What do you mean that the vertical polarity only uses 18"? The total reflector area determines the gain for either horizontal or vertical polarity.
The vertical only uses from bottom to center to top. In a line. 18 inches this is the only part it uses.
Horizontal runs left to center to right. The wide part of the satellite. 36 inches
The satellite is skewed and the lnb only looks vertical. Which is inline with the 18inch part of the satellite. I'm not sure why they used the satellite they did.
Unless in the future they plan to add more satellites. Which is easier vertical. Since the dish is so wide.
They would just upgrade the lnb.
But then again. Everyone is using wide satellites so it may have been a cost issue. Cheaper
But I only know I picked it up with a rca 18inch satellite because I was trying to do my own installation. And I thought my Universal lnb would work. But as I found out.
It will not. You have to get an lnb 10750
My Universal one would not work because the box does not let you choose the lnb. And like a fta receiver. If you change the setting to 10700. The frequencies will be off. So 11840 would be something like 11830. And this box will not show any readings unless it matches.
I have thought about hooking it back up to my system and hooking a fta on the same line. And setting it to 10750. To see if it would work.
I'll keep you posted. If the signal is better and does not go out during storms. I'll put it on my other c band satellite. But I will test it on a bigger round ku satellite. To see how dependable it is. It would be going from 18 inches to over 30. That should be a good gain.