I tried to tidy up a lot in past weeks, but I'm in a bit of trouble:
I have found an old DVB-T antenna which is called 'USB antenna' and I think that means that there is a USB cable to power it (in addition to an antenna cable of course) and there is a second adapter so you can use normal power alternatively. However, I have found a second power adapter and an old USB 2 hub. - - I forgot which belongs where. One adaptor is rather small, the other one rather big; I thought the hub would need the bigger one as it sometimes has to power devices, too; but I'm not sure. I googled, but no results...