I bought a reciever (2700) from my father-in-law, to hook up to a 500 dish that came with my new house. Problem is I only get less than half the channels I'm subscribed to. I have strong signal on 119, but not on all the transponders, some have zero. There is no switch detected. I'm sure the remedy is a simple one, but obviously, I have little to no idea what I'm doing here, so any advice will help.