▁second - adj acent - channel ▁spacing ▁do ▁not ▁apply ▁for ▁stations ▁lic ensed ▁before ▁ 1 9 6 4 . ▁ ▁De viation ▁and ▁band pass ▁Norm ally ▁each ▁channel ▁is ▁ 2 0 0   k Hz ▁( 0 . 2   M Hz ) ▁wide , ▁and ▁can ▁pass ▁audio ▁and ▁sub car rier ▁frequencies ▁up ▁to ▁ 1 0 0   k Hz . ▁De viation ▁is ▁typically ▁limited ▁to ▁ 1 5 0   k Hz ▁total ▁( ± 7 5   k Hz ) ▁in ▁order ▁to ▁prevent ▁adjacent ▁channel ▁inter ference ▁on ▁the ▁band . ▁St ations ▁in ▁the ▁U . S . ▁may ▁go ▁up ▁to ▁ 1 0 % ▁over ▁this ▁limit ▁if ▁they ▁use ▁non - st ere o ▁sub car riers , ▁increasing ▁total ▁mod ulation ▁by ▁ 0 . 5 % ▁for ▁each ▁ 1 % ▁used ▁by ▁the ▁sub car riers . ▁ ▁O IR T ▁band plan ▁The ▁O IR T ▁FM ▁broadcast ▁band ▁covers ▁ 6 5 . 9 ▁to ▁ 7 4   M Hz . ▁It ▁was ▁used ▁in ▁the ▁Union ▁of ▁Soviet ▁Social ist ▁Republic s ▁and ▁most ▁of ▁the ▁other ▁Wars aw ▁P act ▁member ▁countries ▁of ▁the ▁International ▁Radio ▁and ▁Television ▁Organisation ▁in ▁ ▁Eastern ▁Europe ▁( O IR T ), ▁with ▁the ▁exception ▁of ▁East ▁Germany , ▁which ▁always ▁used ▁the ▁ 8 7 . 5 ▁to ▁ 1 0 0 ▁( l ater ▁ 1 0 4 ) ▁M Hz ▁broadcast