hi i'm new to directv, formerly a dish customer, i had dtv installed at my house and got an extra d12-100 receiver and used 18x20 dish with 3lnb. but when i installed them at my shop i've got no signal at all, thought the dish was blocked so i moved it up the hill it has a very clear shot to the south and still nothing so i thought the distance was too far, but when i took the receiver to the dish, still nothing, is the dish bad? the receiver works fine at home with my slimeline 5 dish, but when i changed it to the other dish type i got nothing, please help.