The ARRIS 1GHz Accessory SP100, DC100/8, DC100/10, DC100/12 Starline 1 GHz Splitter and Directional Couplers STARLINE® Series are ARRIS’s STARLINE 1 GHz splitters and directional couplers that are used with the 1 GHz Mini Bridger series amplifiers, model MB100. The purpose of these devices is to activate and direct signal to output ports 3 and 4 in the MB100 amplifier. The MB100 amplifier is shipped with a jumper installed that can be used to activate either port 3 or 4 as the second output port.