Quote:
Originally Posted by elgemcdlf
If it is strictly FTA why are you looking at 110/119 and 82/91? None of which are FTA sats. In which case the lnbf required for any of those sats is not the lnbf you would use for FTA in NA.
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In earlier message, he said he was using a linear lnbf, but I guess it's possible that there is confusion.
Quote:
Originally Posted by elgemcdlf
Concerning equipment, since you state you are receiving 82/91 it was my thought that you were attempting to combine a legal subbed system with a FTA system in which case knowing what all the equipment involved is greatly helps.
If you are attempting to view G25 then either a Universal or a Standard lnbf would be fine. I have noticed differences in lnbf's and it had nothing to do with advertised noise levels. In fact I am far more satisfied with the Universal I got from Sadoun at .4 than the other Universal I have that came from a competitor with an advertised noise level of .3. I personally prefer a Universal lnbf but I do a bit of Atlantic viewing which get down lower in the freq's than birds over the US. From what I have read the lower the noise level the more sensitive the lnbf to ground noise. True or not I can not say. |
Re "gound noise", I'm not sure if you're talking about terrestrial interferrence or what, but regardless, I would think that "keeping other factors equal", having a lower noise figure should always be a good thing. However I really think that noise figures quoted by various manufacturers aren't that meaningful. I'm just guessing here, but I tend to think that some manufacturers get good noise figures by either cutting back on the gain or by quoting the best case figure across the band rather than an average or worst case figure. So I'm not surprised that the .3 isn't better than the .4 , because the .3 probably isn't truely a .3 . I am surprised though that you can actually see a difference between the .3 and the .4 , at least with respect to performance. I think over the years, I've seen noise parameters for
C-band go from over 100 deg down to around 15 deg, and have seen Ku noise figures from up around 1.3 down to their current values of less than .5 , and in all that time never really noticed much difference in actual performance, at least with the consumer equipment we use. I'm sure that those with professional equipment could see differences in noise parameters, but it's never made a difference with respect to what I could tune with the equipment I use. When you tune a sat signal, there is a certain amount of noise naturally coming in with the signal, and you need to get a reasonable signal to noise level to get good reception. The noise figure is a measure of internal noise in the amplifier, ie noise not coming from the sky, but noise that will be added to the natural sky noise making the signal to noise ratio worse, and basically putting a lower limit on the signals that you can receive. So a lower noise figure can mean that you might be able to receive weaker signals, however I've never really seen situations where going to a lower noise figure actually allowed me to tune a signal I couldn't get before.
Quote:
Originally Posted by elgemcdlf
Have no idea what Sadoun sells the little single output lnbf's for. Mine came with a dish purchase. I do have one of the Invacom QPH-031's in service and it has performed with no problems but I dislike the linear side as it is Standard and I lose out on many channels once you start looking out east. |
Yeah, the ability to get the lower band is nice, but I'd rather give that up to have compatability with analog and DCII receivers. It really makes no sense to me that the manufacturers of those universal lnbfs didn't choose different LO values. I mean, if they had chosen 9750/10750 instead of 9750/10600, then those universal lnbfs would be compatable with other receivers plus give reception of the low band. But perhaps that would be stretching the capability of the receiver when in 9750 mode, I don't know.
I have an old European lnbf somewhere, that does the low band. I'm tempted to strap that on the side of one of my current feeds to see whether it works or not. This lnbf is probably 17 years old, so it probably has a noise figure greater than 1.1. Might be an interesting experiment. The guy who gave me the lnbf said that he had used it in Europe with one of those saucer type sleds that kids use. That gives you an idea of the power of some of the European sats.