Tom it sounds like you are on target. I spent 35 years in the electrical
field and can say absolutely that lightening can do anything. All we can
do is try to do things that minimizes potential differences. One is
draining the difference off to ground before it gets high enough to strike.
Many of the seminars and trade journals preached single point grounding to
prevent ground loops in computer equipment. That does include isolated
grounds running clear back to the point of service entrance. The service
entrance of a home is that single point. . Please note that towers
antennas and radio equipment is covered by the National Electric Code.
First the electric power system in a home is required to have a single point
ground. Normally a ground rod and any metal water pipes or other metal in
the home is bonded to it. The exception is gas piping. Although honestly
through the furnace sheet metal it is grounded there. Any deliberate
bonding of gas pipe to the electric is prohibited. Some type of dielectric
union may be required in the gas pipe now, don't know. Antennas, towers and
such needs to bonded to the electric service point. In my case they are
some 40 feet apart. So I have a ground rod under my 2 meter antenna another
under the hf antenna and the three are bonded together with number 2 copper
wire. Multiple ground rods are acceptable as long as they are bonded
together. Note I am talking about electrical safety grounding. Of course
any lightening arresters belong outside on or very close to the mast and
attached to a earth ground close by. Most radio equipment is technically
powered by 12 volts except for power supplies so the radio equipment grounds
to the closest point which in this case is the closest ground that is part
of the single bonded point. I know they call for copper straps and such to
work as the rf ground system and if one is going all the way buried copper
sheet metal, but all this needs to be bonded to the closest point of the
single point ground. Hopefully this is not too much rambling, but just
remember the National Electric Code is for our personal safety and does help
protect equipment. Someday I hope to get disconnect or shorting switches to
remove my antenna from the radios but for now I either unhook or buy the
insurance.
Ron
KD0HOY
by.
----- Original Message -----
From: "tom behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, June 15, 2011 9:15 AM
Subject: Re: grounding question
> Hi, all:
>
> This is a very interesting discussion, on which I'm sure there will be
> many
> varied opinions.
>
> So, I would like to describe my set-up, to see if I'm doing ok?
>
> At the home qth, I have a single 8-foot copper ground rod which represents
> my common ground point. I have a 10-gauge grounding cable running from
> the
> ground rod, to the common ground lug on the outside of my MFJ feed-through
> window pannel to which all of my antennas are connected. Then, I run
> separate grounding cables from the inside portion of that same common
> ground
> lug on the window feed through panel to each piece of equipment--i.e. rig,
> manual tuner, amplifier, etc.
>
> When lightning threatens, I disconnect all antenna leads from the inside
> connectors on the window feed through panel, and unplug everything.
>
> Am I ok here, or am I courting disaster?
>
> 73 from Tom Behler: KB8TYJ
>
>
>
> ----- Original Message -----
> From: "Tom Brennan" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Wednesday, June 15, 2011 4:45 AM
> Subject: Re: grounding question
>
>
> Wel, Pat, that was my thought but someone had told me it didn't matter so
> I
> thought I'd ask as there are a lot of you guys who have been hams much
> longer
> than me and tend to be a great resource on just about any ham question.
>
> Thainks.
>
> Tom
>
>
> Tom Brennan KD5VIJ, CCC-A/SLP
> web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html
>
> On Tue, 14 Jun 2011, Patrick Gormley wrote:
>
>> Date: Tue, 14 Jun 2011 22:32:41 -0400
>> From: Patrick Gormley <[log in to unmask]>
>> Reply-To: For blind ham radio operators <[log in to unmask]>
>> To: [log in to unmask]
>> Subject: Re: grounding question
>>
>> At my station here in Frostburg, my antennas are grounded in one place
>> and
>> my station has its own 8-foot ground rod. 73- pat kk3f
>> It's preferable to have separate grounds to minimize the possibility of a
>> ground loop.
>>
>> --------------------------------------------------
>> From: "Tom Brennan" <[log in to unmask]>
>> Sent: Tuesday, June 14, 2011 10:24 PM
>> To: <[log in to unmask]>
>> Subject: grounding question
>>
>> > I'm just setting up my ts2000 after being off the air for the past
>> > year.
>> > I've a
>> > breakout box for cables and such. I'll run a ground wire through the
>> > box
>> > out to
>> > an 8ft grounding rod. My question is this -- I have one of those gas
>> > lightning
>> > arresters. It will attach to the breakout box and the antenna cable
>> > will
>> > attach
>> > to it. It is to be grounded. When I ground it is there any good
>> > reason
>> > that it
>> > should have a ground separate from the radio or can they both be
>> > grounded
>> > to the
>> > same ground rod?
>> >
>> > Tom
>> >
>> >
>> > Tom Brennan KD5VIJ, CCC-A/SLP
>> > web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html
>> >
>>
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