if by "earthing" you mean taking it off the building and putting it on a pole? earthing as in to dig? does this dish move by a dish moving arm or is it stationary? a pole at least three and a half inches diameter (if the "bracket" doesn't have a coupling type mount that slides over a pole, and has a flat swivel type bracket, maybe you can weld it to the pole? might be a hard feat for a novice, and galvanized steel puts off poisonous vapor....) typical pole for mesh can be 8 feet long, buried 3 feet...this would be adequate. if you have a coupling type mount, just measure the inside diameter if you take the dish off.