Phil, Just last week I "dumped" all my archives from Duane, W8BDF (sk), I suppose his frog is long gone too, hi. On QF-1, I have -3- QF-1As here in shop. They all have dual audio taper 500K pots. ALSO, they are split knurled shafts. Have set screw knobs on them. These are all PC mounted. Dunno if the 1A is different or not. 73 Rod K0EQH