# Low noise, High Gain, 129 LNBF



## mraroid (Jun 11, 2006)

Folks....

I see third party "high end" LNBFs for sale. I see reference to "Low Noise" LNBFs. I am in the Pacific North West where the 129 satellite is marginal. I am thinking about moving a 129 LNBF to a 24" dish (or larger). While I was at it, I thought about buying a 3rd party LNBF that might have better gain, and a lower noise floor than the stock 129 LNBF that came with my D1000.

Can someone recommend a product to me?

Thanks


----------



## mraroid (Jun 11, 2006)

mraroid said:


> Folks....
> 
> I see third party "high end" LNBFs for sale. I see reference to "Low Noise" LNBFs. I am in the Pacific North West where the 129 satellite is marginal. I am thinking about moving a 129 LNBF to a 24" dish (or larger). While I was at it, I thought about buying a 3rd party LNBF that might have better gain, and a lower noise floor than the stock 129 LNBF that came with my D1000.
> 
> ...


I posted this question months ago, and no one answered. And I got the same responce a few days ago with the above post. Don't we have some tech type folks here? I will bump this post again to see if someone has a link they can post or a maybe a web site with info?

Thanks

mraroid


----------



## tnsprin (Mar 16, 2003)

mraroid said:


> I posted this question months ago, and no one answered. And I got the same responce a few days ago with the above post. Don't we have some tech type folks here? I will bump this post again to see if someone has a link they can post or a maybe a web site with info?
> 
> Thanks
> 
> mraroid


You do know that the LN in LNBF means low noise. Its pretty much required for all Satellite dishes. Those available on the retail market don't really differ that much as far as Low Noise is concerned or in performance. Some retail brands are more likely to break over time particularly in certain weather extremes, but not that different.


----------



## Oldford (Jun 23, 2006)

LNBF technology is pretty flat. They are all pretty low noise with adequate gain for the job. If it were me, to increase performance,I'd go to the largest dish that I could handle. I would guess that any dollars spent and effort expended would yield more results without regard to a dB or 2 gain in the LNB.

Good Luck, YMMV!!


----------



## gregc5985 (Jul 3, 2006)

mraroid said:


> Folks....
> 
> I see third party "high end" LNBFs for sale. I see reference to "Low Noise" LNBFs. I am in the Pacific North West where the 129 satellite is marginal. I am thinking about moving a 129 LNBF to a 24" dish (or larger). While I was at it, I thought about buying a 3rd party LNBF that might have better gain, and a lower noise floor than the stock 129 LNBF that came with my D1000.
> 
> ...


I live on the west side of Puget Sound and got an HD upgrade a couple of months ago that included a seperate Dish Network 24 inch dish for the 129 sat. I've been very happy with the results and, if you have a clean shot at the 129 sat, believe that the 24 inch dish is all you should really need.


----------



## mraroid (Jun 11, 2006)

I was looking at this LNBF:

http://www.ideamaster.com/lnb.htm

They say:

Although there are many different labels on LNB's, there are only a few companies who actually manufacturer LNB's. The LNB's we offer may have different labels, but they are checked on a spectrum analyzer. Although individual print outs are not available, typically, these LNB's show 60+ dB and 18 degrees Kelvin. This is more than twice the gain and a much lower nose temperature than many factory LNB's.

This was helpful in letting me see the relationship between temperature and a noise figure:

http://www.satsig.net/noise.htm

What I have *not* been able to find, are technical specs for the mass market LNBF that DN is selling (for the 129 satellite).

If any one knows of a link where I can read about the LNBF that DN is selling, please post it.

If you have something to add regarding 3rd party LNBFs in this application, I would enjoy reading what you have to say. My questions in this thread are of a narrow focus; I am not asking questions on how to better receive HD TV. I am not asking question about dish size. I am trying to learn about typical technical figures for LNBFs, and third party LNBFs. A lot has hanged from my C-Band experience of years ago. So, please, I know all of you are trying to be helpful, but this is LNBF question, not anything else. If you have something to add to the topic at hand, please let me know. Thanks

mraroid


----------



## robert koerner (Aug 20, 2005)

[email protected]

I'm looking for a way to reduce rain fade, and ran across your site.

Do you test the LNAs you sell with a spectrum analyzer?

If the LNAs you sell have 60+db gain @18 degrees, what are the comparable gain figures for similar Dish LNAs? 57+db @?degrees?

Is the noise figure of the LNAs below or above the internal noise level of Dish receivers?

Bob


----------



## mraroid (Jun 11, 2006)

robert koerner said:


> [email protected]
> 
> I'm looking for a way to reduce rain fade, and ran across your site.


Bob, I think a larger dish would probably go a long way in helping with that issue. Replacing the stock LNBF for a better one is costly and may not buy you much of anything.

It would be useful if you told us what part of the country you are in, and which dish you use. That way, folks will have a better idea of what to recommend. You might also tell us if you are receiving HD or not. 


robert koerner said:


> Do you test the LNAs you sell with a spectrum analyzer?


 I posted a link to a web site selling LNBFs. That site does not supply spectrum analyzer results with it's LNBFs (sound kind of fishy to me).


robert koerner said:


> If the LNAs you sell have 60+db gain @18 degrees, what are the comparable gain figures for similar Dish LNAs? 57+db @?degrees?
> Is the noise figure of the LNAs below or above the internal noise level of Dish receivers?


I do not know the answer to that question. The hope is, that someone reading this thread, will post a link to a site with specs for the LNBF that Dish Network uses.

mraroid


----------



## robert koerner (Aug 20, 2005)

I read your post, and figured I'd try and fish for some better info for you.

I'm interested in seeing what their response is.

Who knows, maybe they really do have a better LNA?

