BLACKBERRY

Airtel's Blackberry was an answer to the Nokia 9500 Communicator, Nokia 9300 Smart phone and Sony Ericsson's P910i. Blackberry also pioneered 'push mail' and owns 77% of the global market. Currently, to own a Blackberry the cost alone is around 18-20 thousand but it is worth the price as it offers value for money. With Hutch also entering this market segment the competition has gotten fiercer.

The Blackberry can easily split the world into two - those who own one and those who cannot. The first thing one would notice when comparing a mobile to a Blackberry is its shape and size, while a mobile is mostly skinny, the Blackberry is wide and short in stature. It is slightly difficult to get accustomed to, but one gets used to it within a week that you just can’t part with it.

It has speakerphone as an option, great sound clarity, great display and a well defined keypad. All in all, the Blackberry doesn't have to be made known as it is already very popular. If you want the best in email services then a Blackberry is the handset for you.

Light pen and Space mouse

A Light Pen is a pointing device shaped like a pen and is connected to a VDU. The tip of the light pen contains a light-sensitive element which, when placed against the screen, detects the light from the screen enabling the computer to identify the location of the pen on the screen.

Light pens have the advantage of 'drawing' directly onto the screen, but this can become uncomfortable, and they are not as accurate as digitising tablets.

The Space mouse is different from a normal mouse as it has an X axis, a Y axis and a Z axis. It can be used for developing and moving around 3-D environments.

Nokia N93

General
Network
UMTS / GSM 900 / GSM 1800 / GSM 1900
Announced
2006, April
Status
Available
Size
Dimensions
118 x 55.5 x 28.2 mm, 133 cc
Weight
180 g
Display
Type
TFT, 256K colors
Size
240 x 320 pixels, 36 x 48 mm

- Second 65K colors display (128 x 36 pixels)- Twist and rotating screen- Downloadable themes
Ringtones
Type
Polyphonic (64 channels), MP3
Customization
Download
Vibration
Yes
Memory
Phonebook
Yes
Call records
Yes
Card slot
miniSD, hot swap, 128 MB card included, buy memory

- 50 MB shared memory
Data
GPRS
Class 32, 107.2/64.2 kbps
HSCSD
Yes (via PC dial-up)
EDGE
Class 32, 296 kbps; DTM Class 11, 236.8 kbps
3G
Yes, 384 kbps
WLAN
Wi-Fi 802.11b/g
Bluetooth
Yes, v2.0
Infrared port
Yes
USB
Yes, v2.0
Features
OS
Symbian OS 9.1, S60 3rd edition
Messaging
SMS, MMS, Email, Instant Messaging
Browser
WAP 2.0/xHTML, HTML
Games
Yes + Java downloadable, order now
Colors
Black, Silver
Camera
3.15 MP, 2048x1536 pixels, 3x optical zoom, Carl Zeiss optics, autofocus, video(VGA 30 fps), flash; secondary CIF video call camera

- Video calling and download- UPnP technology- Java MIDP 2.0- Push to talk- MP3/AAC/MPEG4 player- T9- Stereo FM radio- TV out support- Voice command/memo- PIM including calendar, to-do list and printing- Photo/video editor- Integrated handsfree
Battery

Standard battery, Li-Po 1100 mAh (BP-6M)
Stand-by
Up to 240 h
Talk time
Up to 5 h

ROBOTS

ROBOTS

Robot, self-governing, programmable electromechanical device used in industry and in scientific research to perform a task or a limited repertoire of tasks. Robots are a subcategory of automated devices. Although no generally recognized criteria exists that distinguishes them from other automated systems, robots tend to be more versatile and adaptable (or reprogrammable) than less sophisticated devices. They offer the advantages of being able to perform more quickly, cheaply, and accurately than humans in conducting set routines. They are capable of operating in locations or under conditions hazardous to human health, ranging from areas of the factory floor to the ocean depths and outer space.

The term robot itself is derived from the Czech word robota, meaning “compulsory labour”. It was first used in the 1921 play R.U.R. (which stands for “Rossum's Universal Robots”) by the Czech novelist and playwright Karel Čapek, to describe a mechanical device that looks like a human but, lacking human sensibility, can perform only automatic, mechanical operations. In the play, however, the robots proved much more capable than that, eventually conquering and destroying their makers—a recurrent theme in science fiction since that time. The term androids is now generally reserved for human-like figures of this sort, ranging from electromechanical robots in human form to human-like creatures made entirely of biological materials.


