Abstract: A non-directional tap coupler for use in high power operation over a wide bandwidth is provided. The tap coupler has an input line electrically connectable to a transmission line of a distributed transmission line system, a tap line coupled to the input line and an output line coupled to the input line. The input line, tap line and output line include sections having different characteristic impedances, with all of the different characteristic impedances falling within a practical characteristic impedance range. An electrical junction where the input line electrically joins the tap line and the output line is provided with a predetermined impedance value to ensure that the sections of the tap line and the output line all fall within the practical characteristic impedance range.