# After EMP attack



## Frost (Nov 8, 2012)

I accept that a fiscal zombie shtf is more likely, but I tend to take the plan and expect a few steps worse.
the logic is this.
you invite me to a party. I expect Im going to be the only one to show up, the food sucks the music sucks and I hate wasting my time that night. 
If it IS that bad, I cant be let down.
if it is NOT that bad, GREAT!

So. I am looking to assume (yea yea) that there is a EMP (electromagnetic pulse Pulse) attack, all the electronics will be useless. the smaller "micro" will be fried. powered off or not. 

As I understand car batteries will work. (chemical reaction)
most car parts will function minus the electrical aspect.

so my question is...
If I place a alternator inside a Faraday cage, could it be used as a power generator? (yes hand crank or attach to a bike wheel.)

or is there a better solution? I am expecting to need to recharge some of the stuff that I plan to "stash" in a Faraday cage. 
I.E. rechargeable batteries, cellphones (if they work) GPS Etc etc etc..
Thank you in advance.


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## kejmack (May 17, 2011)

Edit: read the question wrong. Ooops.


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## FrankW (Mar 10, 2012)

Frost said:


> 1) that there is a EMP (electromagnetic pulse Pulse) attack, all the electronics will be useless. the smaller "micro" will be fried. powered off or not.
> 
> 2)As I understand car batteries will work. (chemical reaction)
> most car parts will function minus the electrical aspect.
> ...


1) That book "one second after" really messed up a lot of folks with misinformation.. 
Car ECU will NOT be fried if they are switched off!
Only some percentage ( likely low %age) or running car ECUs wil be fried in case of an EMP attack.

ECU's arewhat I like to call semi-hardened. This is since they are 100% hardened against EMI (Electromagnetic inteference) from the 100 amp alternator spinning 2 feet from it all the time they run. Is EMI as bad as EMP? Of course not ,but they are harded to withstand the afdmittedly much lighter, EMI a lifetime. .

This is the reason EMP has little effect on vehciles ECU's (while other electronic systems may be destroyed especially while turned on)
Practically this means, that many, perhaps even the great majority of running Cars, will not get their ECUs fried in EMP.
And 100% of switched off cars, trucks, and even some swtched off home computers will still be working.

2) yes.

3)No need or afaraday cage. but yes you if you cna spin an alternator ( say you take it out an attach to a stationary bike) you can charge car batteries.

These in turn via inverters can charge GPS or home laptops ( which may be full of prepping and how to pdfs)


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## mosquitomountainman (Jan 25, 2010)

There's a lot of controversy regarding an EMP's effect on automobile elecrtronics. In answer to your question though: an alternator secured inside a Faraday cage shoule be okay after and EMP. Being an alternator you'll have to have some source of electricity (at least a partially charged battery) to excite the coils in the alternator before it will charge. If you can find an old generator they have permanant magnets and don't need an outside power source to work. 

If all you're worried about is cell phones, GPS units, etc. I'd be more inclined to store a small solar powered unit designed just for such appliances or batteries.


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## Tirediron (Jul 12, 2010)

A faraday caged alternator should be ok after what ever frys electronics (I do not agree with BlueZ on the non threat of emps) BUT automotive alternators are not very good at returning manual effort, partly because they power their own field ,after being exited like MMM said. a better bet would be a small 12V perminant magnet motor , like a heater blower motor, more out put for the physical effort. and it is going to take a lot of physical effort to recharge a battery from a low state. But it is a good idea.


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## *Andi (Nov 8, 2009)

fiscal zombie shtf ~ How so ???


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## Frost (Nov 8, 2012)

*Andi said:


> fiscal zombie shtf ~ How so ???







Every great nation or empire that has ever existed as Rome, had fallen like Rome. Our Government is full of corruption, our countrymen believe that they should receive food home and money just for breathing. While we the slaves do all the work. (I get less than 10K a year and I pay almost %30 in taxes)


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## *Andi (Nov 8, 2009)

If you say so ...


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## emilnon (May 8, 2012)

Frost said:


> Video Link:
> 
> 
> 
> ...




I agree about the state of the country... But I don't think that answered Andi's question. I was confused too. Where do the zombies come in here? Or are you refering to the unprepared as zombies? Or...?

