> measures <2@vc.net> wrote:
> A typical lightning strike is c. 100kA. This is beyond the capability of
> >spark plugs.
>
No doubt. It's also beyond the capability of open wire line, coax, 2"
aluminum booms, and #4 copper.
But once the arc jumps across the plug gap to ground it doesn't matter
whether the plug can handle it or not - at 100kA won't the subsequent path
be via ionized air? And then won't the spark plug thingy have done its job?
It's my understanding that the spark plug idea is primarily to prevent
burning your house down, not to guarantee that your equipment won't get
zapped. Disconnecting radios during storms is still highly recommended. Even
then, if you take a direct (100 kA) hit in very close proximity you might
well have toasted electronics just through high induced currents - there are
documented cases of this happening.
73,
Doug, KF4KL
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