Consumer Electronics Items

Introduction:

The daily use of electronic equipments are known as consumer electronics and includes TV, telephone, DVD, CD, PC, laptop etc. These equipments are manufactured throughout the world. With the advancement in electronic engineering at a continuous pace, a number of new variety electronics items flood into the market every year and the cost the existing products reduces continuously and it is one of the biggest advantage of consumer electronics industry.

Electronic waste is one of the problems associated with these electronic item and many manufacturers are now planning to deal with these waste.

Semiconductor:

All electronic devices use semiconductors and without these semiconductors none of the electronic device is complete. Semiconductor behaves like an insulator at absolute zero (-273 degree centigrade) and can be distinguished from conductor that at this temperature the outermost filled electron energy band is completely filled in a semiconductor compare to the conductor in which the band is partially filled.

At room temperature semiconductor show a very small electrical conductivity much lower than that of conductor.

Doping in semiconductor:

Most common semiconductors used for electronic devices are silicon and germanium. Although some other conductors such as iridium phosphide, gallium arsenide and mercury cadmium telluride are also used.

A pure semiconductor also known as intrinsic semiconductor, when doped with electron rich element e.g. arsenic or electron deficient element e.g. boron in very small quantity, its conductivity increases and the resultant conductor is known as extrinsic conductor. My doping arsenic (electron rich) and boron (electron deficient) in silicon, we get n-type (negative type) and p-type (positive type) semiconductor devices.

We may create a p-n junction by doping different element in different region of semiconductor and the device is known as diode. Similarly we can create p-n-p or n-p-n junctions and the device is known as triodes.

Electronic Devices

(a) Television:
It is a device by which we can receive moving pictures and sounds over a distance. The whole transmission and receiver systems require the following inputs.
1.Camera for live images or flying spot scanner for transmission of films and sound source.

2.Transmitters for transmitting both images and sounds.

3.Receiver systems for receiving these signals.

4.Display device, which is either CRT, Rear projection, LCD or plasma. To display the signal in the forms of images and sounds.

(b) Telephone:

It is the device for communicating by which two persons can send and receive sound signals over a distance. The system requires the following inputs.

1.The telephone equipment, which converts sound signals to electrical signals and electrical signals to sound signals.

2.Central exchange from where the subscribers are interconnected.

3.Wiring for connecting all the subscribers.

(c) Calculators:

It is a device used for carry out various mathematical calculations. The input required for calculator are as given below.

1.Power source (battery or solar panel).

2.Display device (LED or LCD)

3.Keypad containing all functions and numbers.

4.All electronic circuit devices.

Electronic Waste:

These are the waste electronic devices and if properly utilized may be valuable secondary raw material source for various electronic equipments and if thrown out may act as toxic due to presence of various toxic materials including lead, mercury, cadmium, arsenic etc. uncontrolled burning of these materials may also cause environmental problems.

Electronic waste is sometimes illegally sent to other countries for processing. However, due to complexity and difficulties in recycling, e-waste will remain an issue for the coming days.

Electronics Guide: How to Choose a DVD Player

Whether buying for yourself or a gift for a loved one, finding just the right DVD player isn't as easy as it seems. There are so many formats, sizes and added features for DVD players today that you might sift through hundreds of players before finding the right one at the right price. Use this quick guide to compare the types of DVD players available on the electronics market.

DVD Player Sizes

Determine what size player you will need. If you're adding a DVD player to your home entertainment system, determine where you will put it and how much space is available. Normal-sized DVD players can be rather wide so you'll want to be sure of your available space before shopping. DVD players are also very thin in height and most have a slot on the front that slides in and out for inserting the DVD. This is great if you have a wide space that is limited in height.

For odd-shaped spaces or very tight spots, there are different sizes and shapes of DVD players. These are usually available at electronics stores online so you'll have plenty of styles to choose from. The vertical DVD player, for example, sits upright similar to a vertical computer drive. It comes with a stand to hold it in a sturdy position. If you still have your old VHS collection, there are DVD/VHS combo machines that play both formats. This saves space as well. Also available are super slim DVD players and "space saver" DVD players to fit your personal needs.

Types of DVD Players

Once you determine the size you'll need, you're ready to compare name brands and features at the electronics store or website of your choice. You can often find many different brands and styles of players at one single electronics mall online. This will allow you to compare without spending hours searching through many websites.

Some of the features you'll see include progressive scan, time-slip recording, EZ editing, zoom, slow motion, HD (high definition) DVD, front audio/video input jacks, CD-R/-RW playback, MP3-CD playback, D/A converter, favorite scene selection, TV Guardian, and many others. You may not find one particular DVD player that carries every feature, so it's wise to determine which features are important to you before selecting a player. Which features will you likely use the most? Which will you probably never use?

You'll also notice there are many brand names for DVD players. Some of the well-known brands include Philips, Coby, Emerson, Toshiba, Magnavox, Sanyo, and Panasonic. Pricing for DVD players can range from around $50 to $500 depending on the features you choose.

If buying a DVD player for your child, there are also players with children's themes. The player will actually look like the child's favorite cartoon character!

To find the DVD player that's right for you, search online by brand name, features, or price to compare. Or, you can visit an online mall to compare all in one location. Besides electronics, you can also find other great items at an online mall such as computers, laptops, lingerie, pets, automotive products, telephones, jewelry, household products, toys, and more. Take your time to find the DVD player that will meet your needs. You'll enjoy years of quality entertainment!

The Inner Workings Of the Satellite Phone System

In a lot of the very remote places around the world, satellite phones are becoming more and more popular. Since these phones do not require cabling, the need for communication in these areas has been covered by the use of these satellite phones. A lot of these remote areas just do not have the infa structure available to allow for a more traditional land line phone. Radio frequencies could be considered as well but all the frequencies for radio are for the most part, already occupied with other things.

For communication, satellite phones use what is called low earth orbiting satellites or LEO for short. The main advantage to using these types of satellites over other types such as geo stationary satellites, is that there is very little latency. Since low earth orbiting satellites are quite a bit closer to the earth, there is less delay in communication.

Each satellite phone system includes a number of LEO satellites usually called a constellation. The use of many satellites makes sure that there is always a satellite visible to the phone so that calls can be made or received whenever they are needed. This ensure that there are never any missed calls or calls that get go through to the person that you are calling.

There are a number of different providers that offer these types of phone services - Iridium and Globalstar are just a couple and there are a number more. Each of these companies use various technologies to get the service done but in the end, they are mainly all the same. They all provide the satellite communication service.

A few of these companies use a multiple access method of time division to allow and increased number of calls. This includes connections that are satellite to satellite and the phones work directly with these satellites. There are also digital technologies that are used to manage the traffic of calls and sometimes this is called, code division multiple access.

When division multiple access is used, the satellites are used to forward the incoming calls directly to the telephone gateways that exist on the earth. This way, the call eventually goes through the tradtional land telephone network.

With the different ways this satellite phone technology work, the end result does not change. The basic thing is that in the end, you get through to who ever you need to talk to!