Did the counter top melt at all?
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Jim Gammon
Sent: 27 November 2013 06:51
To: [log in to unmask]
Subject: Re: Re-station ground
Hmmh, I couldn't say about that but it brought back a memory of
when I was in middle school. I can talk about this because it's
been over 40 years ago. We had a class room with metal counters,
maybe they all had them. I had found an electrical cord with a
plug on one end and bare wires on the other, a dangerous thing in
any case but especially in the hands of a kid in jr high. Well,
I plugged the cord in and touched the wires to the counter top
and man how the sparks did fly!
But, actually to be more scientific about it, to see if one wire
completed the circuit and would probably mean the countertop was
grounded, I would have had to try each wire separately on the
countertop which I may have done, but after all these years, I
don't remember. What I finally did was to tie the ends together
then give the plug to another student and have them plug it in.
You could hear the circuit vibrate in the wall for maybe seemed
like 20 seconds or so, longer than I would have expected, before
it quit for the rest of the school year. Jim WA6EKS
----- Original Message -----
From: Colin McDonald <[log in to unmask]
To: [log in to unmask]
Date sent: Tue, 26 Nov 2013 23:23:26 -0700
Subject: Re: Re-station ground
is a stainless steel countertop generally grounded to the house
electrical
system?
73
Colin, V A6BKX
--------------------------------------------------
From: "Steve Dresser" <[log in to unmask]
Sent: Tuesday, November 26, 2013 2:59 PM
To: <[log in to unmask]
Subject: Re: Re-station ground
Colin,
I'd caution against using the grounding of the electrical
outlets as a
station ground. I lived in a house where the electrical ground
of the
outlets had 150 volts which I measured between it and a
stainless steel
counter in the kitchen. It turned out that the house's
electrical system
wasn't grounded to anything in the known universe.
Steve
----- Original Message -----
From: "Colin McDonald" <[log in to unmask]
To: <[log in to unmask]
Sent: Tuesday, November 26, 2013 16:31
Subject: Re: Re-station ground
you already have a ground between the tuner and the radio via
the coax
shield...
You already have full chassis ground through the ground prong on
the AC
power.
However, to avoid RF hot spots on the chassis of your equipment,
it is
advisable to use another earth ground of some kind for your
equipment...either via a ground rod, or to the main electrical
ground of
the
house such as the city side of the water meter on the cold water
pipe, or
connected to the ground rod used by the electrical of the house
if there
is
one.
Also, having a separate ground rod just for the station is good
because
that
can also be used for both RF and electrical ground and will help
in the
case
of a nearby lightening strike etc.
You need to use a ground bus, and have a wire from each piece of
equipment
connected to that common bus...do not daisy chain the grounds
together.
In
other words, your grounding has to be paralel, not series.
If it's electrical ground, the wire length doesn't matter at
all...but if
you are going after an RF ground, the length of the ground wire
may, if
you
are using a non-resonant antenna, or latter line or long wire
and a
tuner,
effect the tuning of the antenna.
Often an additional ground for the station equipment is not
necesary as
the
AC ground takes care of it, but sometimes you may need it if you
find you
are having issues with RFI in your audio, or excessive noise on
receive
or
if you are causing RFI to other electronics in the house or with
your
neighbors.
73
Colin, V A6BKX
--------------------------------------------------
From: "Mike Ryan" <[log in to unmask]
Sent: Tuesday, November 26, 2013 1:10 PM
To: <[log in to unmask]
Subject: Re-station ground
So if I have a ground wire running from my ATU's ground stud to
the back
of
the rig's ground stud, considering my rig has a built in power
supply
and
a
3 prong plug, this will be fine?
Mike
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