RE: [OT] USB, electronics and ground

["Paul Gale" <groups@xxxxxxxxxxxxxxxx>]

Hi Wayne,

Not sure - this PC is a real mess at the moment - refusing to boot most of
the time, CMOS settings getting screwed etc - when it does boot, it crashes
every now and then. My theory at the moment is that the mainboard is
screwed and maybe was caused by dodgy USB power etc?

I got a shock (light tingling) from a USB cable shield yesterday -
connected to a newish Belkin hub but when I touched it today, it's fine.
Maybe I inadvertently was touching the PC case at the time? Kind of shock
you get when sometimes touching audio leads whilst holding other equipment.

Anyone else know what kind of voltage you should expect between grounds
like this?

Can I earth the case and any other kit maybe?

What steps should I take to test all the earths - will testing voltages
with a meter help?

Paul.


> -----Original Message-----
> From: ukha_d@xxxxxxx [mailto:ukha_d@xxxxxxx] On Behalf Of
> Wayne
> Sent: 07 September 2006 23:24
> To: ukha_d@xxxxxxx
> Subject: Re: [ukha_d] [OT] USB, electronics and ground
>
> Hiya,
> One thing that springs to mind when I was reading this, back in the
old
> days when pc cases had little mini speakers that you connected to the
> mother board (rather than the little on board beeper things you get
> these days), we ran into a problem whereby if the speaker connection
> ever got connected to the frame of the speaker (and so to the outside
of
> the case) - that gave the cable a real problem - in some instances
> melting the plastic outer.
>
> You haven't got any grounding going on with internal stuff in the pc?
>
> Cheery
> Wayne.
>
>
> Paul Gale wrote:
> > I seem to have a problem with ground or earthing here. When I
plug in
> USB devices to my main PC, I get small sparks between the shield and
the
> PC case. This sometimes causes the PC to hang (not surprisingly!). I
guess
> I have different
>
>
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
>