Computers today are equipped with a small microprocessor or microprocessors that can handle the data being fed to them by various sensors of the surrounding environment. Making use of the principle of feedback (see Cybernetics), robots can then change their operations to some degree in response to changes in that environment. The commercial use of robots is spreading, with the increasing automation of factories, and they have long since become essential to many laboratory procedures. Japan is in the forefront of nations exploring robot technology. Whether the androids of science fiction will ever become a reality is not yet possible to predict, because duplication of even such seemingly simple acts as bipedal walking has proved enormously difficult. The question of “intelligent” androids must similarly be left to the future of artificial intelligence as a whole. In the meantime, however, robots should continue to expand their applications; the home-made-robot kits available today may be one sign of the future.

EARTH'S MAGNETIC FIELD

EARTH'S MAGNETIC FIELD

· A powerful magnetic field surrounds the earth, as if the planet had an enormous bar magnet embedded in its interior.

· However, geophysicists believe that convection currents of charged, molten metal circulating in the earth’s core are the source of the magnetic field.

· A compass needle is a true bar magnet; one end of it is called “north-seeking” because it is attracted to the magnetic pole that lies within the earth in the northern hemisphere. The other end of the compass needle is a magnetic pole of the opposite kind, and is therefore attracted to the earth’s other magnetic pole. Since opposite types of magnetic pole attract each other, the pole in the northern hemisphere, although called the north magnetic pole, is itself of the south-seeking type, and vice versa for the opposite hemisphere.

RADIO

hi guys,my this posting is on a device which is very often used by all of us....radio।

INTRODUCTION:
The principle of radio is electromagnetic waves। Radio, system of communication employing electromagnetic waves propagated through space। Because of their varying characteristics, radio waves of different lengths are employed for different purposes and are usually identified by their frequency।
The shortest waves have the highest frequency, or number of cycles per second; the longest waves have the lowest frequency, or fewest cycles per second। In honor of the German radio pioneer Heinrich Hertz, his name has been given to the cycle per second (hertz, Hz); 1 kilohertz (kHz) is 1000 cycles per sec, 1 megahertz (MHz) is 1 million cycles per sec, and 1 gigahertz (GHz) is 1 billion cycles per sec। Radio waves range from a few kilohertz to several gigahertz। Waves of visible light are much shorter। In a vacuum, all electromagnetic waves travel at a uniform speed of about 300,000 km per second।


PARTS OF RADIO:

A)TRANSMITTER

i)oscillators
ii)modulations
iii)antenas
Essential components of a radio transmitter include an oscillation generator for converting commercial electric power into oscillations of a predetermined radio frequency; amplifiers for increasing the intensity of these oscillations while retaining the desired frequency; and a transducer for converting the information to be transmitted into a varying electrical voltage proportional to each successive instantaneous intensity. For sound transmission a microphone is the transducer; for picture transmission the transducer is a photoelectric device.


B)RECEIVERS

i)amplifiers
ii)high fidelity systems
iii)distoration
iv)noise
v)power supply

The essential components of a radio receiver are an antenna for receiving the electromagnetic waves and converting them into electrical oscillations; amplifiers for increasing the intensity of these oscillations; detection equipment for demodulating; a speaker for converting the impulses into sound waves audible by the human ear. In most radio receivers, oscillators to generate radio-frequency waves that can be “mixed” with the incoming waves.

CELLULAR RADIO TALEPHONE

CELLULAR RADIO TELEPHONE

INTRODUCTION:
Cellular radio telephone, also called as cellular telephone or cell phone consists of a low-powered, lightweight radio transceiver (combination transmitter receiver), which provides voice telephone service to mobile users. Cellular telephones operate as portable telephones; whereas normal telephones require a cord that connects to a jack in order to access the extensive wire line networks operated by local telephone companies, cellular telephones are not restricted by a cord. Cellular telephones have become very popular with professionals and consumers as a way to communicate while away from their regular phones, while traveling or when in remote locations lacking regular phone service.


HOW DOES IT WORK?????
Cellular telephones work by transmitting radio waves to cellular towers. These towers vary in the area they cover and can receive nearby cellular telephone signals from distances as short as 1.5 to 2.4 km to distances as long as 48 to 56 km. The area a tower can cover is referred to as a cell; the towers within these cells are networked to a central switching station, usually by wire, fiber-optic cable, or microwave. The central switching station handling cellular calls in a given area is directly connected to the rest of the wired telephone system. Cellular calls are picked up by the towers and relayed to the rest of the telephone network. Since the cells overlap, as a mobile caller moves from one cell into another, the towers “hand off” the call so communication is uninterrupted.

HISTORY:
The first commercial cellular telephones were tested in the late 1970s by Illinois Bell in Chicago, and they were a great success. Cellular service carriers began nationwide operations in the mid 1980’s. The radio signals often interfered with those of other commercial radios, and due to the technology of the day the frequencies could not be reused as they can today. Therefore, limited numbers of channels were available for callers, and the service was unreliable and costly. Because of the consumer demand for cellular telecommunications, the Federal Communications Commission (FCC) in the mid-1990s authorized up to six additional mobile telephone service providers in each service area.