In article 4a4aec56.1163774312@localhost, Don Pearce
wrote:
On Fri, 26 Jun 2009 16:41:19 +0100, Chris Isbell
wrote:

On Fri, 26 Jun 2009 12:23:17 GMT, (Don Pearce) wrote:

Well, my amplifier certainly ash an earth connection (and so does my
PC, hence the isolating line transformer for the sound card). But all
the auxiliary stuff has mains plugs with a plastic earth pin. They
have kite marks, so I presume they are legal.

Could you possibly provide details of the isolating line transformer,
please? (My work laptop is eathed and causes some 'interesting' noises
when mains powered.)

Thanks,

Yup - I bought it in Maplin. It is a Shark, model VW43W ground loop
isolator.

This makes me wonder as I've not checked. I have assumed USB carries ground
between units, so could produce a loop if both are earthed. Is this
correct?

Slainte,

Jim

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