I know you asked for help few months ago but anyway. Maybe someone else is wondering too.
For enabling DWA547 wifi card you have to edit AirPortAtheros40.kext from IO80211Family.kext plugins folder. This card work on all OS X versions.
Copy IO80211Family.kext on the desktop, then "Show package content" and follow this path : IO80211Family.kext/Contents/PlugIns/AirPortAtheros40.kext/Contents/Info.plist
Replace the originals strings by this one:
I hope I did help you... even late.