To: <towertalk@contesting.com>
>Date: Fri, 16 Apr 1999 08:48:29 -0400
>From: Dave Jordan <wa3gin@erols.com>
>
>Why can't a person simply run a ground wire from the top
>section/mast of the crank-up down along with the coax and
>terminate the wire to the ground system at the base?
>
>===================
You _can_ do that. But until the surface area of the ground wire
and coax shield are larger than the surface area of the tower
structure, the tower will still be carrying the majority of the
stroke current.
73, Eric N7CL
>
>Bob Wanderer wrote:
>
>> The conductor running down the inside of the tower to ground
>> is unnecessary. It carries maybe 10~15% of the total current.
>>
>> However, there is higher resistance between two sections of a
>> crankup which could benefit from straping the two sectiuons
>> with copper strap. The problem is then how do you crank the
>> tower down? If you make the straps long enough to allow crank
>> down, they will flap in the wind. Making them short jumpers
>> obviates the convenience of the crankup. I guess you have to
>> decide which situation is the more tolerable.
>>
>> 73,
>> Bob AA0CY
>>
>> ----------
>> From: David Leikis[SMTP:dlleikis@deseretonline.com]
>> Sent: Sunday, April 11, 1999 9:40 PM
>> To: towertalk
>> Subject: [TowerTalk] Lightning protection grounding
>>
>> Hello,
>>
>> I have seen many recent postings concerning grounding methods
>> and saw one that stated to run a ground conductor up the mast
>> to the final section (and the others as well) to prevent any
>> high resistance points along the way through the joints.
>>
>> My question is this: I am erecting a self-supporting crankup
>> and am concerned about the sliding joints of the installation.
>> It seems as though these would definitely be high resistance
>> and would need this more than any other. What is a
>> recommended method from those that may have done this before?
>> We can have some pretty severe storms here and I am positive
>> (or negative) that lightning charge dissipation should be
>> 'high' on my list.
>>
>> Dave KG7EW
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