When I say broad, that means outside of the RF Spectrum.
Posted on 10/21/2012 1:25:23 PM PDT by Kartographer
The first thing that we need to look at is the distinct lack of information available about EMP and its effects. Most of what we know is from nuclear tests, both American and Soviet, in the 1960s. Data and information after that period is still highly classified, so all we have to go on is what has been declassified from this earlier era of tests. However, this information, along with a few pieces of recent data, is enough to make some reasonable projections.
The second thing we need to understand is that a HEMP attack on the United States is about as bad as it gets. Experts predict that 70% – 90% of Americans would be dead within 12 – 18 months after an EMP attack. The reason for this is the extreme dependence on electricity and the delocalization of resources, like food, water and sanitation abilities.
EMP is survivable, but you need to start preparing for it now. Unlike other disasters, there is no warning or precursor, and no ability to, “finish prepping,” once it occurs. EMP is an instantaneous event. One second after an EMP attack, it’s lights out forever.
(Excerpt) Read more at thesurvivalmom.com ...
Military electronics are hardened against emp, they have layered defenses.
Being underground completely negates the need to have to worry about pin holes.
http://en.wikipedia.org/wiki/Electromagnetic_pulse
“Effects of a HEMP device depend on a very large number of factors, including the altitude of the detonation, energy yield, gamma ray output, interactions with the Earth’s magnetic field, and electromagnetic shielding of targets.”
“The three components of nuclear EMP, as defined by the IEC, are called E1, E2 and E3.”
“The E1 pulse is the very fast component of nuclear EMP. The E1 component is a very brief but intense electromagnetic field that can quickly induce very high voltages in electrical conductors. The E1 component causes most of its damage by causing electrical breakdown voltages to be exceeded. E1 is the component that can destroy computers and communications equipment and it changes too quickly for ordinary lightning protectors to provide effective protection against it.”
“The E2 component is generated by scattered gamma rays and inelastic gammas produced by weapon neutrons. This E2 component is an “intermediate time” pulse that, by the IEC definition, lasts from about 1 microsecond to 1 second after the beginning of the electromagnetic pulse. The E2 component of the pulse has many similarities to the electromagnetic pulses produced by lightning, although the electromagnetic pulse induced by a nearby lightning strike may be considerably larger than the E2 component of a nuclear EMP. Because of the similarities to lightning-caused pulses and the widespread use of lightning protection technology, the E2 pulse is generally considered to be the easiest to protect against.”
“The E3 component is very different from the other two major components of nuclear EMP. The E3 component of the pulse is a very slow pulse, lasting tens to hundreds of seconds, that is caused by the nuclear detonation heaving the Earth’s magnetic field out of the way, followed by the restoration of the magnetic field to its natural place. The E3 component has similarities to a geomagnetic storm caused by a very severe solar flare.[21][22] Like a geomagnetic storm, E3 can produce geomagnetically induced currents in long electrical conductors, which can then damage components such as power line transformers.[23]”
Even a little bit of reading would help on this topic.
This article is talking theoretical perfect EMP burst, but in a real event, the first quote is the one to remember.
“Effects of a HEMP device depend on a very large number of factors, including the altitude of the detonation, energy yield, gamma ray output, interactions with the Earth’s magnetic field, and electromagnetic shielding of targets.”
Anything within 1/4 mile of a nuclear explosion will be destroyed and won’t have to worry about EMP.
The effects of EMP can be seen over long distances, easily 1000-2000 miles under the right conditions.
I didn’t say a screen cage. now run off an play
“Anything within 1/4 mile of a nuclear explosion will be destroyed and won’t have to worry about EMP.”
Um, no, again. In fact, many military systems, including mobile are designed to survive such an event.
Yes I’m familiar with military electronics.
“now run off an play”
A little limp wristed there, are ya? Seriously, this isn’t a little 8th grade girls club where you can try to be dismissive to win an argument.
