Filter lnb used to reject wimax interference which is used by wireless mobile broadband which operates in arround 3600Mhz it disturb C Band signal,here in Bangldesh there are two operator which use this spectrum. I already posted a video regarding my signal in these blog signal was not stable with normal lnb like 3.4-4.2 with a noise figure of 17k i even get a single signal 15K works but its not stable this solid lnb works fine under this interference.