Can you tell me about LNBFs?

[TMair]

Ok I have a primestar dish, I think I need to put a new LNB on it, I have been looking at LNBFs but I realy don't know anything about them.

If I get a single feed will it do H and V, or just one?

How do I peak the polarity?

Is this one any good: KBSL1 Sadoun Bandstacked Single LNBF

Thanks for you help

 

[1ADAM12]

If you use a conical lnbf on an elliptical dish you will only get the performance of the vertical diameter. If you use the elliptical feedhorn and mount a c120 lnb to it you will get almost the performance of the horizontal axis..

If you have a 1m P* then you use a conical lnbf.

Most lnbf today are dual polarity V/H voltage switched by the receiver. One cable.

 

[Mr Tony]

Ok I have a primestar dish, I think I need to put a new LNB on it, I have been looking at LNBFs but I realy don't know anything about them.

If I get a single feed will it do H and V, or just one?

most new LNBF's will do both polarity just fine. The receiver changes the polarity. Its not like the old LNB's where there is just one "notch" in the throat and it turns 90 degrees as you flip polarity. There are 2 notches in the LNB and it automatically changes as need be

How do I peak the polarity?

you mean skew? If its a fixed dish you need to skew the LNB by twisting it. Motorized you leave it at 0. The motor will skew the LNB as it goes across the arc

 

[TMair]

Thanks for the replies!!

Ice, at first I typed skew, then I second guessed myself, and decided to go with polarity, should have trused my self I thought that is how it would work having just one feed, but thought I should ask before buying one, then being surprized...again.

1adam12, thanks I will look for an elliptical feedhorn, didn't even know about those.

Thanks again guys (I use guys as gender nutrol)
Terry

 

[1ADAM12]

Here is an example of the P*E Scalar.

 

[TMair]

Ok a couple of more questions.
I read that you need to power the H side of the primestar LNB, and that will run the V side, but if you hook straight into the V side you can/will burn out your DisEQc switch, so how would I hook it up to use the V side of the LNB?

And barring using the original LNB when would I find an elliptical feedhorn?
Thanks again
Terry

 

[1ADAM12]

Ok a couple of more questions.
I read that you need to power the H side of the primestar LNB, and that will run the V side, but if you hook straight into the V side you can/will burn out your DisEQc switch, so how would I hook it up to use the V side of the LNB?

And barring using the original LNB when would I find an elliptical feedhorn?
Thanks again
Terry

Don't know about all that. I put a 22khz switch at the lnb and the Coolsat just switched between the two.
Some times you can find the P* Horns on eBay or maybe someone here will donate one to you.
If you have the original horn then just unbolt it from the lnb and get yourself an Eagle Aspen or Invacom lnb.

 

[TMair]

Thanks 1Adam12.
I have the entire dish and lnb, it worked perfectly on G-10R, but that was Verticle I would like to get it locked on AMC 9, but those channels are H and I don't want to ruin another switch so I was thinking in the long run it would be better to just get a new LNBF and be done with it, but if there is a way to hook it up with out the problem with the switch I would be happy.
Terry

Edited to add: Is it possible to just twist the LNB around far enough that the V would become H?
TM

 

[Mr Tony]

yep. Just twist it 90 degrees and it becomes the opposite polarity

 

[TMair]

Thanks Ice, that's what I thought, I mean it makes sense but you never know.
Thanks again
Terry

 

[thebaggins]

If your Prime star LNB has separate V and H outputs you can just combine them with a 3x4 switch into one cable and then the STB can just select the input.