if the HR box is working then its not the lnb, first step is to check signal, hit menu, then setup, then sys setup, then go to satellite, then view signal strength, the xpndrs that lite up, are the straight 0s? or x 0 x 0 x 0 x 0 etc. as in good number, 0, good num, 0. If you have evens and odds, theres a short in the line and i would recheck your fittings. if you have all 0s then i would trace the cable right up to the lnb. make sure for no cuts or nicks etc. Corroded fittings... post back with more details and we'll try to help out more.