On 12/15/05, Mike Hord <mike.hord@gmail.com> wrote:
> Medium-to-long explanation follows this executive summary:
>
> Has anyone noticed any noise issues related to Dell laptop
> power supplies?
>
> Full story:
>
> I'm working with meidum precision analog signals-
> 16 bit (hopefully).  We were noticing intermittent noise in
> the output, which was usually present.  The acquistion
> system is connected to the computer via vanilla serial
> (no USB adapter, just a port on the laptop).  Finally, the
> noise can be eliminated by unplugging the supply from
> the laptop.  Unplugging the supply from the wall doesn't
> help, only unplugging the supply from the laptop.
>

Sounds like a ground loop, except for the "Unplugging the supply from
the wall doesn't help" part.  Are you physically pulling the plug from
the wall or just shutting off a power strip?

Regards,
Mark
markrages@gmail
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