I have WLL4070-D50 miniPCI card with atheros chipset...
Mikrotik give me only b/g modes, no a mode. how to force mikrotik to work in a mode with this card?
Thanks.

I have the same problem on this Askey card.

Hello,
can you confirm that it is really not working on 5Ghz?
Thanks.

The problem is that you probably have a "chinese fake" of the original askey card and the chinese card works with windows in a/b/g mode but with mikrotik only b/g. This can be fixed with reflash eeprom of the card with another one, for example dump from original card.