*note- I learned something new about cars, thanks y'all!


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## oif_ghost_tod (Sep 25, 2012)

emilnon said:


> I agree about the state of the country... But I don't think that answered Andi's question. I was confused too. Where do the zombies come in here? Or are you refering to the unprepared as zombies? Or...?


I think he's using zombies metaphorically for people who blindly follow, lol.

See also: 'sheeple', 'the herd', 'the mainstream', 'Future victims of America'.

Help me out here....

BlueZ has a good post on EMP check that out as well


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## Frost (Nov 8, 2012)

emilnon said:


> I agree about the state of the country... But I don't think that answered Andi's question. I was confused too. Where do the zombies come in here? Or are you refering to the unprepared as zombies? Or...?
> !


Umm yea... 
unless... you all think. that the dead, are really going to come back to life....

a "zombie" is anyone who did not prepare and/or has decided that YOU have what they need, and They are going to TAKE it, no matter the cost.


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## emilnon (May 8, 2012)

Frost said:


> Umm yea...
> unless... you all think. that the dead, are really going to come back to life....
> 
> a "zombie" is anyone who did not prepare and/or has decided that YOU have what they need, and They are going to TAKE it, no matter the cost.


...well, um... Some people actually do believe real zombies might one day exist... Umm yeah... Didn't know if you are one of "those" people.
(see, I can be a smart ass, too.)


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## Frost (Nov 8, 2012)

emilnon said:


> ...well, um... Some people actually do believe real zombies might one day exist... Umm yeah... Didn't know if you are one of "those" people.
> (see, I can be a smart ass, too.)


Good. I could use the company.


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## oif_ghost_tod (Sep 25, 2012)

Frost said:


> Good. I could use the company.


*stumbles past*

"Brains....garrrrgh"


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## emilnon (May 8, 2012)

Is it true you can use an old metal trashcan as a faraday cage thingie? (I am trying to learn- baby steps!)


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## Claymore5150 (Nov 17, 2011)

Old metal trashcan as the outside, non-conducting (rubber/wood/etc) barrier inside between the electronics and the metal trashcan will work.
Old metal filing cabinets work well, too. Just gotta make sure that the thing you're trying to protect is NOT touching the metal. 

I dunno if I'd worry as much about an EMP strike as much as a coronal mass ejection that triggers something akin to the Carrington Effect (or way worse).
That would be some VERY bad juju.


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## jakerobinson (Nov 15, 2012)

BlueZ,
What are you basing your statement the ECU's won't be effected by EMP whether running or not? I'm not sure I agree but if you have a source to back it up I would be happy to learn about it...


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## Freyadog (Jan 27, 2010)

emilnon said:


> Is it true you can use an old metal trashcan as a faraday cage thingie? (I am trying to learn- baby steps!)


trash can is what we are using as we do not have much that is bigger than that to protect.


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## Freyadog (Jan 27, 2010)

Claymore5150 said:


> Old metal trashcan as the outside, non-conducting (rubber/wood/etc) barrier inside between the electronics and the metal trashcan will work.
> Old metal filing cabinets work well, too. Just gotta make sure that the thing you're trying to protect is NOT touching the metal.
> 
> I dunno if I'd worry as much about an EMP strike as much as a coronal mass ejection that triggers something akin to the Carrington Effect (or way worse).
> That would be some VERY bad juju.


Thumper wrapped all of our electric stuff in those ummmm!! shoot what do you call them, dang, those bags that electronic parts come in. He has saved those things for years. also anything that won't fit in one of the bags he uses bubble wrap to wrap those in and then sits all of this down inside the trash can that has been lined with cardboard.


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## pawpaw (Dec 21, 2011)

Tirediron said:


> A faraday caged alternator should be ok after what ever frys electronics (I do not agree with BlueZ on the non threat of emps) BUT automotive alternators are not very good at returning manual effort, partly because they power their own field ,after being exited like MMM said. a better bet would be a small 12V perminant magnet motor , like a heater blower motor, more out put for the physical effort. and it is going to take a lot of physical effort to recharge a battery from a low state. But it is a good idea.


