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Satellite Radio Its here! Satellite radio is a new service being offered by two companies, XM Satellite Radio and Sirius Satellite Radio. Both companies are offering over 100 channels of streaming music and entertainment. High quality sound is achieved through the use of satellites orbiting high above. Satellite radio has been commercial free and free from regulations by federal committees. The impossible, is now possible, hearing the same radio station across north America and from coast to coast. All made possible by XM satellite radio and Sirius satellite radio. Find more at: www.TopSatelliteRadio.com

XM Satellite Radio and Sirius Satellite Radio have designed satellite broadcast systems that differ but they achieve the same high quality of satellite radio. A milestone of this success is the fact that satellite radio signals that are available across the United States and into Mexico and canada. Rock and Roll No its not a genre any more! XM Satellite Radio has two satellites named Rock and Roll which remain in parallel geostationary orbit to provide radio coverage throughout the United States. Sirius Satellite Radio has chose to use three satellites in an inclined elliptical orbit. This configuration provides 16 hours per satellite of signal, which gives a great redundancy if any satellite were to fail. Playing it smart, Sirius and XM both have spare satellites, which can be called on in a moments notice if needed.

XM satellite radio and sirius satellite radio have Earth based broadcast stations that are used to send up information to the satellites, which is then dispersed through out the globe. Sirius and XM both have disk jockeys that manage, create and program music which is then sent up to the satellites. The information is then taken in by the satellites and sent through a rebroadcast of the streams to earth. The Major advantage of this is that, unlike earth-based radio stations whose signals reach listeners 150 miles away, satellite radio signals have a huge reach, and are receivable anywhere within the continental United States and hundreds of miles in each direction of the borders. Satellite Radio is growing to become a world wide network and offerings are growing throughout the world. XM satellite radio and Sirius satellite radio are making it happen!

So How Does Satellite Radio Work: First, a receiver decodes and plays the received signals through an antenna. In the beginning, some cars have used a tuner that accepts the antenna signals and then passes them to a satellite radio-ready radio for playing. Ad the concept has grown out of the car and into the home, home kits for satellite radio use direct RCA inputs for home theater and traditional stereo systems. A Growing number of choices is occurring and each company is developing a broad scope of products for consumers. Already we are seeing receivers for car-only, boom boxes, computer-only, and portables for use in car and home configurations. The companies making these products are, Audiovox, Delphi Skyfi, Terk, and plenty others are jumping on board. Both XM satellite radio and Sirius satellite radio have licensed recievers and other products for consumers use.

Scott fish is the Owner of http://www.TopSatelliteRadio.com.

Top Satellite Radio is a resource for consumers seeking the history and facts about satellite radio. We also sell electronics related to Satellite Radio. Quick Access: http://www.TopSatRadio.com

sf@topsatelliteradio.com

Is 720p vs 1080i worth being concerned about? Yes and no. If you're a consumer looking for a new TV, you can happily ignore the 720p vs 1080i debate because every TV which is described as HDTV or HDTV Ready is required to support both formats.

NOTE: You should be aware though that lots of TVs which support 1080i have fewer than 1080 lines and so scale the 1080 signal down. That's not a huge issue as even scaled down 1080i is far ahead of a regular NTSC signal. It is worth bearing in mind that more expensive HDTVs tend to have better scalers than cheaper ones, and this may be an issue.

However, for broadcasters it's a live issue. Should they broadcast 1080 lines of interlaced video or 720 lines of progressive scan? They could just broadcast two signals, one in each format, but that would use up a huge chunk of bandwidth and be hugely expensive for very little gain.

To answer the question, it's important to understand the difference between 720p vs 1080i. A 720p signal is made up of 720 horizontal lines. Each frame is displayed in its entirety on-screen for 1/30th of a second. This is know as progressive scan (hence the 'p')The quality is like watching 30 photographic images a second on TV. A 1080i signal comprises 1080 horizontal lines but all the lines are not displayed on-screen simultaneously. Instead, they are interlaced (hence the 'i'), ie every other lines is displayed for 1/60th of a second and then the alternate lines are displayed for 1/60th of a second. So, the frame rate is still 30 frames per second, but each frame is split into two fields, which your brain then puts together subconsciously.

Most of the time interlacing works fine, but for fast moving images, such as sports like baseball and hockey it can cause problems which manifest themselves as a 'stepping' effect on-screen. Progressive scan signals don't have this problem and so are better suited to sports.

ESPN puts it like this: 'Progressive scan technology produces better images for the fast moving orientation of sports television. Simply put, with 104 mph fastballs in baseball and 120 mph shots on goal in hockey, the line-by-line basis of progressive scan technology better captures the inherent fast action of sports. For ESPN, progressive scan technology makes perfect sense.'

Bottom line? For us, as consumers 720p vs 1080i is not a debate worth worrying about, so you can relax and focus on all the other criteria on your list when you buy your next HDTV.

Kenny Hemphill is the editor and publisher of The HDTV Tuner - a guide to the kit, the technology and the programming on HDTV.