A T-junction microwave applicator and a method for making a T-junction mi crowave applicator with a microwave source supplying electromagnetic energy through a junction arm to a pair of collinear arms extending in opposite dir ections from their junction with the junction arm. The two collinear arms fo rm a main waveguide terminated in end walls in which entrance and exit ports are formed for a conveyor to convey material to be heated through the main waveguide for exposure to electromagnetic energy. A rectangular conductive r idge in the wall of the main waveguide opposite the junction arm extends the length of the applicator. A cylindrical tuning bar spanning the junction is positioned vertically in a plane perpendicular to the axis of the main wave guide to maximize power transfer to the material to be heated.
