Jeffrey Madore wrote:
> In my experience with grounding as lightning protection, a very important
> aspect is that everything be kept at the same potential. All grounds need to
> be common with the electric service ground. The tower, metalic plumbing, and
> anything metalic of any length, must be bonded together such that the entire
> grounding system is at a common potential. Then added to that ground system
> should be several electrodes. What is often not expressed, is that a good
> grounding system will greatly lessen the possibility of a lightning strike
> by constantly discharging the rapidly building electrostatic potential
> during a storm. An ungrounded wire antenna, in my experience, is an open
> invitation for a lightning strike.
>
>
It is best to bond everything together. However grounding does not prevent a
lightning strike. There is nothing that will prevent a strike. It is impossible
to bleed off the charge buildup. The earth can supply the charge many many times
faster than it can be bled off. It is an old wives tale about bleeding off the
charge. There are even some manufacturers that sell some brush type dissipation
devices that are supposed to bleed the charge off by the many sharp points. They
don't work.
As a matter of fact an ungrounded antenna has a slightly less chance of being
hit than a grounded one. But it is not wise not to ground it. When it does get
hit if it is grounded you have some control where the current goes. If it is not
grounded you have no control where the current goes.
73
Gary K4FMX
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