Is there a one-stop source for info on the output/effort ratio between the alternator & say, a heater fan motor? Not necessarily scientific crap- I know that's a tall order- but even articles or you tube to watch? This subject has always had my attention as I pride myself on my Kenyan improvisational skills.


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## jakerobinson (Nov 15, 2012)

Claymore5150 said:


> Old metal trashcan as the outside, non-conducting (rubber/wood/etc) barrier inside between the electronics and the metal trashcan will work.
> Old metal filing cabinets work well, too. Just gotta make sure that the thing you're trying to protect is NOT touching the metal.
> 
> I dunno if I'd worry as much about an EMP strike as much as a coronal mass ejection that triggers something akin to the Carrington Effect (or way worse).
> That would be some VERY bad juju.


I have heard this put out there on the net that a metal trashcan can serve as a Faraday Cage. When the NBC show "Revolution" was running trailers during the Olympics, I said "Wow, that has to be a High Altitude EMP that caused the power to go off and stay off for 15 years." My buddy and I have researched and studied the impact an EMP would have on the US for several years now.

When I say an EMP, I am talking about a properly delivered EMP at the best location - about 250+ miles above earth approximately above Michigan or Great Lakes area with a powerful enough payload. If we had a nuclear detenation like that we would lose our entire grid, most of Canada's and Mexico's - and, it is very likely the grid would never come back up or if it did it would be distributed. The bigger question is the fact that between 75% and 90% (some say higher) of our population would perish in the first 12 months if power stayed off that long.

My friend is an engineer. He studied the MIL STD 182-125 which is the Military's requirement to harden any electrical device against a HEMP. There are mathmatical equations you can use to deternine how much shielding any *type *of metal and *thickness *of that metal will provide based on it's metalurgy. He figured out that some metals have better shielding characteristics than others... steel, for example, is an excellent conductor but the thickness needed makes it very heavy and bulky and therefore if used as a "personal" Faraday Cage may not be practical. He also figured out that the shape of the cage is important... the less 90% angles and the more rounded corners would make a better sheild. He also figured out that even a hairline crack or gap is the biggest threat to your Faraday Cage. A filing cabinet with the gap between the frame and the drawer would be akin to the size of the Grand Canyon when talking about a Faraday Cage.

In a different forum I was given two links to two companies that actually commericially build EMP-Hardened cages, storage containers, and other devices that could be used to protect gear from a EMP attack. I called one of the companies and spoke to a representative. When I posed the theory of a metal garbage can Faraday Cage he busted out laughing. He did say that "in theory" if you were going to use a garbage can you would need a specialy designed special material Z-type gasket and then there would need to be multiple clamps the create an air-tight compression seal and even then that was a crap shoot.

At that point I invited him to come on our podcast (me and my engineer-friend launched about the show Revolution) as a guest. We decided to start the show so we could use it as a platform to discuss the myths, facts and fiction associated with the TV show but more importantly to spread awareness about the real danger of an EMP. The gentleman directed me to their engineer that also handles all media requests and we have this fellow scheduled to come on as a guest where we will address questions and internet-based theories, suggestion and advice we typically see on forums.

I am not castigating anyone for offereing suggestions about how to protect your gear. It's just that we can use math to quantify definitively (In reference to MIL STD 182-125) what will work and what won't work.

We intend to go for at least an hour with this guy to really squeeze everything we can from a fellow who works with this emp hardening technology. And his company has sophisticated equipment to do testing and to check if their equipment meets these standards...

We have two more podcasts as Revolution, the show, finishes up this season on Nov 26th. Then we will start releasing interviews with interesting folks like Davidson Scott, the engineer in question.

We also have an agreement to interview William Forstchen, the author of "One Second After" - a terrific book about what life and survival in a small town in NC would be like in the even the power goes off and never comes back on...

Hope this helps, if not let's try again.

(Plus, I know I am a newbie here and kinda barged in on this discussion - but I have google alerts set up on EMP Electromagnetic Pulse and I read every article that comes across the net which is great because I discover many prepper, survivor, and homesteading sites I may have never come across)

Cheers,

Jake


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## FrankW (Mar 10, 2012)

jakerobinson said:


> BlueZ,
> What are you basing your statement the ECU's won't be effected by EMP whether running or not? I'm not sure I agree but if you have a source to back it up I would be happy to learn about it...


