Re: Battery charging problem with connected ethernet
On Thu, 4 Oct 2007 11:06:38 +0100
Stuart Prescott <email@example.com> wrote:
> I never did discover exactly what was going on here, but here are some things
> that might help you that I did find in the course of investigating this
> problem and a number of other laptop power supply-related problems we have
> been having with instrumentation in our labs.
> * the power supply in question was a non-genuine one. 
> * laptop power supplies are pretty ugly in the electronic sense. They produce
> amazing amounts of electrical noise in the 50-100kHz range that ends up
> coming out in all sorts of places where it shouldn't. Non-genuine power
> supplies are worse than genuine power supplies at this at this too. 
By 'non-genuine', do you mean 'not branded by the laptop manufacturer'
or a no-name brand? I was considering something like this Belkin unit
 for my Acer, but your warning is making me nervous!
>  it was purchased from ebay... I should have known better... non-genuine
> power supplies seem to cause many more problems than the save in cost.
>  Looking at 4 genuine power supplies and 5 non-genuine ones that we had
> available to us, we found significantly more noise coming from the
> non-genuine power supplies to the point where a couple of non-genuine power
> supplies for thinkpads just cannot be used any where near our instruments --
> don't even plug them into the same wall socket!
> Stuart Prescott www.nanoNANOnano.net
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