smart phone get excited: The Nokia N900 ($570, unlocked; price as of December 18, 2009) delivers on its promises of fast performance and excellent Web browsing. It also offers solid multimedia features, as well as one of the best cameras I've used on a smart phone. But the N900 isn't for everyone: Some people might find the Linux-based Maemo (MAY-mo) platform confusing and not as user-friendly as other platforms. The handset is also missing some crucial features, such as app-store support and MMS messaging, as well as full Exchange support.

Read more about N900 Black Smart phone...


Tuesday, February 16, 2010

TYPES OF ELCTRONIC


Most electronic appliances, such as radio receivers, are constructed from combinations of a few types of basic circuits. Analog circuits use a continuous range of voltage as opposed to discrete levels as in digital circuits.
The number of different analog circuits so far devised is huge, especially because a 'circuit' can be defined as anything from a single component, to systems containing thousands of components.
Analog circuits are sometimes called linear circuits although many non-linear effects are used in analog circuits such as mixers, modulators, etc. Good examples of analog circuits include vacuum tube and transistor amplifiers, operational amplifiers and oscillators.
One rarely finds modern circuits that are entirely analog. These days analog circuitry may use digital or even microprocessor techniques to improve performance. This type of circuit is usually called "mixed signal" rather than analog or digital.
Sometimes it may be difficult to differentiate between analog and digital circuits as they have elements of both linear and non-linear operation. An example is the comparator which takes in a continuous range of voltage but only outputs one of two levels as in a digital circuit. Similarly, an overdriven transistor amplifier can take on the characteristics of a controlled switch having essentially two levels of output.

[A] Digital circuits

Main article: Digital electronics
Digital circuits are electric circuits based on a number of discrete voltage levels. Digital circuits are the most common physical representation of Boolean algebra and are the basis of all digital computers. To most engineers, the terms "digital circuit", "digital system" and "logic" are interchangeable in the context of digital circuits. Most digital circuits use two voltage levels labeled "Low"(0) and "High"(1). Often "Low" will be near zero volts and "High" will be at a higher level depending on the supply voltage in use. Ternary (with three states) logic has been studied, and some prototype computers made.
Computers, electronic clocks, and programmable logic controllers (used to control industrial processes) are constructed of digital circuits. Digital Signal Processors are another example.
Building-blocks:
1 Logic gates
2 Adders
3 Binary Multipliers
4 Flip-Flops
5 Counters
6 Registers
Highly integrated devices:
• Microprocessors
• Microcontrollers
• Application-specific integrated circuit (ASIC)
• Digital signal processor (DSP)
• Field-programmable gate array (FPGA)

[B] Heat dissipation and thermal management

Main article: Thermal management of electronic devices and systems
Heat generated by electronic circuitry must be dissipated to prevent immediate failure and improve long term reliability. Techniques for heat dissipation can include heat sinks and fans for air cooling, and other forms of computer cooling such as water cooling. These techniques use convection, conduction, & radiation of heat energy.

[C] Noise

Main article: Electronic noise
Noise is associated with all electronic circuits. Noise is defined[1] as unwanted disturbances superposed on a useful signal that tend to obscure its information content. Noise is not the same as signal distortion caused by a circuit. Noise may be electromagnetically or thermally generated, which can be decreased by lowering the operating temperature of the circuit. Other types of noise, such as shot noise cannot be removed as they are due to limitations in physical properties.

[D] Electronics theory

Main article: Mathematical methods in electronics
Mathematical methods are integral to the study of electronics. To become proficient in electronics it is also necessary to become proficient in the mathematics of circuit analysis.
Circuit analysis is the study of methods of solving generally linear systems for unknown variables such as the voltage at a certain node or the current through a certain branch of a network. A common analytical tool for this is the SPICE circuit simulator.
Also important to electronics is the study and understanding of electromagnetic field theory.

[E] Computer aided design (CAD)

Main article: Electronic design automation
Today's electronics engineers have the ability to design circuits using remanufactured building blocks such as power supplies, semiconductors (such as transistors), and integrated circuits. Electronic design automation software programs include schematic capture programs and printed circuit board design programs. Popular names in the EDA software world are NI Multisim, Cadence (ORCAD), Eagle PCB and Schematic, Mentor (PADS PCB and LOGIC Schematic), Altium (Protel), Lab Centre Electronics (Proteus) and many others.

[F] Construction methods

Main article: Electronic packaging
Many different methods of connecting components have been used over the years. For instance, early electronics often used point to point wiring with components attached to wooden breadboards to construct circuits. Cord wood construction and wire wraps were other methods used. Most modern day electronics now use printed circuit boards made of materials such as FR4, or the cheaper (and less hard-wearing) Synthetic Resin Bonded Paper (SRBP, also known as paxoline Paxolin (trade marks) and FR2) - characterized by its light yellow-to-brown color. Health and environmental concerns associated with electronics assembly have gained increased attention in recent years, especially for products destined to the European Union,

Friday, February 12, 2010


The invention of computer is one of the greatest advances in modern technology. It is a fairly recent invention. Computer is a substitute for the human brain. Computers are capable of doing extremely complicated work in all branches of learning. In a few
minutes a computer can perform calculations that trained mathematicians would need
years to complete. It can put thousands of unrelated facts in order. The fastest computers can handle millions of problems in a few seconds.

Television is a modern electronic device .Modern life cannot be imagined without television. TV watching is one of most favorite pastimes. Television has become the most Common and widespread source of entertainment Television is a modern electronic device .Modern life cannot be imagined without television. TV watching is one of most favorite pastimes. Television has become the most Common and widespread source of entertainment