Re: usb hard drive how?

Leo Bing Whiteway (leobingw@xxxxxxxxx) writes:
I was given a 10 gig USB hard drive. It has a jack marked +/- and a cable with a
USB plug on the end made to plug into a USB socket on the computer. It also
has a USB cable.
The hard drive has:
USB 2.0 TM
I have no more info on it and can't find it with searching Google.
I am having no luck making it work or show up in lsusb.
Have any of you any ideas where I might look for info on how to hook it up and
try to use it?

That +/- jack sounds like it's for an AC adaptor to plug into. I have
very little experience with USB, and none with USB drives, but I would
think a hard drive might be pushing the limit of power available over
the USB bus. Hence perhaps it needs an AC adaptor to power it up
before it will work, rather than getting power from the USB bus?

SInce it was given to you, that's the sort of situation where an
AC adaptor gets lost along the way.

You'll have to find out, or figure out, the needed voltage and
current. Polarity is important too, but that +/- sounds like
it might define that point at least.

Look for labels that might provide the information. Look closer
just in case the jack is actually marked (I've found some of
that sort of marking can be hard to see if the color of
the plastic is wrong).

I usually find such details with web or newsgroup searches. It's
always interesting how many time someone has asked about a given
unit's power requirements in the past, or someone selling a unit
somehow includes the power requirements when advertising it.

Failing that, open up the box and see if there's a clearer indication
of the manufacturer. At the very least, one might start to make
a guess, use an ohmmeter to see which of the jack's pins goes to
ground, then follow the other line to see what it's connected to.
An electrolytic capacitor is likely connected at some point to
where the power comes in, and the voltage rating on the side
at least sets a point where the voltage will be too high.