In order to run two separate receivers independently off of one satellite dish you will need to connect a twin LNB. An LNB (Low Noise Blocker) is the piece of the dish that sits on the end of the arm and receives information from the satellite. A twin LNB has a second coax connection so you can hook up another coax cable for a second receiver. This way you can watch one channel in one room while someone else can watch a different channel in another room..
Pull the two coax cables that run from the house to the satellite dish through the LNB arm. Feed the cables through the hollow end of the arm starting at the end closest to the dish.
Take one coax cable coming out of the LNB arm and twist the end, called an F-Connector, onto one of the coax connections on the LNB.
Connect the second coax cable coming out of the LNB arm and twist the F-Connector onto the remaining coax connection on the LNB. You should now have two coax cables fed through the LNB arm connected to the twin LNB.
Place the LNB onto the end of the LNB arm. Depending on the style of your dish there could be one or two screw holes on the arm and the LNB to hold the LNB to the dish. Slide the LNB onto the arm until the screw holes line up.
Place the screws that came with the LNB through the screw holes. Twist the supplied nuts onto the screw and tighten. This will connect the twin LNB to the dish.