Gid ond tranzisyon WR28-WR22 30.0-40.0 GHz 25.4mm WR4-WR5 tranzisyon waveguides 140-260 GHz 25.4mm WR28-WR22 tranzisyon waveguides 140-260 GHz 25.4mm Gid ond tranzisyon WR112-WR90 8.2-10GHz 25.4mm WRD750 trese waveguide 8-18GHz