Types of Satellite TV Systems - TVRO and DBSWritten by Gary Davis
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TVRO systems are often referred to as Big Dish TV, C-Band Satellite TV and BUD (Big Ugly Dish). DBS - Direct Broadcast Satellite Satellite TV via DBS is done in Ku-Band. These satellites work on higher frequencies and can transmit higher power signals. This means that much smaller dishes can be used to receive signal. A small dish of 18 inches is already enough to receive all satellite TV by Satellite TV. This makes it possible to have satellite TV from an apartment on 10th floor, if you have a clear line of sight to south. DBS is for everyone. The satellite dish is so small that it is not an obstacle like with for instance TVRO dishes of 3 to 6 feet. Once installed dish needs no maintenance since it is aimed at just one satellite. Some dishes actually have 2 or more feeds which makes it possible to receive signals from more than 1 satellite. There are no free channels available on DBS satellites as these are often owned and used by satellite TV provider it self, while TVRO satellites often are used by those who rent space on satellite for a limited time. TVRO systems are meant for, for instance, transport of unedited materials between continents, but also within one continent. DBS is meant for everyone with a simple, low cost installation of system. Often installation is for free as it really is very easy to do. The only thing that is needed is a bit of knowledge of where to find satellite and tools that make this even easier. A qualified installer will find satellite and point it to maximum reception within minutes.
Gary Davis is owner of Dish Network Satellite TV, has several years experience in the Satellite TV Industry and has written several articles on satellite TV.
| | How a Satellite TV Antenna WorksWritten by Gary Davis
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A satellite TV Antenna or parabolic antenna works on same principle. The frequencies used by satellite transmissions are of much higher frequencies; 2 Giga Hertz or higher. Wavelengths get so short at these frequencies that it is not possible anymore to transmit using a pole antenna and transmit in all directions. The power needed would be very high because high frequencies are subject to much more resistance from atmosphere. Bundling all transmitted power into a beam improves power transmitted in one direction by a huge factor. Depending on distance between transmitter and receiver amplification compared to a normal pole antenna can be as high as 40 to 50 dB (which is as much as 10.000 to 100.000 times amplification). In reality beam is not completely straight, but gets wider over distance. The angle is small, but in case of an antenna on a satellite that transmits all over USA angle is actually a little bigger so that whole USA is covered. The antenna at your roof or in your garden is pointed at satellite and receives signal and does same thing; it bundles radio waves into a point, thus amplifying radio signal with 40 to 50 dB. (see illustration below). 
Amplification in whole path is extremely big. The transmitting antenna amplifies, receiving antenna amplifies, transmitter it self amplifies, and receiver itself also amplifies signal. A total amplification of over 120 dB (over 1.000.000.000.000 times) is necessary because atmosphere and also long distance just decrease signal power a lot.
Gary Davis is owner of Dish Network Satellite TV, has several years experience in the Satellite TV Industry and has written several articles on satellite TV.
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