Abstract: An amplifier for a transceiver comprising plurality of power amplifiers arranged on a base, each power amplifier comprising a power amplifier input port and a power amplifier output port; a planar power splitter arranged on the base, the power splitter comprising a power splitter input port and a plurality of power splitter output ports; each power amplifier input port being connected to a power splitter output port by a planar transmission line; each power amplifier output port being connected to a waveguide transition; a plurality of waveguides each defined by a waveguide wall, each waveguide being arranged within the base, each waveguide transition being connected to waveguide; and, a waveguide power combiner arranged within the base, each waveguide being connected to the waveguide power combiner.