7   M Hz . ▁ ▁On ▁November ▁ 1 3 , ▁ 1 9 4 7 , ▁the ▁new ▁FM ▁station ▁transition ed ▁from ▁experimental ▁to ▁commercial ▁status ; ▁increased ▁its ▁power ; ▁and ▁changed ▁its ▁call sign ▁to ▁WH K X . ▁ ▁On ▁November ▁ 1 1 , ▁ 1 9 4 8 , ▁the ▁station ▁adopted ▁the ▁call sign ▁WH K - FM . ▁ ▁In ▁ 1 9 5 8 , ▁both ▁WH K ▁and ▁WH K - FM ▁were ▁sold ▁to ▁Metropolitan ▁Broadcast ing , ▁itself ▁renamed ▁Metro Media ▁two ▁years ▁later . ▁ ▁Like ▁most ▁early ▁FM ▁stations , ▁WH K - FM ▁mostly ▁sim ul cast ▁the ▁Top ▁ 4 0 ▁programming ▁of ▁its ▁AM ▁sister ▁station . ▁ ▁In ▁ 1 9 6 6 , ▁in ▁an ▁effort ▁to ▁make ▁the ▁medium ▁more ▁commer cially ▁vi able , ▁the ▁U . S . ▁Federal ▁Communic ations ▁Commission ▁( F CC ) ▁mand ated ▁that ▁FM ▁stations ▁could ▁no ▁longer ▁duplicate ▁the ▁programming ▁of ▁their ▁AM ▁sister ▁stations . ▁ ▁See ing ▁a ▁small ▁but ▁significant ▁ground sw ell ▁of ▁support ▁for ▁the ▁medium ▁in ▁the ▁market , ▁WH K - FM ▁adopted ▁a ▁new ▁progress ive ▁rock ▁format ▁on ▁August ▁ 1 5 , ▁ 1 9 6 8 . ▁ ▁WH K - FM ▁became ▁one ▁of ▁a ▁hand ful ▁of ▁commercial ▁stations ▁in ▁the ▁country ▁to ▁try ▁that ▁format , ▁many ▁of ▁which ▁were ▁owned ▁by ▁Metro Media . ▁ ▁In ▁order