The 565 Series Cross Guide Directional Couplers from MI-Wave operates from 18 GHz to 140 GHz. They are available with coupling options from 16 to 50 dB providing high isolation, low VSWR and directivity up to 15 dB. These couplers consists of two waveguides at right angles to each other, joined by small coupling slots whose size, location and orientation determine the coupling and directivity of the unit. They are unidirectional as one arm is internally terminated with a matched load. These couplers provide an efficient means for sampling power or injecting a signal into a waveguide transmission line.