@GNUser: The concept of a wall-powered laptop not being able to power a radio (wifi) sounds rather odd, considering how much the average radio draws versus something like the CPU fan, which is likely to draw quite a bit more than something plugged into USB. Since you have introduced a
powered USB hub and seemingly have a working platform, you've added two new things to the mix: fresh copper pads (the USB sockets the radio plugs into) and Vcc (a secondary power supply).
The radio has four pins inside the connector, Vcc (5v "plus"), Ground, and the two pins in the middle are Data. I'm betting one or both of the outside pins are oxidized, making a poor connection with the laptop's USB pins, which are also possible to have the same symptoms.
- Power down the laptop and remove the battery (just for safety, some laptops have one or more USB ports that stay lit after the unit itself is shut off.)
- A burnishing tool is normally used, which most people don't have in their homes, but 3,000 grit or higher sandpaper is now found in most local hardware stores (Home Depot, Lowe's, etc.) which would be my second choice. Lightly sand the contacts (on the laptop) using a piece of folded high-grit sandpaper; it doesn't usually take much effort before the contacts are "shiny gold" in color. Repeat this process on any USB devices whose USB contacts are dulled; this "dull" look is actually oxidation and can prevent a solid connection between the laptop and USB devices plugged into it.
- Once "sanding" is complete, you'll want to clean out any dust/debris - Isopropyl (rubbing) alcohol on a Q-Tip (usually with some of the cotton removed so it fits nicely inside the USB connector) will help clean things up quite nicely.