[R-390] Ham Shack Grounding Help!!!!

Fri, 21 Jun 2002 08:38:39 -0400

One should never rely on the outlet ground, there are just too many
variables.......
My station ground is based on the Handbook model.
A 1/2 inch copper pipe is mounted under the desk and braid is run from the
pipe to EACH piece of equipment.  A heavy wire is run from the copper pipe
to the earth ground system.
On installation, the ground braid is connected to the chassis before the
radio is plugged in.

As an additional safety feature, the Shack outlets are connected to a DPDT
wall switch.  In the off position, all radios are electrically dead......

Jim

----- Original Message -----
From: "Dan Merz" <[email protected]>
To: "Roy Morgan" <[email protected]>; "R-390 List" <[email protected]>
Sent: Friday, June 21, 2002 01:34
Subject: Re: [R-390] Ham Shack Grounding Help!!!!

> Roy/Kim,  I can agree with the 60 v normal when there's no grounded
outlet - I
> have pretty modern wiring in my home but one day not too long ago
discovered  60
> volts chassis to ground even though it should have been zero.  I
discovered this
> by   rf noise associated with touching a wire from an external ground rod
located
> outside the house to the radio chassis,  and then measuring about 60 volts
ac
> between the chassis and the ground wire.    It took me awhile to discover
that on
> the leg of my wiring where I have my radios there was no ground coming to
the 3
> prong outlet or to any of the several other outlets on the same circuit -
easily
> detected by plugging in one of the circuit checker gadgets - but not so
easy to
> remedy.  Fortunately I was able to get into the junction box where the
problem
> originated (conveniently left somewhat visible by the previous owner) and
found a
> ground wire that was not firmly connected to the bundle of ground wires
connected
> there.  Too many connectors in an undersized wire nut and with no room to
tighten
> it sufficiently !!  I fixed that by better type of connection and the 60
volts
> went away.   I feel safer now.  I guess if  one of those caps( the one on
the hot
> side)   that put the 60 v on the chassis happens to short,  I'll now be
saved by
> my circuit breaker or radio fuse rather than taking the potentially lethal
> current myself if I happen to be grounded.       Dan.
>
> Roy Morgan wrote:
>
> > At 11:21 PM 6/20/2002 -0400, you wrote:
> > >I have received lots of good info that I can use to help eliminate my
noise
> > >problems.  I was out all day today so did not get to follow up on any
of
> > >this.  Yesterday however I did do one check and it did not look good.
There
> > >is 60 v. from the chassis of my radio to the cold water pipe.
> >
> > Standard condition.
> > Caused by NORMAL operation of the line filter capacitors.
> > GROUND your radio to the cold water pipe, PLEASE.
> > Do not use any ground fault interruptor outlets.
> >
> > >  Not good at
> > >all.  I am going to get an electrician in here as soon as possible to
see
> > >what we are going to have to do to fix that.
> >
> > That is cused by the RADIO line filter. NOT by the electrical system in
> > your house, except that you have ungrounded outlets.
> >
> > Roy
> >
> > Roy Morgan
> > K1LKY since 1959
> > 7130 Panorama Drive, Derwood MD 20855
> > 301-330-8828 home .... 301-975-3254 work
> > [email protected]
> >
> > _______________________________________________
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