They <may> be affected by it when running.
But can generally be counted on to not be affected when switched off.

They are semi hardened as they must resist EMI (not as nearly as bad as EMP of course) from the alternator for a _lifetime_.

As for source, one of the authors of the EMPcommission study works in my agency and i discussed this with him a little over a year ago when I was consulting him for a second look at aproblem I was solving.

I also made my living as a civilian and now again as a military, subject matter expert in this general area.
My civilian employer used to rent me out for 300 dollars/hour (I only saw a fraction of that) to solve WMD relateded problems for private, state and federal customers.

Sometimes after the customers in-house "experts" folks failed.

I am not saying this to brag , but in other threads when I tried to replace misconceptions with correct info, I got a lot of push back from those wedded to misconceptions propagated in fiction and other media.

Keep in mind I am trying to correct the Angst w/ regards to vehicles. 
I am not saying this isnt a problem for our grid (though the hard to replace transformers are not easy to blow for an EMP since they are desigend for such huge loads.. it is the computers that control the grid that would be fried and give us very logn black outs..)

Also a good (though lenghty) read for those who want to immerse themsleves in this subject is
http://empcommission.org/docs/empc_exec_rpt.pdf

respectfully, BlueZ


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## jakerobinson (Nov 15, 2012)

Hey thanks for that... 
I was IM'ing the engineer that works at a company that does hardened equip and he also made similar statements... I just wonder if an IC chip in an ECU is hardened to the 80db level the Military says it needs to be. I guess we won't know until it hits ;>)

the bigger problem is geting gas... sure there will be gas to rob (for a while) from cars that are dead but gas stations won't be able to pump and sitting gas goes bad after a while... so even cars that run will eventually become less dependable...

thanks for the link.. i have read most of the report...


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## jsriley5 (Sep 22, 2012)

I did alot of reading on this a month or so ago, there seems to be a huge difference in opinions from one to the next. I read them all. Then decided to hedgem y bets and have spare ignition coils and such for everything I can, I use aluminum foil around a plastic bag with itmes in it, then that in a cardborad box and another layer of aluminum foil, then all those boxes go in a bigger box that gets foiled as well. I am looking ot get some large aluminum boxes and when I build I will use a faraday cage design for the Panic Room to keep stuff in but the aluminum foil acording to most of what I read will work especially in two or more layers. There are better thengs none of which I can afford. So I do the best that I can with what I have. I"m not sure what to think about the super tight sealed containers, one set of reading suggests a less than half inch mesh cage to be adequate. Some say well sealed, and some say parctically air tight metal to metal sealing. Some say to try to ground it some say trying to ground it will just cause you to attract it. And all anyone can agree on is that it is all speculation until a emp happens because we can't properly test it.


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## Marcus (May 13, 2012)

jsriley5,
Your panic room may need to be grounded to reduce any possible heat buildup during an event. Anything smaller than room-sized doesn't need a ground. The wavelength of Gamma Rays are <10^-12 (which are present in the E1 & E2 pulses) will not be stopped by a mesh. You are correct in using nested Faraday cages.
The major thing to remember about a single EMP is that it will arrive in only one vector so certain directions *may* not need shielding *depending on your location.* Even a CME will only come in certain vector bands due to the Earths axial tilt. Unfortunately if you live in the South as I do, protecting against a CME event will require shielding on 3 sides (W,S,E) while a likely EMP event will probably occur on the 4th side (N.)


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## Tirediron (Jul 12, 2010)

BlueZ said:


> They <may> be affected by it when running.
> But can generally be counted on to not be affected when switched off.
> 
> They are semi hardened as they must resist EMI (not as nearly as bad as EMP of course) from the alternator for a _lifetime_.
> ...


And like I told you in all of your other posts many fail or act very poorly from a 25% over voltage from the alternator. the mainpower circuit is hot all of the time and usually runs a 10 amp fuse and is tyed directly to a lot of wire, thus anntenna.


