That card will not work as an AP on 5GHz.
from Arne.F
Not really it is a Intel/US government decision to not let the user configure the country code of the hardware. A card that has programmed country code “00” will not work with linux in 5Ghz AP mode and the firmware not allow to set the region. You need a correct programmed card for you county.Intel cards only works in client mode at 5Ghz if they are set to “00”
that is the reason why we not suggest to by Intel wlan cards.
I ran into the same issue with one I had laying around, I instead got two ceiling mounted AP’s.