You can not 'require' moist ground for an adequate ground... in fact you
usually have to design for the worst case and be sure you have a good enough
ground even when the soil is dead dry.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: Gary Schafer [mailto:garyschafer@comcast.net]
> Sent: Monday, January 17, 2005 17:14
> To: David Robbins K1TTT
> Cc: 'Alan NV8A (ex. AB2OS)'; 'towertalk reflector'
> Subject: Re: [TowerTalk] There's 'ground', and then there's 'ground'
>
> Yes the main reason for keeping them away from the foundation is to keep
> them in a more moist ground. The ground tends to be much dryer under the
> eves of the house.
>
> Concrete is not a bad lightning conductor but the foundation wall of a
> house with a basement will be rather dry.
>
> Lightning is in the range of DC to around 1 mhz so it is not high
> frequency energy for the bulk of it although some of it does extend
> higher. Moist ground is a requirement for a good lightning ground.
>
> 73
> Gary k4FMX
>
> David Robbins K1TTT wrote:
> > That is a convenient way to say 'keep them away from the foundation'...
> > moisture helps for low frequency and low current grounding where ion
> > conduction is the main conduction method, but does almost nothing for
> high
> > frequencies or lightning.
> >
> >
> > David Robbins K1TTT
> > e-mail: mailto:k1ttt@arrl.net
> > web: http://www.k1ttt.net
> > AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> >
> >
> >
> >>-----Original Message-----
> >>From: Alan NV8A (ex. AB2OS) [mailto:nv8a@att.net]
> >>Sent: Monday, January 17, 2005 17:00
> >>To: towertalk reflector
> >>Cc: David Robbins K1TTT
> >>Subject: Re: [TowerTalk] There's 'ground', and then there's 'ground'
> >>
> >>I have read that the ground rods should be out from the eaves,
> >>presumably (my guess) because the ground there will stay moister.
> >>
> >>Alan NV8A
> >>
> >>
> >>On 01/17/05 11:38 am David Robbins K1TTT tossed the following
> >>ingredients into the ever-growing pot of cybersoup:
> >>
> >>
> >>>Depending on the spacing of the 2 existing rods you could reduce your
> >>
> >>ground
> >>
> >>>impedance by 50% or more with 2 more rods. Maybe a LOT more depending
> >>
> >>on
> >>
> >>>the exact geometry of the situation. Lots of people make a big mistake
> >>
> >>by
> >>
> >>>driving a rod right next to the foundation, you should note that this
> >>>reduces the effectiveness of the rod because half of the circle around
> >>
> >>it is
> >>
> >>>cut off by the foundation forcing all the current to go in only one
> >>>direction.
> >>
> >
> >
> > _______________________________________________
> >
> > See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any questions and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
>
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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