Isixhumi sohlobo lwe-F siyisixhumi se-RF esihlala isikhathi eside, esinobulili futhi sisebenza kahle kakhulu.Ivame ukusetshenziswa kumabonakude wekhebula, ithelevishini yesathelayithi, amabhokisi aphezulu kanye namamodemu ekhebula.Lesi sixhumi sasungulwa ngeminyaka yawo-1950s ngu-Eric E Winston we-Jerrold Electronics, inkampani eyayithuthukisa imishini yemakethe ye-cable TV yase-US.