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View Full Version : Circular vs. Linear: what does it mean?


pcglue
02-01-06, 12:18 PM
I have a 24" circular dish. Can I get 110, 119 and 121 with it? As I understand it, 121 is "linear", while 110 and 119 are "circular". I think this means I need linear LNB for 121, and circular LNB for 110 and 119. Is this correct? I tried, but can't find any explanation of circular vs. linear on google. Can I get all 3 of these satellites on one 24" dish? Thanks for your help.

FTA Michael
02-01-06, 02:40 PM
It's my understanding that you need a superdish to get all three positions. But since there's nothing of significance in the clear on Ku band at 121, you shouldn't need to worry about it.

Your description of the LNBFs is accurate. Most Ku-band FTA uses linear polarity; the primary Dish network satellites use circular polarity.

Ray_Clum
02-01-06, 06:58 PM
Think of it as movement of a line. Rotational moves left or right, just like running in a screw. Linear moves horizontally or vertically (like a sine curve). Just the way the waveforms work...

tdti1
02-03-06, 11:51 AM
I have a 24" circular dish. Can I get 110, 119 and 121 with it? As I understand it, 121 is "linear", while 110 and 119 are "circular". I think this means I need linear LNB for 121, and circular LNB for 110 and 119. Is this correct? I tried, but can't find any explanation of circular vs. linear on google. Can I get all 3 of these satellites on one 24" dish? Thanks for your help.

You can grab a 90cm reflector and a motor a QPH031 C/L lnbf and you will get everything :)

sat tech
02-13-06, 10:06 AM
does anyone know how to find az and ele for the 121west

FTA Michael
02-13-06, 03:17 PM
I plugged Des Moines (41.6, 93.8) into Sadoun's fine az/el calculator: http://www.sadoun.com/Sat/Installation/Satellite-Heading-Calculator.htm

Elevation 34.6
Azimuth 217.8 (actual - subtract about 2 for compass reading)
Skew 27.2