The TL-FO2-HDC replaces a traditional HDMI cable with active electronics designed specifically for sending audio and video signals up to 984 feet. Simply connect the TL-FO2-HDC transmitter to your source device (often a switcher, matrix, DVD player or cable box), connect the TL-FO2-HDC receiver to your destination device (often a display or projector), connect the two units with a fiber optic patch cord (sold separately), and connect the power supplies. HDMI cables are great for transmitting audio and video signals short distances, but larger buildings and larger rooms often need electronics inline to ensure signal performance. Simply pulling a long HDMI cable or connecting multiple HDMI cables together can cause signal drop out, interference, pixelization and a host of other signal and performance problems.