I have an H23 Receiver and took it down to florida where there was Direct TV in the house we rented.They had a new package which was basic and mine has Football and Hockey package.I disconnected theirs and hooked up mine.Trouble was when I returned I get this 775 message that it needs a Power Inserter.Does it matter if we get a P21,P28 or P29.Our dish is a Slimline.