▁ ▁The ▁anten na ▁was ▁mounted ▁on ▁a ▁ 2 0 0 - foot ▁tower ▁based ▁at ▁an ▁elev ation ▁of ▁ 8 0 0 ▁feet ▁in ▁height ▁above ▁average ▁terrain ▁( HA AT ). ▁ ▁Both ▁the ▁" Q " ▁and ▁" IV " ▁in ▁the ▁station ' s ▁call ▁sign ▁all ud ed ▁to ▁four - channel ▁quad raph onic ▁sound . ▁ ▁K Q IV ▁was ▁reported ▁in ▁the ▁local ▁press ▁to ▁be ▁the ▁second ▁quad raph onic ▁radio ▁station ▁in ▁the ▁world . ▁and ▁the ▁first ▁to ▁be ▁designed ▁and ▁built ▁to ▁be ▁quad raph onic , ▁But ▁those ▁reports ▁were ▁based ▁on ▁err one ous ▁information . ▁ ▁K Q IV ▁established ▁its ▁quad raph onic ▁identity ▁and ▁" R ock in ' ▁in ▁Qu ad " ▁brand ing ▁in ▁anticip ation ▁of ▁being ▁selected ▁as ▁the ▁exclusive ▁FM ▁station ▁in ▁the ▁Port land ▁radio ▁market ▁to ▁field ▁test ▁the ▁Dor ren ▁Qu ad ra plex ▁System , ▁invent ed ▁by ▁audio ▁engineer ▁Louis ▁Dor ren . ▁About ▁a ▁month ▁before ▁K Q IV ▁went ▁on ▁the ▁air , ▁the ▁F CC ▁susp ended ▁further ▁testing ▁of ▁Qu ad ra plex ▁due ▁to ▁a ▁concern ▁that ▁the ▁system ▁used ▁a ▁sub car rier ▁component ▁not ▁permitted ▁under ▁its ▁reg ulations . ▁ ▁K Q IV ▁continued ▁to ▁identify ▁itself ▁as ▁a ▁quad raph onic ▁station ▁in ▁the ▁hope ▁that ▁Qu ad ra plex ▁testing ▁eventually ▁would ▁be ▁permitted . ▁ ▁Meanwhile , ▁the ▁station ▁broadcast ▁music ▁from ▁ph