----- Original Message -----
From: "David Lisney" <g0fvt@hotmail.com>
> G3JVCs approach to this seems eminently reasonable to me, albeit probably
> expensive!
>
> A weakness in my existing layout is of course that if I get a live to
> earth
> short anywhere in my property some of that fault current will pass via the
> ground of my HF transceiver to my RF ground. I have a current balun
> arrangement which should help effectively isolate the two earths at RF to
> some unknown extent but it will have negligible impedance at 50hz.
The current balun on your feedline should help keep the RF noise
from the AC mains from getting coupled into your antenna.
> If I ignore boring wiring regs I could arguably rely on my RF ground as a
> safety ground for the ham gear, however I am sure the delta connected
> capacitors in the mains input to the radio mains power supply will carry
> RF
> noise to the chassis....
>
> Since I have very little confidence in the low impedance of my RF ground
> (the gardener dug up some of it) I cannot trust it as a safety ground at
> the moment... however the more I think about it the more I am convinced
> that
> G3JVCs solution is correct, to establish a good quality trusted "clean"
> safety ground independent of the grid and to achieve galvanic isolation by
> the use of an isolating transformer.
K9YC has reported that several of his fellow hams in the Chicago
area have had good success reducing RF noise by placing very
large Fair-Rite products #31 clamp on ferrites beads over their
AC mains drop.
73, Mike W4EF................................................
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