I asked MT about this last year.
The issue seems to be Linux driver support so it can be integrated into RouterOS. Without drivers, lots of otherwise nice 3rd party cards can't be used.
The documents on the wavesat website refers to drivers, and Linux software, but don't make it clear what is required to make the card run.
I sincerely hope too that the MT guys are onto this. There needs to be a Wimax upgrade path, preferably with multiple band (e.g. 5.8GHz as well as licensed 3.5) support.
PCI, you would use a PCI<>miniPCI adaptor.
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