The small chip with the three pins in one of your pictures, the 7805A, is a 5 volt regulator, the other one, BA10339, is a quad comparator, it samples inputs and turns on an output when there is a difference/match between inputs. That LNB looks old and built like a tank! Military maybe? Is there a number stamped into the metal behind the label, visible from the backside/inside of the cover?