What is noise ratio of LNB's

[billinmidmich]

Hi, I was wondering if anyone knows what the noise ratio is for the PROPLUS LNB's? Is it worth the expense to purchase any of the 0.3 LNB's? I am going to install a 31" dish as it is.......so would I gain much to go to the 0.3?

 

[Smith P.]

You should distinguish Low noise parameter from Gain parameter; if you live in noise environment or targeting two close satellites, then SNR is your priority; all other cases, like using bigger pan and high gain LNBF will not force you search for low noise figure LNBF.

 

[RonD]

Noise figures can be misleading, and don't have much to do with the satellite signal itself, they are numbers related to the amplifier in the LNB.
All amplifiers inject noise during amplification, audio, video or LNB amplifiers.
For Ku LNBs the lower the number the less noise it would inject, but they also tend to not give you as much gain, so your actual signal level may go down but you are getting a cleaner signal.

Dish size, period, is the best improvement you can make for better signal levels.
If you are at the edge of a satellites footprint or it is low on your horizon so you are going through a lot of atmosphere and are also get earth radiated ku freqencies then a lower db LNB may get you a watchable picture over a factory DN LNB.
Most who spend the money on a lower db LNB do not notice a difference, and the money would have been better spent on a larger dish.

And to answer the original question a DP or DPP LNB should be about .6db

 

[billinmidmich]

Noise figure can be misleading, and don't have much to do with the satellite signal itself, they are numbers related to the amplifier in the LNB.
All amplifiers inject noise duing amplification, audio, video or LNB amplifiers.
For Ku LNBs the lower the number the less noise it would inject, but they also tend to not give you as much gain, so your actual signal level may go down but you are getting a cleaner signal.

Dish size, period, is the best improvement you can make for better signal levels.
If you are at the edge of a satellites footprint or it is low on your horizon so you are going through a lot of atmosphere and are also get earth radiated ku freqencies then a lower db LNB may get you a watchable picture over a factory DN LNB.
Most who spend the money on a lower db LNB do not notice a difference, and the money would have been better spent on a larger dish.

Thanks for this reply. It's along the lines of what I was thinking. I have had a Cband system since 84 and had to learn a lot about focus, dish alignment and so forth. The person I purchased my system from was what I would call a Mail Order Dealer....he didn't really know what he was doing. I enjoyed my Cband dish with all the wild feeds and virgin feeds of services. I have had a projection TV since then also. I have always had a superior picture. I never lost my signal....unless it was Solar Outage. That's why I am putting in 2 31" dishes for my Dishnet. Right now with their cable on a stick dish....rain or heavy cloud cover and the signal is gone. I have it aimed probably as good as it can be....my signals are 103 to 107(except for 129 sat, that's why I look at 61.5 with second dish). I'm in midmichigan and surrounded by the Great Lakes. So rain or cloud cover is sometimes often, not to forget the snow in winter also.

 

[aegrotatio]

Thanks for this reply. It's along the lines of what I was thinking. I have had a Cband system since 84 and had to learn a lot about focus, dish alignment and so forth. The person I purchased my system from was what I would call a Mail Order Dealer....he didn't really know what he was doing. I enjoyed my Cband dish with all the wild feeds and virgin feeds of services. I have had a projection TV since then also. I have always had a superior picture. I never lost my signal....unless it was Solar Outage. That's why I am putting in 2 31" dishes for my Dishnet. Right now with their cable on a stick dish....rain or heavy cloud cover and the signal is gone. I have it aimed probably as good as it can be....my signals are 103 to 107(except for 129 sat, that's why I look at 61.5 with second dish). I'm in midmichigan and surrounded by the Great Lakes. So rain or cloud cover is sometimes often, not to forget the snow in winter also.

I was going to do this but with a larger dish it is more difficult to peak for the orbital locations that have two or more satellites co-located. In those cases the satellites are 0.2 degrees apart (or thereabouts). The result is that you'll get great SQ on some transponders but not others--even on spotbeams that you got high SQ on the smaller dish. At 110 there is Echostar X and Echostar 8. At 119 there will be no problem for now, as there is only one bird there for each service (for Echostar and DirecTV). For DirecTV there are three(!) birds at 101, each spaced slightly apart. For Bell ExpressVu there are two birds at 82. At 148 there is Echostar 1 and 2. Finally at 61.5 there are Echostar 3 and 12 (nee Rainbow 1).

Let us know how it works!