Isidibanisi se-N (esikwabizwa ngokuba sisidibanisi sohlobo lwe-N) sisixhobo esihlala ixesha elide, simelana nemozulu kunye nobukhulu obuphakathi be-RF esetyenziselwa ukudibanisa iintambo ze-coaxial.Yaqanjwa ngoo-1940 nguPaul Neill waseBell Labs, ngoku isetyenziswa ngokubanzi ngokusebenza okungaguqukiyo kwiinkqubo ezininzi ezisezantsi ze-microwave.