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## pawpaw (Dec 21, 2011)

I have a lot of my smallest electronics (led's,batteries,chargers) in those round popcorn tins we start seeing this time of year. Some of them are huge.
Simply lined them with cork sheeting from the craft store. Rocket science, I know, but my cell phone won't ring from inside any of them, as opposed to the 30 gallon trash can I bought first. Am I operating under misconceptions?
Be easy on me, I'm tender........


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## jsriley5 (Sep 22, 2012)

I'd call it good Paw Paw but would go ahaed and plastic wrap everything then wrap it in alum foil. and if possible box it and wrap it again if you can get it in the can that way. 2 layers are supposed to be good if you get three you should have the aw shucks covered as well. IMO I put stuff that according to most aught to be ok without in foil too can'
t hurt really and better safe than sorry. I"m working on a nested faraday cage for bedside so I can keep my kindle with all my survival booksw and stuff on it and still be able to use it then put in cage when not reading. I can't afford one just for storage. Need to get it all backed up on my puter too.


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## labotomi (Feb 14, 2010)

BlueZ said:


> T
> They are semi hardened as they must resist EMI (not as nearly as bad as EMP of course) from the alternator for a _lifetime_.


An 12 pole alternator (common) turning at 10000 rpm (very high for a car) will produce an AC signal (before rectification) with a period of 0.001 seconds. That's 1 millisecond (1/1000th of a second) and it's a very small electrical field as it's limited to close vicinity of the alternator itself. DC that comes out will produce a magnetic field but one that's relatively constant so it's effect is minimal.

An EMP has a period in the nanosecond range. That's a billionth of a second and the field is much stronger.

The comparisons are so weak that they are virtually useless yet you keep coming back to them.

If you want to make the argument that the car has to endure this over a lifetime consider this comparison. I can throw cotton balls at you for years and not do any harm, but let me throw a single bowling ball at you and see what happens.

Either you were a spokesperson who presented information gathered by others or you're entire persona is false. You haven't made a single "scientific" statement. In fact all your conclusions seem to have been made from a rudimentary understanding of the documents you have linked.


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## Marcus (May 13, 2012)

labotomi said:


> An EMP has a period in the nanosecond range. That's a billionth of a second and the field is much stronger.


That's not exactly correct either.
There are 3 components of an EMP: E1, E2, E3
*E1:* Peaks at ~5 nsec and decays to 1/2 its peak value within 200 nsec.
*E2:* Lasts from 1 msec to ~1 sec and is similar to an EMP produced by lightning.
*E3:* Lasts 10s to 100s of seconds and mainly affects long electrical conductors such as power lines. This is the main danger from a CME-type of event.

The E1 immediately followed by the E2 is the danger to electronics.

To follow up on some earlier posts, a terrorist organization is unlikely to attempt a HEMP attack against the US/ Canada since the required height to achieve a continental effect requires either an ICBM or an IRBM. A HEMP pretty much requires a state actor.

Let's suppose a charter jet flying at 40,000 detonated an EMP nuke. The visual horizon at that height is roughly 264 miles. So the affected area is roughly 219,000 square miles. This represents an area roughly 20% smaller than the state of Texas.

Now let's suppose an EMP nuke is detonated at the top of the Empire State Building (1250 ft.) The visual horizon is 46.7 miles. The affected area is 6842 square miles. This represents an area about 20% bigger than Connecticut.

Remember too that the gamma ray bursts (which causes the E1 & E2 pulses) radiate in all directions, so half of the possible effects are lost. Additionally, the composition of the casing can greatly diminish the production of gamma rays.


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## jsriley5 (Sep 22, 2012)

You know I have thought of that but really a dumb rocket that can reach the atmospheric edge even with the payload as large as a small warhead isn't that hard to make actually just slightly smaller rockets are built by hobbyists and experimenters. 

But even if I have my data screwed up I"d think it would require a state sponsor just to get the nuke so I would think that if they can get a nuke the rocket should be the easy part. launched from a container boat just off the southern coast. NO need for high teck guidance get the desired results from a well built dumb rocket. Are you sure about the e1 and e2 being the primary threat it's been a month but I thought those were the ones that really didn't require much protection from as they were quick but also low powered. Or maybe it was just being unplugged would be adequate to protect from them. And it was the long duration final burst that you needed faraday cages for. I"ll go re read, at any rate I'll stick to my plan that I formulated after a months work of reading everything I could find online.


