In article ,
Johnny B Good wrote:
I have a dedicated AV radial circuit here. With the earth for that going
light back to the house earth. Not sure that bit makes any difference,
though, but no big deal when installing it.

It shouldn't. Assuming you only have a single safety earth connection to
the common signal ground return, the whole thing could be left to float
at whatever induced mains voltage happens to occur (including half mains
from filters or even a full contact to the live). It won't make any
difference although I'd be rather leery of actually touching any of the
kit if bringing your hand to within close proximity generates even the
slightest hint of mains hum.

Can you run that by me again? You can obviously get a potential difference
between two earths when any current flows. Like say between the earth to a
socket and the one to a light switch in the same room.

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*WHERE DO FOREST RANGERS GO TO "GET AWAY FROM IT ALL?"

Dave Plowman London SW
To e-mail, change noise into sound.