[Elecraft] Ligntning protection

[FredJensen]

Lightning is about as predictable as your average teenager.  It is very 
[very!] common for cloud-to-ground strikes to start with a 
ground-to-cloud "leader."  You can't see it and it happens fairly fast 
[but nowhere near as fast as the main strike].  It builds an ionization 
path when the main strike then follows from the cloud to the ground ... 
at least part-way.

So, one could surmise that a ground rod connected to your mast would 
offer a desirable path for the leader current and thus "attract" a 
strike.  Whether or not this will happen depends on where the ground 
charge has accumulated [usually but not always under the guilty cloud], 
whether or not your ground rod actually *is* a desirable path, what else 
is around your mast, and a host of other unpredictable things.  A rod 
stuck in the earth makes a very problematical connection to "ground."

The fact that the apex of the mast is not connected to your antenna is 
not relevant for a strike, although it is relevant for precip static.  
If a few megavolts decides to land on your "grounded" mast, it will all 
become connected and a few microseconds later, be vaporized.

73,

Fred K6DGW

On 4/21/2011 7:27 PM, Steve Ellington wrote:
> 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.