LNB Skew???

[olliec420]

thanks Tron that makes a lot of sense, i couldnt figure out why linear would need to skew but not that you say that i completely understand!

 

[qwert1515]

The reason Linear LNB's need to be skewed are because they use horizontal and vertical polarities.

The satellite broadcasts a horizontal or vertical wave to the position on ground directly below it (anywhere that has the same longitude as the satellites location).

At any other location due to the curvature of the earth and satellites orbit the wave comes at an angle, because of this angle the horizontal and vertical polarities will no longer align with a LNB in the zero position on earth if it is at a different longitude and the LNB must be compensated.

 

[olliec420]

man circular lnbs are a lot easier to deal with, but if everything was easy it wouldnt be fun right

 

[cracklincrotch]

Olliec420
Have you ever observed the "green flash" from your location? I did once when way down south on the pacific side.
Tom

Geez! I haven't heard of the "green flash" since my high school physics teach went on and on about it during one of his rants about the good ole days 15 years ago!

 

[Tron]

+'s and O's

Another way to think of skew, and why its necessary on linear and not on circular...

Picture the circular satellites sending down a signal shaped like an 'O'. No matter how the 'O' is turned, it is always the same, so skew does not matter.

Now picture the linear satellites sending a signal shaped like a '+'. The satellite closest to south from your location will look like an upright '+' (horizontal and vertical polarities). As you go east or west from your vantage point of south, the '+' will tilt (due to the curvature of the earth) toward the direction from due south that satellite is in. Toward the far east and west, the '+' will look more like an 'x' from your vantage point