The ground you put in the concrete i.e. the rebar would not be optimum.
Concrete is a very good insulator. The common 8' copper clad steel grd rod
is hard to beat. "The more the merry" . also single point ground system.
Try to get the neutral in your panel box at near the same potential. Plug a
one wire connector to the ground connector of a outlet an connect it to your
station ground wire. You do not want different potentials during a lightning
strike. Imagine you were standing five feet from a tree that is about to
get a direct lightning hit. If you had your feet 20 or thirty inches apart
the voltage at you left foot would or might be 100,000 volts as the current
dissipates the father it gets from the tree your right foot may have a
potential of 30,000 volts the difference is 70,000 volts that would blow
thru a pair of nike tennis shoes and you with not much problem. If your
station is plugged into a grounded outlet that runs 100' to your service
entrance and you have a separate ground rod out your window and a 10' wire
there will be difference in potentials . REMEMBER SINGLE POINT GROUND
----- Original Message -----
From: "Geo Clute W7LFD" <gclute@attbi.com>
To: "AMPS" <AMPS@contesting.com>
Sent: Monday, April 15, 2002 5:28 PM
Subject: RE: [Amps] RF Ground for 2nd Floor
> http://www.polyphaser.com/datasheets/PTD1016.pdf This seems to be a very
accurate and valid discussion of grounding and protection from lightning
strikes.
>
> Here, on the second floor of a tri-level house my office, radio shack is
above the ground about 12 foot to the office 2nd floor. Below me is the
garage. Located below the office floor about 4 ft and to the right about 1
foot is the 250 amp electrical panel. I drilled through the floor and ran 6
gauge insulated solid copper thru the panel to the outside. Then followed
the electrical panel ground to the utility company's ground rod. Clamped
and soldered. I ran 220 line from the panel up through the same opening.
Then poured a 6 inch thick concrete pad at the side of the house (40'X12')
and tied the ground rod to the rebar in several places.
>
> Not certain this is right, however it seems to work for the last 26 years.
For VHF work I'm not sure anything this far away from ground will work
properly.
>
>
> Geo W7LFD
>
> Kim writes:
> But, how best should I handle a station that's up in the air with no hope
of a ground run short enough to constitute a good RF ground?
>
> _
>
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>
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