USB cable length and shirt-pocket drives?

[Walter Dnes]

  Using an approx 2 metre long USB connector cable, my card reader works
OK, but a 40 gig shirt-pocket drive flakes out, with error messages in
my logs.  Replace the cable with a 2-foot cable, and the shirt-pocket
drive works fine.  Is this an attenuation issue, or are there extra
wires in the short cable.  There is a jack for a 5 volt dc supply.
However, I'm running the drive strictly off the USB port for power.

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Walter Dnes <waltdnes-SLHPyeZ9y/tg9hUCZPvPmw at public.gmane.org> In linux /sbin/init is Job #1
My musings on technology and security at http://tech_sec.blog.ca
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