High Definition Television

High definition television are becoming more and more popular, many people are getting a HDTV because they believe that this is turning out to be the next standard in television sets, there is no wonder to this belief since the transmission quality is definitely superior to anything that came before it. The most common thing you can hear is that someone that just got a HDTV set says that he would not have believed how fast he would get used to this phenomenal quality.

In fact, most of the HDTV users say they don't understand how they watched television "the old way", and that they can not stand to watch a regular television because of its poor quality, this is even worst for sport addicts who confess that HDTV is almost a necessity for those football games.

It is not surprising then that this is not only an American trend, this HDTV madness is on a global scale, and like any other market rules this suggests that high definition will indeed become a very accessible purchase in a few year, the demand is predicted to grow in the next few years and as more television stations start transmitting in high definition more users are expected to join the market.

The companies that make the high definition television sets say that this started as a slow and gradual excitement, much of it because many people got used to the standard television broadcast, and no one thought that there will be any advancement on the level of transmission quality, most people had thought of the DVD markets and the digital signal gadgets but not about improving the actual result that you see on screen.

The result is that slowly, but surly, many are giving the high definition television a chance and once they watch it, they are hooked, and there are high chances that they will ultimately go for the high definition.

One product that has been linked most of all to the high definition transmission quality is the plasma screen, most users say that one simply can not exists without the other, that the plasma executes what the high definition enables, and while this may be very true the costs of both are still very high and not everyone can afford to purchase a plasma television set, but experts say that like all other things, this too will change in the next few years as the standards in the television market change completely, in other words they say that most people will be surprised at how quickly they will be sitting in front of their own plasma screen at home.

Anyone looking to get a high definition television set, or a plasma screen , is strongly advised to research this market before he buys anything, this market is known for its prices fluctuations and rapid changes, so make sure you buy a good product and that you are properly covered for maintenance and guarantee. Once you decide make sure you know how to install everything properly and take good care of your electronic equipment so you can use it and enjoy it for many years.

Article by:By: Simon Oldmann

From : http://www.articlesnatch.com/ Thankyou!

Satellite broadcasting technology for TV and Radio

Television programming to the viewer's home or business. A radio signal can only travel in a straight line however. Enter the satellite. By placing an orbiting satellite at 37,000 km (22,300 miles) above the earth and having it match the earth's rotational speed (7,000 miles per hour) the satellite stays over the same spot above the earth. This is referred to as being in geosynchronous orbit.

These orbits are sometimes also referred to as Clarke orbits in honor of Arthur C. Clarke who first came up with the idea in an article he wrote back in 1945 entitled "Extraterrestrial Relays" published in Wireless World Magazine. The orbiting satellite then retransmits the radio broadcast signal back down to earth to the receiving satellite dish (mini-dish) located on your home or business. The signal then travels through coaxial cables from the dish into the receiver that is connected to your TV, where the signal is then descrambled into viewable programming for your family to enjoy.

Uplink Station

Satellite TV programming that you watches at home begins with a transmitting satellite dish or antenna located at what is known as an uplink station. The satellite dish located on your house is only 18" in diameter and is tiny compared to the huge satellite dishes used at uplink stations. These satellite dishes can be as large as 9 to 12 meters (30 to 40 feet) in diameter. The great size of these satellite dish transmitters allows for a much stronger radio signal and for better aiming of the signal at the orbiting satellite. The uplink dish is pointed toward a specific satellite and the up linked signals are transmitted within a specific radio frequency range, so as to be received by one of the transponders tuned to that frequency range aboard that satellite. The transponder 'retransmits' the signals back to Earth but at a different frequency band (to avoid interference with the uplink signal), typically in the C-band (4-8 GHz) or Ku-band (12-18 GHz) or both. The leg of the satellite signal path that transmits the signal down to the Earth station is known as the 'downlink'. Satellites can have up to 32 transponders for Ku-band and up to 24 for C-band only satellites. Typical transponders each have a bandwidth between 27 MHz and 50 MHz. Geostationary Kc-band satellites need to be spaced at least 1 degree apart to avoid signal interference. For C-band satellites the spacing needs to be at least 2 degrees.

Satellite Signal Technology

Original satellite broadcasts are converted into a high-quality, uncompressed digital stream containing a lot of data, and sends it at a speed of 270 megabits per second (Mbps) for each channel. All of this data must be compressed however or the satellite would not be able to receive the information. The system of compression used in the U.S. is the MPEG-2 compressed video format. This is similar to the system used to make DVDs. The provider could now reduce the 270-Mbps stream to about 5 or 10 Mbps, enabling them to transmit about 200 channels, instead of the 30 they could transmit before compression. These signals are scrambled so that only paid subscribers can receive them.

