The computer in question is a HP desktop model, that came without any wifi adapter and has no on/off switch for radio. I think I am experiencing the same problem as Doug, i.e. The "cable" is disconnected. I am inclined to belief it means that the radio is not turned on. Upon research it turned out other people have experienced the same problem, using different operating systems. As a workaround the following video mentions to cover pin 20 with insulation tape:
https://www.youtube.com/watch?v=yzAKcmlaH1M . I am a bit hesitant to perform this modification, because it was a PITA to put the card in the computer in the first place, especially attaching the antenna's without proper tooling is troublesome. Furthermore linux is able to turn the radio on, so there should be a way of achieving the desired result using just software. Unfortunately I have no idea how the driver implements the activation of radio, what the deficiencies of the current driver are and how to fix them (especially without source code).