In article , running dogg wrote:
Actually, the idea of terrorists detonating a nuclear bomb over the US
to wipe out solid state technology dates from 2000, when it was used as

Actually it dates from the late 1950's or early 1960's when they detonated
a bomb several hundred miles above Johnson Atoll and blew out street
lights in Hawaii 700? miles to the north.

Only about one or two percent of the bomb's energy is converted to
the EMP. It come from the interaction when the X-ray wavefront of the
explosion slams into the atoms in the upper atmosphere, and the displaced
electrons get jerked. Add in the earth's magnetic field and you end up
with a pulse generated in a pancake shaped area about 1000 miles across
(depending on the altitude of the explosion). This pulse has a very
short risetime, under 100 nanoseconds and then tails off over several
microseconds.

But the key point is that you need an antenna that picks it up.
If the antennas (intended or accidental) are short enough, they won't
collect enough energy to harm the equipment. And the equipment has to
be sensitive in the first place. Pretty much like dealing with nearby
lightning strikes.

Mark Zenier Washington State resident