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Fred Townsend

Re: Ligntning protection

" Question:
Does grounding your tower or metal mast increase the likelihood of it being
hit by lightning?"
Answer: One would hope would hope so.

There are several theories of lightning protection. Before I comment on
those methods let me ask. Would you rather the lightning strike your antenna
or your mast? If the antenna is struck your coax and everything attached or
(usually) anything near your coax, is hosed. Even disconnect switches do not
always protect. Conclusion it is much better to take the strike on the mast
but if you can prevent the strike you are still better off.

As a young boy I helped my grandfather install lightning rods on houses.
There were two kinds of rods. One had a sharp point at the end and the other
a big ball. The ball rods were considered to be superior because they
usually took more strikes. Now we know that the pointed variety is superior
because they bleed off charge preventing strikes.

Take a close look at the popular video making the rounds showing the guys
climbing a 1700'? tower. Did you notice all the sharply pointed objects on
arms surrounding the top? Those are there to bleed off the charge.

Final conclusion:

Ground the mast and put a pointed lightning rod at the top.

de Fred AE6QL.

-----Original Message-----
From: Steve Ellington [mailto:[hidden email]]
Sent: Thursday, April 21, 2011 12:28 PM
To: Fred Townsend; 'Randy Moore'; [hidden email]
Subject: Re: [Elecraft] Ligntning protection

Question:
Does grounding your tower or metal mast increase the likelihood of it being
hit by lightning?
I have a 50' metal mast holding up the center of a dipole. No antenna
contacts the mast and the ant. is supported by rope. Should I drive in a
ground rod just for the mast? If I do, would lightning be attracted to it
then? It just seems like I'm inviting a hit by grounding it.

Steve
N4LQ
----- Original Message -----
From: "Fred Townsend" <[hidden email]>
To: "'Randy Moore'" <[hidden email]>; <[hidden email]>
Sent: Wednesday, April 13, 2011 12:19 PM
Subject: Re: [Elecraft] Ligntning protection

> Randy:
> I can not speak to your local building codes but the rule of thumb is
> lightning does not like to travel horizontally. That doesn't mean it won't
> happen but usually lightning seeks the shortest path to ground. That
> suggests you should connect to the closest ground (exception: any fuel
> line).
> If possible I would drive my own ground rod below the shack and use the
> garage ground as well. There is no penalty for extra grounds.
>
> 73
> de AE6QL, Fred
>
> -----Original Message-----
> From: Randy Moore [mailto:[hidden email]]
> Sent: Wednesday, April 13, 2011 8:15 AM
> To: [hidden email]
> Subject: Re: [Elecraft] Ligntning protection
>
> Sorry if someone has already asked this. My shack is on the second floor
> of
> my home and is on the opposite corner of the house from where the
> electrical
> power entry and ground are located. However, the electrical panel is in
> the
> garage right below my shack. Can I connect my shack ground to the panel
> ground instead of running a ~200' long line to the electrical ground on
> the
> other end of the house?
>
> Tnx es 73,
> Randy, KS4L
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

______________________________________________________________
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Steve Ellington

Re: Ligntning protection

Then I should charge my neighbors for protecting their houses from
lightning.

Steve
N4LQ
----- Original Message -----
From: "Fred Townsend" <[hidden email]>
To: "'Steve Ellington'" <[hidden email]>; "'Randy Moore'"
<[hidden email]>; <[hidden email]>
Sent: Thursday, April 21, 2011 4:04 PM
Subject: RE: [Elecraft] Ligntning protection

>" Question:
> Does grounding your tower or metal mast increase the likelihood of it
> being
> hit by lightning?"
> Answer: One would hope would hope so.
>
> There are several theories of lightning protection. Before I comment on
> those methods let me ask. Would you rather the lightning strike your
> antenna
> or your mast? If the antenna is struck your coax and everything attached
> or
> (usually) anything near your coax, is hosed. Even disconnect switches do
> not
> always protect. Conclusion it is much better to take the strike on the
> mast
> but if you can prevent the strike you are still better off.
>
> As a young boy I helped my grandfather install lightning rods on houses.
> There were two kinds of rods. One had a sharp point at the end and the
> other
> a big ball. The ball rods were considered to be superior because they
> usually took more strikes. Now we know that the pointed variety is
> superior
> because they bleed off charge preventing strikes.
>
> Take a close look at the popular video making the rounds showing the guys
> climbing a 1700'? tower. Did you notice all the sharply pointed objects on
> arms surrounding the top? Those are there to bleed off the charge.
>
> Final conclusion:
>
> Ground the mast and put a pointed lightning rod at the top.
>
> de Fred AE6QL.
>
> -----Original Message-----
> From: Steve Ellington [mailto:[hidden email]]
> Sent: Thursday, April 21, 2011 12:28 PM
> To: Fred Townsend; 'Randy Moore'; [hidden email]
> Subject: Re: [Elecraft] Ligntning protection
>
> Question:
> Does grounding your tower or metal mast increase the likelihood of it
> being
> hit by lightning?
> I have a 50' metal mast holding up the center of a dipole. No antenna
> contacts the mast and the ant. is supported by rope. Should I drive in a
> ground rod just for the mast? If I do, would lightning be attracted to it
> then? It just seems like I'm inviting a hit by grounding it.
>
> Steve
> N4LQ
> ----- Original Message -----
> From: "Fred Townsend" <[hidden email]>
> To: "'Randy Moore'" <[hidden email]>; <[hidden email]>
> Sent: Wednesday, April 13, 2011 12:19 PM
> Subject: Re: [Elecraft] Ligntning protection
>
>
>> Randy:
>> I can not speak to your local building codes but the rule of thumb is
>> lightning does not like to travel horizontally. That doesn't mean it
>> won't
>> happen but usually lightning seeks the shortest path to ground. That
>> suggests you should connect to the closest ground (exception: any fuel
>> line).
>> If possible I would drive my own ground rod below the shack and use the
>> garage ground as well. There is no penalty for extra grounds.
>>
>> 73
>> de AE6QL, Fred
>>
>> -----Original Message-----
>> From: Randy Moore [mailto:[hidden email]]
>> Sent: Wednesday, April 13, 2011 8:15 AM
>> To: [hidden email]
>> Subject: Re: [Elecraft] Ligntning protection
>>
>> Sorry if someone has already asked this. My shack is on the second floor
>> of
>> my home and is on the opposite corner of the house from where the
>> electrical
>> power entry and ground are located. However, the electrical panel is in
>> the
>> garage right below my shack. Can I connect my shack ground to the panel
>> ground instead of running a ~200' long line to the electrical ground on
>> the
>> other end of the house?
>>
>> Tnx es 73,
>> Randy, KS4L
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>
>
>

123