Dielectric plate

I picked this economical ESX 241 LNBF to replace the the previous storm damaged one on the 7.5 perfect ten dish.

I was wondering if I should insert the Dielectric plate that came with it. My arc at the moment is from 55W to 123W, not sure how many circular birds there are in this range, also does the Dielectric plate have any effect on the linear performance?

That plate is only needed for the circular satellites. If you install it, the signal would or should improve for the circular satellites, but at the same time, the signals for the linear satellites would decrease.
The circular c band satellites are below 55W, so it will not do you any good to install the dielectric plate right now. EB

Excellent, thanks EB..;)