Friday, 26 December 2008

DSTV Looing signal

DSTV Loosing Signal




So I have been searching all over, MultiChoice forums, Google, techies.co.za, Sats R Us etc and I acknowledge all the people who assisted and therefore linked to some of that content if I break any licensing or copyright please let me know to correct my article.




So my summarized findings:










Alignment is very important and signal strength appears to be low at my house




LNB's just don't go faulty and is most probably not aligned properly




There are a lot of people out there that call themselves professionals or “authorized” but believe me they are not.




Patience and a structured approach helps








I will spend the rest of this article on some conflicting data I have gathered please comment on my article so that we can get the "real" answers out there...




I will start from the top, the satellite and work my way down to the TV.  





The Satellite itself:
In South Africa the Eutelsat W4 satelite at 36°East is used by DSTV now what is the real sattelite called?Eutelsat W4 /SESAT 1 at 36 deg east and it can be tracked here




 The LNB:
I will say the most important peice of equipment on the complete system. The story that you need a twin LNB for Dual View is a myth! Yes you won't be able to use interactive channels on TV2 nor does it seem like you can have channels from different polirizations on the two TVs but in principle it work.There is one important stting on the LNB and that is the skew, it will determine how many degrees it must be turned for the horizontal and vertical receivers to receive signal and as sattelite signals is directional it is very important to be 100% having said that according to what it was suppose to be and how mine is set is not the same. It was suppose to be set to 15.5° skew and is currently on 30° skew [clockwise if you are infront of the dish, it will be +- 1 o clock on your watch] 




The Dish itself:
With the dish there is two parameters alignment and size - it does seem that bigger is better but as with everything there is a acceptable size and it seem to be 90cm diamater.Alignment can be along two axis:







  • horizontal [Azimuth] aka left or right



  • vertical [ Elevation] aka up or down






In SA your dish must point North-East (36°East according to my logic if you want to be directional to a statelite at that location) but I got anything from 36 to 55° on the web. There is a website I used to show me a map of the direction I must point my dish - They were spot on 100% correct for the Azimuth. The Vertical alignment was suppose to be at 58.6°and mine is at 35°- Still to confirm the axis to work from [90° - 58.6° = 31.4] So it might well be correct.  




The Decoder and Signal Strength vs Quality
It would be my happiest day if we can clear this one up, got anything from







  • If your signal strength is bellow 82% it is as good as no signal



  • To ignore signal strength look only at signal quality






Yet again I revert to logic, Strength in my mind is suppose to give you an indication of how "good" your LNB and Dish is aligned then the quality is how much interference is between the satelite and the decoder / how good will that signal you recieve be displayd or how good it will keep on going in rainy / cloudy conditions.My current signal strength / level on horizontal polirization is 60% with a signal quality of 90%. the vertical polirization is on 72% signal level with 67% signal quality and it is working very good so var.I can report that you do lose some signal level when using a splitter, pprox. 7% in my configuration.   




Well that is it for now, will do a blog with Pictures and more structure in future on this topic but just had to get it out there before the paper in my pocket get lost. 




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