Where do I place my LNA?

Sandbox

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Hey All,

Just purchased a 17dB Fracarro in-line Low Noise Amplifier. Where do I install this on my home setup? Does it go directly after the LNB? or immediately before my receiver?

I'm guessing the latter is wrong as you'd be amplifying the noise picked up throughout the length of your RG6.

Any info would be much appreciated.

Sandbox :)
 
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I would put it as near the LNB as possible, depending on how to protect it from weather conditions.
What does the installation user guide says?
Suggest to contact the manufacturer and ask him how to install it, if you are not sure or don't want to take the risk.
Is it really manufactured by Fracarro or they they just supply it?
What does the logo, if any, tells you?
 
rolfw

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How long is the cable run?

Many advise that the amplifier should be half way along the cable run, if not, then near the LNB, but if your cable run is less than 40m, you will probably derive no benefit whatsoever.
 
Sandbox

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Thanks for the replies.

It came with no installation notes - except for the logo on the thing that has a pic of a receiver on one end, and a sat dish on the other.

I wanted to see if it would boost my satellite reception of W3A @ 7'E which I've pulled in from Bahrain. My cable run is VERY short... no more than 15 feet.. dish is just on the other side of my wall.

But... after installing it i've noticed a 2% increase in signal 'quality' which now reads 64% but Signal level which used to hover at around 65% mark has shot upto 93% .. BER is 0

Don't know if I've done more harm than good :eek:
 
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The reason you have a higher signal level is because the amplifier has a gain in dB and this will increase the incoming signal (dBuV).
However, you have most likely introduced more noise within the carrier and now have a poor CNR.

Line amplifiers will not help on a short runs as explained.

Having a gain of some 17dB on such as short cable run, caution has to be taken not to over drive the receiver with signals out of it's operating window.

The only way to increase signal on a short run is to use a larger dish for a better CNR OR an LNb with a lower noise figure.
 
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