[Elecraft] MY SECOND K2

[Stephen W. Kercel]

Vic:

Certainly I agree; likewise substations and skyscrapers take hits fairly 
often.

Let me qualify my comments by two clarifications:

1) You can design to survive an "average" direct hit. While the cost to do 
so can be met by commercial broadcasters, power companies, and commercial 
real estate operators, it is utterly out of reach of practically all hams.

2) Even in a commercial setup, you cannot design to be completely lightning 
proof. You can design to withstand a certain stroke current, perhaps a 
current that is higher than that found in 99.9999% of strokes in your 
region. If so you still have a one in a million chance of being wiped out, 
pretty good (if perhaps prohibitively expensive) odds, but not dead-certain 
protection.

73,

Steve
AA4AK




At 03:15 PM 9/1/2005 -0700, Vic K2VCO wrote:
>Stephen W. Kercel wrote:
>
>>BTW, you cannot really design to survive a direct hit. If your antenna is 
>>actually struck by lightning, the antenna itself will most likely be 
>>destroyed, along with the coax and the rig. Also the building will suffer 
>>structural damage.
>
>I don't think that's quite true.  BC stations survive direct hits every 
>day.  I would agree, however, that it would cost more than most hams are 
>willing to spend.
>
>You would need an antenna some distance from the building, with an 
>appropriate lightning ground system (multiple radials, each with several 
>ground rods on it) at the base of the tower.  Then you would need 
>lightning suppressors at the top and bottom of the tower for all coax and 
>control lines.  At the entrance to the building, you would need a single 
>entrance panel, through which all power, antenna, telephone, etc. lines 
>feeding the building would pass and on which were mounted the appropriate 
>suppressors for all the above.  At this point there would be another 
>ground system, bonded of course to the antenna ground system.
>
>If you had a separate building for a shack, this probably wouldn't be too 
>hard; but for a building that also serves as a home it might be difficult!
>
>
>--
>73,
>Vic, K2VCO
>Fresno CA
>http://www.qsl.net/k2vco