Abstract: A signal transmission and receiving system includes a controller or central processor unit and one or more peripheral units interconnected by a transmission line or bus having a plurality of conductors. Instead of providing terminator devices for the opposite ends of the bus in the controller and in the last peripheral unit connected to the bus, respectively, both terminator devices are located in the controller and the bus is looped back on itself so that both ends of the bus can be connected to a connector having two sets of contacts, one set being connected electrically to the conductors at one end of the bus and the other set of contacts being connected electrically to the conductos at the other end of the bus.