Jerry,
I believe lightning rods are placed on barns in order to give lightning
some place to go if a strike occurs (they are grounded thru a ground
lead). Although there seems to be varied opinion on this, I don't
think that the rod necessarily decreases the chance of strike. In fact,
if anything it may increase the odds of a strike. What it does do,
however, is lessen the odds that the strike will attach to an undesireable
part of the structure (like the wooden sides). It also provides a controlled
path to ground for the stroke energy if a strike occurs. Whatever the case,
I think the idea is to lessen the odds that all the hay, horses, and pigs
will go up in smoke. Since your tower is already a good ground rod (I
assume its made of metal and grounded properly at the base), I don't
see any benefit to adding a sharp point at the top.
Actually it brings up a good question for the lightning technology experts
on Towertalk. How come you only see lightning rods on barns and not
houses? Is that just because most barns are old, and people have stopped
using lightning rods, or is the their some other reason?
73 de Mike, W4EF.....................................
----- Original Message -----
From: "Jerry Keller" <k3bz@arrl.net>
To: "(Reflector) TowerTalk" <towertalk@contesting.com>
Sent: Saturday, May 31, 2003 5:04 PM
Subject: [TowerTalk] Length of Mast
> My 40' tower will have a 12 foot mast. I've heard it's a good idea to
fasten
> a sharp-pointed rod at the top of the mast... supposedly to reduce the
risk
> of a lightning strike....like the lightning rods I see on barns. If it's
> true, does it really help a lot? (I don't notice a lot of other hams
doing
> it, so I'm wondering)
> Jerry K3BZ
>
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