Yes I dismissed you as being a child. Anyone who seriously thinks 1/4 of a mile from a nuclear explosion is survivable is ignorant.
Unless of course you have 1800 feet of granite in between you which is actually more than a 1/4 of a mile. Even then it only protects you from the smaller weapons < 10 Mega Ton. Even the very small bombs dropped on Japan killed everyone and destroyed everything within a range larger than 1/4 mile.
My wife and I got up this morning and as we walked to our cars we did a scan of the landscape and the morning air and light, we looked at each other and I said, “we really do live in the closest thing to paradise on this planet.”
Now, if they could just repeal the state income tax, it would be the closest thing to paradise on any planet I’ve visited.
The electronics will work fine, but: a) you won't be able to recharge them and b) they won't have a network to connect to. I remember a scene from Jericho where the kids were using cellphones and Ipods in a street game with baseball bats - poor substitutes for balls, but that was about their only use.
Thanks, though, for pointing out that THE big threat from EMP isn't to our personal electronics, but to the grid. No grid means no fuel production, which means no transportation, no food being grown or transported to your local store, etc. No grid also means that our modern medical system is defunct - you will just have whatever antibiotics and sterile supplies that you have on hand, and that's it. No electronic diagnostic equipment, and most of the docs and nurses will perish along with the general population (though smart groups will make sure that those medical people - even retired - that they have are well fed). In short, EMP will destroy our society as we know it. We'll rebuild - assuming that no one else invades or otherwise impedes our progress - but the cost will be horrific.
“I’m just finishing “Adrian’s War,” the sequel to “A Distant Eden.” I recommend both books, just for the illustrations of what is probable in the event of a HEMP. Both books are available for kindles.”
I got both from a free site http://www.ereaderiq.com/ but haven’t read them yet, but thanks for the recommendation. Now that the election is almost done with, I’ll have time to read them and learn something from them.
Regarding the Kindle (or any other e-readers): I have a bunch of survival-related information on mine, and I back it up on computers and flashdrives. I will shortly be getting the Samsung Galaxy Note 2, which has removable Micro SD storage and can be used to download Kindle apps and .pdfs (unlike the iPhone 5, as I understand it). I plan to have a couple of these loaded with duplicate survival libraries - this is information that will be critical to survival and the rebuilding of society. They WILL be placed in the best Faraday cage that I can build - in hopes of useful survival. Also, the advantage to using a glorified phone as the e-reader is that it can be charged up more easily and quickly from solar chargers...which, themselves, need to be protected from EMP. I will also likely get some older technology phone that can use the Note II’s storage, and just hide that away as well. The key is to have things that are protected on a constant basis - which will augment any devices that may survive the initial EMP.
Of course, a smart enemy would hit us with an EMP weapon (or 10), then wait a week or 2 and hit us again, to fry whatever else we might have dragged out of storage and have exposed. That would be the deathblow.
So, if I build a box out of solid ferrous metal, and ground it, will if stop an EMP or not?
If I build a box out of a close knit woven ferrous metal and ground it, will it stop an EMP or not?
I have worked in labs where we tested for EMP resistance. We used a big cage made of woven metal, grounded, and it protected the equipment out side the cage. (Basically a big transformer with a kill switch inside)
I wasn't in the cage myself, programmer, not EE, but still saw the cage and knew what went on over there.
JFTR, the EEs liked to do a demo of what an EMP does to a chip by putting one in the microwave & killing it. They would also put a CD in there for a light show on a bigger scale. (note not good for microwaves, smells bad!)
I am not an EE. I only know that THEY said a microwave would work, if grounded.
Delph
It depends on many factors, you are better off than someone who is unprotected completely.
Different energies have a different range of affect depending on the altitude of the event.
If an EMP was directly above your head, you would have to have a lot more than just a solid ferrous metal box.
A solid ferrous box grounded just like a Faraday cage will serve a dual purpose, protecting you against a much broader range of potential emf.
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