[kwlug-disc] Grounding for antenna

[Paul Gallaway]

Sorry for the email just sent to the other discussion. Had written the
bulk of it yesterday but didn't see this new discussion until after
sending it out this morning. Seems like you've got it all covered.

Here's an example of the post hole hammer that I used:
http://www.allamericanrentals.com/rentalRates.php?subPage=7&item=14

I used a coax ground block and surge protector. Those surge
protectors/arrestors are a consumable metal oxide (MOV, form of
resistor) that degrade over time from use (e.g. surges, heat?). Like
your strip plug surge protector, when they are done, they are done. If
it's picking up all the dribbles of static and discharge coming
through and something big comes down the line, the MOV surge protector
may not have enough (resistance?) left to disperse all the energy (if
it ever did, lightning is a lot of joules no matter how many 000's are
on the surge protector label!). If there were a lightning induced
energy travelling down a wire I would prefer it not come inside my
house. The ground block, along with the grounded antenna, may not
prevent that entirely, but it will bleed more of the energy away,
perhaps reducing the energy entering the house to something the surge
protector can handle. Obviously I've only picked up enough about this
stuff to kind of understand what's going on, which may barely be
enough to explain it.


On Fri, Jun 13, 2014 at 9:11 AM, John Johnson <jvj at golden.net> wrote:
> Agree. But in reality even 00 gauge wire will not dissipate the charge or
> handle the current from a direct lightning strike.
> The 14 GA wire may, however, allow a light discharge to help prevent the
> build up of a much larger charge.
>
> This is part of the reasoning behind lightning rods, i.e. dissipation of
> charge vs direction of a direct strike.
>
> http://en.wikipedia.org/wiki/St._Elmo%27s_fire
>
> JohnJ

This is consistent with my incomplete knowledge as well. I just don't
have the experience/knowledge to recommend #14 over #00 for this
purpose. Some of the lightning energy will travel through, but
possibly not much of it. In my experience, people don't like being
told that no matter what they do, lightning is just going to carry on
it's way down the wires because there's SO much energy it can't be
dissipated to one ground or one surge protector.

~pAul.

all good things, all in good time...