UB-900i is designed to compensate signal loss on long antenna cables or passive antenna splitter. One UB-900i can compensate 10dB of cable attenuation which is about 20 meters of RG-58 cable. This product is powered by power output from antenna distributor UA-960 or from receivers’ BNC connecter. DC power supply is indicated by a red LED. Up to two UB-900i can be cascaded.