[Elecraft] Lightning concerns: Was: K4 Remote: My QTH vs. a friend's, many miles to the north

Jim Brown jim at audiosystemsgroup.com
Tue May 7 22:56:37 EDT 2024


On 5/7/2024 4:46 PM, Al Lorona wrote:
> In spite of all the grounding and bonding and spark-gapping and
> everything else you may have done, are you confident enough that you
> would trust it all and let the direct hit happen? Or would you
> disconnect everything -- you know, just in case?
> 
> I suspect every last one of us would disconnect absolutely everything
> that we wanted to save. It's good to be prepared, but we all know that
> significant risk always remains no matter what we do.

A major misconception about lightning is that antennas are the primary 
target. Nothing could be further from the truth. Lightning comes in on 
telco, CATV, power lines, etc. IEEE says that 3KV can be induced on 
wiring inside our homes. If ALL interconnected stuff has their chassis 
bonded, it stays outside the box. If not, interconnected wiring takes it 
inside the box and fries stuff.

It is ALL about grounding and bonding of ALL interconnected stuff.

Example -- years ago, a professional colleague who's not a ham and had 
no antennas had everything in his home office Ethernet fried, because 
all of the gear was plugged into different outlets, all "protected" by 
MOV strips. Remembering that lightning is an RF event, the only bond 
between widely separated, but interconnected gear, was that Ethernet, 
the chassis of each piece of gear rose to a different potential 
depending on how much current the MOVs dumped into the green wire 
feeding it, and the difference in potential, seen only by the Ethernet 
stuff, fried it.

Years ago, W8JI made a point of saying he never disconnects stuff. 
That's also my practice.

73, Jim K9YC




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