A waveguide busbar for conducting microwaves includes a group input for coupling in a group microwave signal, a plurality of filter inputs for coupling in a plurality of microwave signals, a dual waveguide that comprises a first single waveguide and a second single waveguide. The plurality of filter inputs are disposed along the dual waveguide, as well as at least one adjustable coupling member that provides a connection between the first single waveguide and the second single waveguide and that is configured such that it adjusts a phase length of the connection.