In a single receiver residential installation there is a single cable from receiver to LNB and the receiver uses different power supply voltages (13/18V) to select polarization and pilot tones (22 kHz) to instruct the LNB to select one of the two frequency bands.
In a single receiver residential installation there is a single coaxial cable running from the receiver set-top box in the building to the LNB on the dish. The receiver uses different power supply voltages (13/18V) to select antenna polarization, and pilot tones (22 kHz) to instruct the LNB to select one of the two frequency bands.