Peter van Hoof wrote:
> My guess would be you have a groundloop.
> If you can run either the computer or the powersupply of the target without ground your probably disappears

I think that might be it, actually...
The power supply floats its output - there's no connection between mains 
ground and the 0V output. The scope chassis and the PC PSU, on the other hand, 
do seem to ground 0V to mains ground...

I've got the PC plugged into a four-way socket strip, and the scope is plugged 
into that via a 5m 2-way socket strip (serving as a double adapter). I 
wouldn't have thought you'd get a ground loop if they were all running off the 
same mains cable though?

Thanks.
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Phil.                         | Kitsune: Acorn RiscPC SA202 64M+6G ViewFinder
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