Unfortunately, I began wondering if all of rain fade is due to diminised (blocked) signal. If part of the fade is due to a change in signal polarity, extracting a few more Dbs with a "better" LNA might only slightly improve rain fade.

Don't know how it impacts sat sig from 129.

Bob


----------



## robert koerner (Aug 20, 2005)

Their response was that they haven't sold LNAs for over 10 years.

I should buy separate dishes, with separate LN(A)Bs, and appropriate switches to reduce rain fade.

All good advice to improve reception. But, no information related to selling "better" LN(A)Bs than the ones Dish has.

Bob


----------



## mraroid (Jun 11, 2006)

robert koerner said:


> But, no information related to selling "better" LN(A)Bs than the ones Dish has.
> Bob


You would think that here on this forum *someone* would know where one can find the specs for the stock LNBF that Dish network sells. Is it a secret? Maybe DN will not reveal the numbers. I don't know what the big deal is. I just want a baseline and I can't even find that......

It is frustrating.

mraroid


----------



## robert koerner (Aug 20, 2005)

I suspect, while it is an easy question to ask, an answer would be hard to use.

My guess is that part of the problem is "signal to noise" ratio coupled with Forward Error Correction, spanning a LARGE range of frequencies, both entering, and leaving the LNBs.

Bob


----------



## ericha (Jan 21, 2003)

The only way you are are going to know how good the Dish Network LNBs are is to
-Get Dish Network to tell you their purchase spec for the LNBs that they buy (very unlikely)
-Measure lots of them to find out the limits
-Measure your own

Unfortunately getting a piece of test equipment to measure the noise figure of an LNB is not going to be cheap. Actually it's going to be quite expensive. I know--my company sells equipment to do exactly this. Making precise noise figure measurements on low-noise frequency converters (the very definition of an LNB) is especially tricky.

The good news, however, is that the suggestion that a bigger antenna is probably going to help more is most likely correct. With some work, you could pretty easily double the antenna size, which gives 3 dB more signal (and about the same noise, maybe a bit less due to narrower beam width). Getting an LNB with 3 dB lower noise figure is either going to be difficult or impossible--I would guess that the noise figure of the LNBs that Dish Network sells are around 3 dB. An LNB with 1 dB noise figure is going to be expensive--probably many hundreds of dollars, if not more.


----------



## mraroid (Jun 11, 2006)

ericha said:


> The good news, however, is that the suggestion that a bigger antenna is probably going to help more is most likely correct.


Thanks for your help. I guess I have not explained my self very well. Everyone keeps telling me to buy a bigger dish. Buying and installing a bigger dish will not tell me what the noise figure (NF) is for the stock LNBF sold by DN. I am interested in learning. The goal of my questions about a LNBF is not because i want a better TV picture. I am looking for some baseline numbers.

Here is a simple explanation of some basics of LNBFs and NF:

http://www.satsig.net/lnb/explanation-description-lnb.htm

And looking at Wikipedia, I find this as typical NF figures:

Here is an example of Universal LNB:
LO: 9.75 / 10.6 GHz. 
Freq: 10.7-12.75 GHz. 
NF: 0.7 dB. 
Polarization: Linear 
North America DBS LNB

Here is an example of an LNB used for DBS:
Local oscillator: 11.25 GHz 
Frequency: 11.2-12.7 GHz 
Noise figure: 0.7 dB 
Polarization: Circular

Here is a company in the UK that sells LNBFs. I see that the noise figure is about 1/2 of what Wikipedia says is "typical".

http://www.invacom.com/products.htm

I just can't believe I am covering new ground here. Has this not been discussed before? Surely hard data is around that has NF figures for Dish Networks LNBF.... ???

Thanks

mraroid


----------



## robert koerner (Aug 20, 2005)

That is my point. The information you've found can't be used.

deciBells are based upon Logs, because of the way our ears work.

Double or half the power, and there is a 3 dB change.

What we need is signal to the sat receiver. Plus we need to know how much "noise" is in the signal. To complete the chain we need to know the Noise Figure in the receiver.

The block converter, as well as the amplifier will introduce noise into the signal. And, the receivers use error correction "software".

If I remember correctly, the ambient noise is left over from the BIG BANG. The antenna gain will always gain the ambient noise as much as the desired signal, unless there is local noise.

Easy question to formulate, but a hard one to get a usable answer to.

I still don't know what the signal strength indicator indicates, other than relative signal strength. milla volts, dBs, FEC needed?

One time I changed the LNB to a "Pro" so that I didn't have to run two feed lines into my new 522.

When I changed the LNB, the signal strength changed in my current receiver.

Bob


----------



## Richard King (Mar 25, 2002)

> When I changed the LNB, the signal strength changed in my current receiver.


Actually, the signal strength "reading" changed. We don't have enough info to know whether the base lines are changed on the "reading" when the receiver senses a different "style" lnb.

If you are looking for more signal, as stated, the LNB is not the best way to get that signal. As for rain fade, this is caused because the signal is reflected and dispursed by the rain drops so less signal reaches your dish. The best solution, as was stated, is a bigger dish.

When I started in the satellite business, about 1989 in the days of 10' dishes, a 65 degree noise figure LNB was about the BEST c-band LNB you could get. KU LNB's were MUCH worse than that at the time. At that time 18 degrees was a dream, especially in Ku band.

As for what Dish uses, I suspect that they source them from many manufacturers, including Eagle Aspen, California Amplifier, and I am sure, some unknown Chinese manufacturers. Assuming that Dish buys as most large companies do, they develop a required specification (noise figure, gain, size, etc) and send those specificatioins out for bid. I am certain that as technology advances they adjust the required specifications as need be. Low bid wins so long as they meet the specs.


----------

