100 foot tower needs at keast a 100 foot radius grounding"circle".
Do not use wire for any ground since wirew does not have much surface
area. Grounding straps like 1'8' by 4 pluss inches is good for each
ground point. Plenty of surface area.
Use many many rods along the radi. I use 36. every 10 degrees, for the
first 20' from the tower. After that its 72, every 5 degrees for the
remainder.
>From the tower's center, every 20 feet is a circle is the grounding buss,
1" x 6" . Where the radi cross the circle is a 20' ground rod. If it is
solid rock, there is a 24" hole drilled to the depth and the proper
chemicle placed in the hole, the rod is incerted. At the cross points of
the Radi, Circle buss and rod all is poly phased.
The support cabling also is tied to the grounding buss.
People may say that method is an overkill but I have seen too many
problems with non proper grounding methods.
As soon as I can I will place the "Grounding" file in the file section of
this group.
Also, do not run the coax on the outside of the tower like those cell
phone dummies does. Lightning uses the "Skin Effect" to travel from top
of the tower to ground. Anything on the side is subject to damage.
Also , do not place any antenna on top of the tower, hats inviting
problems. Instead, place static dischargers on top.
Also, ground the shields of the coax to the tower every ten feet as it
travels in the tower. As well, ground the coax as it enters the building
on the outside. Pass the coax through a copper shield, as in a window,
then ground all equipment inside, the ground wire is not big enough on AC
equipment.
On my brother's tower, I was at the 300' level and it took a direct hit,
I felt nothing, nothing was damaged, not even a light bulb.
As a lkightning researcher, I have been studying since '74, I have seen a
lot of damage to towers and equipment, those that were not poperly
grounded.
Hopes this helps and I know its a lot to do but the cost of the grounding
equipment, busses, and rods, is a lot cheaper than a life or radio
equipment.
Edgar McKinney - kb8qeu
nuts4tools wrote:
> I think i am going to put up a tower already have one just 100 footer
> but was looking for a good book to make sure I grounded it right and
> just to see what I might not have thought of . Do you guys know a good
> one ? . Thanks
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