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Old August 12th 04, 05:07 PM
Richard Clark
 
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On 10 Aug 2004 21:20:29 -0700, (Private)
wrote:

Thank-you for the advice to this point. I think I will invest in the
rotator cable ground. Not sure what to do about the lightning choke.

I don't mind replacing the antenna/mast if I receive a direct
lightning hit, I just dont want to turn be fried to a crisp.....

Lloyd


Hi Lloyd,

Of the advice offered, out of the dozen or so comments, only the
addition of radials and grounding of peripheral equipment made any
sense to your already extensive installation. Adding "more" rods
sounds like hail Mary solutions. I would bet almost every house for
10 miles around you survives quite well with one.

Sure, few if any sport towers, but lightning in the vicinity is not so
choosy as to miss every house, building, or power pole simply because
they are not radio amateurs.

I also note the complete absence of discussion about the Code. All
grounds must be bonded (clamped, not screw attachment nor
solder/brazed) with a continuous wire (no breaks or splices). I also
note some rather bizarre descriptions of how chokes work (and to add
that they are not used by Hams is simply ignorance or the choice to
illustrate with poor examples).

I would suggest you mine the archives of rec.radio.amateur.antenna for
two correspondents: Richard Harrison, KB5WZI for thousands of
commercial and amateur tower installations over a career spanning 50
years (you will discover half to two thirds of suggested
embellishments are immaterial fluff); and Reg Edwards, G4FGQ for the
topic of successful ground rod application (notable in that laying
them horizontal is just as good, if not better).

As to your last comment about getting fried. You should examine that
illusion and recall that it brings voltage to mind, not current.
Voltage comes from two mechanisms common here, impedance and
resistance (the lightning strike is considered to be from a constant
current generator willing to present any potential necessary to
preserve flow). A sharp bend in a conductor is one source of
impedance change for the bad - so graceful sweeps are preferred where
you want to change direction. I note the irony of discussion where
chokes are used to build voltage (power being equal to I·E and current
being constant guarantees a build up of power beyond what would have
been suffered) to guarantee spark discharge elements firing (I suppose
so, but this sounds like Advertising Copy to sell spark discharge
elements). Most successful solutions offered here for years and years
all have the common goal of burying the lightning stroke's current
into the soil as soon as possible without any impedance to its path.
If you research the archives for low resistance paths of lightning,
you will find out how little total power is suffered in a strike
(don't fall for the monster under the bed stories of a gazillion volts
at a bajillion amps).

73's
Richard Clark, KB7QHC