HOW TO ASSEMBLE AND TRACK SATELLITE DISHES PART2

Now haven focused your dish at the satellite you wish to track, there are certain parameters that you will need to enable you scan the channels you actually want to receive on that satellite position.. Now, these Channel parameter you need for tunning your desired channels takes the form of the syntax below; channel parameter syntax: frequency, polarisation, symbol rate, FEC For example: BBC World: 12285 V 27500 3/4......, Where "BBC World" is the name of the channel, "12285" is the frequency, "V" is the polarisation, "27500" is the symbol rate(SR) and "3/4" is the forward error correction(FEC).............................................................. In my previous posts, we have talked about the frequency of transmission..... Now lets explain the rest of the parameters stated in the syntax.................... Polarisation: A transmission from a satellite can have one of four polarisations, that are dictated by the antenna(dish) used on the satellite. You must have a matching antenna(dish) to recieve them. The four polarisations are in two catagories: >>Linear polarisation: where the launcher feeds a single dipole at a time in the waveguide that can be either Horizontal (H) or Veritcal(V). Ku band transponders(Frequencier) usually (but not always) use linear polarisation, hence you will find most Ku LNBFs are linear. >>Circular polarisation: where the signal is fed to two H&V(horizontal and vertical) dipoles simulatiously in the waveguide.....Depending on the phase relationship of the feed to the two launcher dipoles determines if the polarisation is lefthand(L) or righthand(R). Typically C band transmissions use circular polarisation, when you buy a C band LNBf it will almost certainly be circular polarised. As far as your STB(decoder) is concerned it selects H&V and L&R polarisation by the same method (ie changing the DC feed voltage to the LNB), The type of polarisation is dictated by the LNBF itself. At Ku band there are advantages to using Linear polarisation,and at C band Linear polarisation tends to be distorted (rotated) as it comes through the atmosphere, hence circular is used as it is not affected in the same manner. In the US the two large DTH pay TV operators (DirectTVandEchostar) both use circular polarisation in Ku band rather than linear, thus,the Skew (polarisation alignement) need not be adjusted, therefore one less thing for home installers to worry about. .............................................. symbol rate parameter: Effectively, this is a measure of how 'fast' data or signal is sent from the satellite to your Decoder and its measured in megabaud,so you may call it the baud rate of satellite transmission................... Forward error correction(FEC): It corrects any kind of error in the satellite signals before its transmitted hence the name "forward error correction". .............................................. Now lets talk about how you can track your satellite dishes ..............................................NOTE: You need to know the tunning parameters of the channels that you wish to receive and the satellite position on which they are located. Again note that every satellite position has what is called a "FOOTPRINT" wow what the heck is this again!!! Well relax, footprint is simply the range of areas that the signal beams of any satellite position covers. This means that you can only receive the channels on a particular satellite position if the footprint extends or covers up to your location..... Now you may probably be wondering how you can know if the footprint of a particular satellite covers your area.... How do i get these informations and the channel parameters?,well don't worry its quite simple..... Just go to the following websites to acquire all the informations you need regarding any satellite position and channel: .............................................. http://www.lyngsat.com Lyngsat is very popular and highly reputable,they are 99.5% accurate and i always use it,thus i recommend it..... However you may also use; .............................................. http://www.kingofsat.net http://www.flysat.com .............................................. Now if you know the name of the channel you want,go to search engines like http://google.com and type in the channel name lyngsat or kingofsat or flysat for example: "BBC ONE lyngsat" or "BBC ONE flysat" or "BBC ONE kingofsat" .............................................. However to save you from all these stress,manufacturers of satellite decoders often equip their products with various satellite positions and their associated channel parameters,thus saving you all the stress. They keep you updated with the latest satellite positions and their associated channel parameters whenever you update your decoder with their latest version of software(firmware) available for your brand.................................. Now haven known all these,you may proceed as follows in the next part3 of this topic..stay tuned