Mini-Dish Technology

Unlike their predecessors, today's satellite dishes are small, only 18" in diameter and are referred to as a 'mini-dish'. A typical satellite dish consists of two parts: the reflector and the feed horn. The reflector is the concave dish-shaped part of the antenna. This is the part of the antenna that captures and focuses the satellite signal onto the feed horn. The feed horn is the part of the antenna that is mounted on an arm that sticks out from the reflector dish. It takes the signal and feeds it through a cable to your satellite receiver (black box). Newer satellite dish designs feature multiple feed horns. This is so the dish can pick up signals from several satellites and clearly focus the captured signal on one of the several feed horns.

Something called a feed horn has a feature known as a low noise block down converter (LNB). This provides for clear signal. The LNB does two things: It amplifies the signal received from the satellite provider, and filters out 'signal noise,' radio signals that do not carry the satellite provider's television programming.

Satellite Receiver

The satellite receiver is simply the black box that is connected to your television set. It receives the signal from your mini-dish and then de-scrambles the signal into viewable pictures for your family to watch. The receiver does three main things: It receives and de-scrambles the signal which contains the programming. It separates the programming into the individual channels you request by way of the channel selector button on either your TV or your remote control. It tracks your Pay Per View usage, and sends your billing information for this programming to your provider.

Today, there are several different kinds of receivers: standard receivers, DVR receivers and HD receivers for receiving high definition (HDTV) television programming. DVR (Digital Video Receiver) players allow the viewer to actually Pause and Replay live TV and to record up to 70 hours on the DISH Network DVR 311 or 322 players. The DISH Network DVR receiver is an advanced dual tuner, two TV output satellite receiver and integrated digital video recorder (DVR). The DISH Network DVR's were designed so that you never have to miss another favorite TV show again. No matter what your schedule; with the Dish Network DVR you can simply record your favorite shows with just the click of a button. DISH Network offers over 500 programming channels to choose from and all DISH Network satellite programming comes in 100% all-digital video and audio.

Article By: globcos

From : http://www.articlesnatch.com/ Thankyou!

Analog vs. Digital: What in God’s Creation is Analog? And Why do We Need Digital?

The U.S. broadcast system is embarking on a transition that is the result of technological advancements. It will make better use of resources most importantly our broadband spectrum and enhance the quality of our broadcasting. Although complicated at a glance, the transition has been a progression over a number of years and will leave no one in a compromising position!
Analog televisions send signals which tell the TV’s electron gun how to portray lines on the screen. Unfortunately, this signal degrades during transmission. Analog signals are affected by changes in physical phenomena, for example, temperature, position, pressure, sound and light. This lessons the amount of fine detail in the image. Digital televisions use bit streams, lines of data consisting of ones and zeros, to send this same information. Digital signals do not degrade, therefore the picture is much better on a digital television set. They do have limitations in resolution and bandwidth similar to Analog. It is difficult to detect when degradation occurs in an analog signal but a digital systems’ degradation can not only be detected but repaired.
This knowledge enables us to immediately choose the television which will yield the better picture with all things being equal. However, the source signal also needs to be considered. As sources go, Analog is good, Analog cable is better and Digital cable/Digital satellite is best. According to an article titled TV Buying Guide by Robert Valdes, “a DVD will look better on a low-end television than an analog broadcast antenna signal will look on a high-end HDTV. That is because the quality of the digital signal sent to the analog set is far superior to the analog signal sent to the digital HDTV.”
In response to technological advances in digital programming, we are seeing a complete transition from Analog to Digital. This transition has been a long time coming! In 1996 U.S. Congress authorized an additional broadcast channel to each broadcast TV station so they could simultaneously broadcast analog and digital. U.S. Congress later announced that February 17, 2009 would be the last day for full power television stations to broadcast in analog. In 2006, all new televisions which were 25” or larger were required to be DTV ready. The requirement was then expanded in March 2007 to include all new televisions 13” or larger.
The switch to solely Digital broadcasting will free up significant portions of our valuable broadcast spectrums. This can be used for public safety communications as well as auctioned to companies who provide wireless services etc. This transition will also allow a broadcaster to offer super sharp high definition programming or multiple standard definition programs through a process referred to as multicasting. Multicasting allows a broadcaster to offer several channels of digital programming at the same time using the same amount of spectrum required for one analog program.
Analogue sets will need to employ the use of a Digital-to-Analog converter box after February 17, 2009. The National Telecommunications and Information Administration (NTIA) is offering coupons for converter boxes which are valued at 40 dollars, limited to 2 per household. The cost of the converter boxes are estimated between 40 and 70 dollars. Furthermore, Digital TV sets are backward compatible which means that existing analogue equipment such as VCRs, DVD players, camcorders and computer game consoles will work on digital TV sets.
The U.S. is embarking on a transition that is the result of technological advancements. As of February 2009, we will make better use of resources most importantly our broadband spectrum and enhance the quality of our broadcasting. The transition has been a progression over a number of years and will leave no one in a compromising position!

Article By:Allison Merlino

From : http://www.isnare.com Thankyou!