LNB Skew

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Test12345

SatelliteGuys Pro
Original poster
Mar 11, 2007
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Is there a way to figure out if/how much one should skew the LNB for best results? Thanks!
 
My lnb and holder have no markings,so I twist for the highest quality reading- which usually isn't that critical.
The twisting action usually has quite a range before the quality drops.
 
Thanks all! The calculator says 12.7L. Does that mean I just turn it that many degrees to the left?
 
Here is an easy way to remember skew direction... If the satellite you're trying to hit is East of your longitude, turn the LNBF toward the East. If it's West of your location, twist it West :) ...
 
subtract your longitude from the degrees the satellite is at that your aiming for.....the remainder will be your skew angle....

if your at 79w and your aiming for 83w then your skew angle would be 4 degrees (just an example)

which way you need to rotate the lnb depends if it is east or west of your location....if it is east you will rotate counter-clockwise....if it is west you will rotate clockwise....this is looking at the LNB from BEHIND the dish....

the example above you would be rotating clockwise....
 
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The oddball nbc channels on 103w are off by 20 degrees,so you would skew for 83w then move the dish to 103w.
 
Speaking of the oddball NBC channels at 103W... is there anything good on these channels worth trying for?

My skew is set to the correct zero position for my motorized dish, but I performed a scan of 103W, and I was able to pick up a signal on the NBC channels. I think it's too weak because it's not locking on to audio or video, but it scanned in the channel info.

I'm thinking of purchasing a bracket so I can attach another LNB next to the existing one skewed just so I can receive these.
 
subtract your longitude from the degrees the satellite is at that your aiming for.....the remainder will be your skew angle....

I had never heard of that approximation before, probably because it breaks down after 30 degrees or so.
 
Speaking of the oddball NBC channels at 103W... is there anything good on these channels worth trying for?

Primetime feeds for all four time zones -- but the audio channels are set up in a non-standard manner.
 
Is there a way to figure out if/how much one should skew the LNB for best results? Thanks!

Test12345,

I would like to show you something. Take a sheet of typing paper, a CD or DVD disc, a credit card or ruler (for a straight edge) and a pencil/pen.

Lay the paper longways on your desk (landscape view). Place the disc in the center of the paper, about 1/2" from the bottom and draw a circle around it. This will be Earth (northern hemisphere on top). Mark the very top of the paper NORTH, the left side WEST and the right side EAST.

At the very TOP (north) of the circle, draw a DOT on the arc of the circle. That is your earth-based satellite installation site (your dish in your yard or on your roof).

With the ruler, draw a 1" vertical line through the DOT. Two inches above the DOT, draw another DOT and a 1" vertical line through it.
Then draw a 1" horizontal line through each DOT so that you make a Tee or a cross at both DOTs.

The cross above the "Earth" will be the satellite in orbit that is due south of your position.

Observe that both the Vertical and the Horizontal lines of both tees or crosses are in alignment with eachother. If you could bring them together by sliding them across the page, they would line up with one another. If you are aiming your dish at this satellite, you need to use 0° of skew or rotational polarization because they are perfectly lined up.

Now, draw another DOT on the circumference of the circle about 1" to the left of the first DOT. Draw two 1" lines through that new DOT. One which is tangent to the arc of the circle and one which is perpendicular to arc of the circle (and perpendicular to the tangent line).

Extend out about 2" from the circle on the line that is perpendicular to the arc of the circle and draw another DOT. Draw a 1" line through this DOT that is line with the that perpendicular line. Draw another 1" line that is perpendicular to that line at the new DOT in the sky. That forms a new tee or cross and that is the NEW satellite that you want to look at.

Do you see that this new satellite appears "tilted" to the west? Which way are you going to rotate your LNBF at your earth-based satellite dish to match the new satellite? Yep! You need to rotate the LNBF to the WEST (you need to match the satellite cross with your dish cross).

Draw it out (it's simple) and it becomes easy to imagine in your mind.

RADAR
 
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