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Rob[_40_] Rob[_40_] is offline
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Default USB Hub not working

wrote:
I have one of these USB hubs with several USB connectors, which plugs
into a single USB port on a computer. It dont work. If I plug in a flash
drive directly to the computer, I can access that drive. But if I plug
it into the hub, the drive never shows up. I tried this on 3 computers.

I opened that hub, and there is a circuit board, with each output port
connected to a trace on the board which goes to a black dot on the
board. I dont know what that "dot" is, but I assume it's a chip of some
sort, and it looks like the dot itself was some sort of epoxy placed in
the board.

This was a gift, and it's going to get returned to the store, but I am
just wondering what kind of circuit this is?

Until looking at the innards, I thought that these hubs were just a
direct connection to the input (from computer) USB. But I see there is
more to it....


There are hubs that come with a power supply so they can deliver more
power to the connected devices than can be supplied by a single port
at the computer, and there are hubs without powersupply.

It may be that yours has the powersupply misplaced and won't work
without it. Look for an extra connector on the case that is not a
USB input or output.