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## labotomi (Feb 14, 2010)

jsriley5 said:


> You know I have thought of that but really a dumb rocket that can reach the atmospheric edge even with the payload as large as a small warhead isn't that hard to make actually just slightly smaller rockets are built by hobbyists and experimenters.


North Korea has developed nuclear weapons but isn't believed to have miniaturized them enough to put them on a warhead. If they had, they would have boasted about it by now.


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## Marcus (May 13, 2012)

jsriley5 said:


> You know I have thought of that but really a dumb rocket that can reach the atmospheric edge even with the payload as large as a small warhead isn't that hard to make actually just slightly smaller rockets are built by hobbyists and experimenters.


The issue is getting a decent-sized payload to an altitude of roughly 200 miles (the altitude necessary for continent-wide effects.) Getting a hobby rocket up to 100,000 feet (~20 miles) with a small payload requires the largest hobby rocket engines (N? type if I recall correctly.) And even the man portable nukes (suitcase nukes) weighed weighed about 40 or 50 pounds.



jsriley5 said:


> Are you sure about the e1 and e2 being the primary threat it's been a month but I thought those were the ones that really didn't require much protection from as they were quick but also low powered. Or maybe it was just being unplugged would be adequate to protect from them. And it was the long duration final burst that you needed faraday cages for. I"ll go re read, at any rate I'll stick to my plan that I formulated after a months work of reading everything I could find online.


The E2 is the simplest pulse to protect electronics from since it's so similar to EMPs caused by lightning. The problem is that the E1 tends to overvoltage protection systems and it's immediately followed by the E2. 
The E3, due to its lower frequency, affects long conductors like power lines. The E3 will be what destroys the power line transformers. 
The E1 generates something around 50,000 V/m^2 and something around 6 Mw/ m^2. This is why large room-sized Faraday cages need to be grounded. There's a large buildup of heat in a room-sized Faraday cage that isn't grounded.
Protection from the E3 is easy for electronics. If they're not plugged in, they won't be affected by the E3.


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## labotomi (Feb 14, 2010)

Marcus said:


> That's not exactly correct either.
> There are 3 components of an EMP: E1, E2, E3
> *E1:* Peaks at ~5 nsec and decays to 1/2 its peak value within 200 nsec.
> *E2:* Lasts from 1 msec to ~1 sec and is similar to an EMP produced by lightning.
> *E3:* Lasts 10s to 100s of seconds and mainly affects long electrical conductors such as power lines. This is the main danger from a CME-type of event.


The E1 was the portion I was referring to and is the portion that would be potentially damaging to automobile electronics.



Marcus said:


> The E1 immediately followed by the E2 is the danger to electronics.


If the E1 wasn't damaging to electronics the E2 wouldn't be an issue since it's most similar to lightning.

The E1 is indeed damaging to electronics all by itself. The E2 is only a concern because of the damage caused by E1.



Marcus said:


> Now let's suppose an EMP nuke is detonated at the top of the Empire State Building (1250 ft.) The visual horizon is 46.7 miles. The affected area is 6842 square miles. This represents an area about 20% bigger than Connecticut.


The greater density of air at 1250ft would limit the effectiveness of an EMP to far less than the horizon. The gamma rays would interact in a much shorter distance than what would happen in the less dense upper stratosphere where the gamma rays cover a much greater area before collisions occur. Additionally the interaction with the Earths magnetic field is limited. That interaction is what actually causes an EMP.


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## jsriley5 (Sep 22, 2012)

Marcus said:


> The issue is getting a decent-sized payload to an altitude of roughly 200 miles (the altitude necessary for continent-wide effects.) Getting a hobby rocket up to 100,000 feet (~20 miles) with a small payload requires the largest hobby rocket engines (N? type if I recall correctly.) And even the man portable nukes (suitcase nukes) weighed weighed about 40 or 50 pounds.
> 
> The E2 is the simplest pulse to protect electronics from since it's so similar to EMPs caused by lightning. The problem is that the E1 tends to overvoltage protection systems and it's immediately followed by the E2.
> The E3, due to its lower frequency, affects long conductors like power lines. The E3 will be what destroys the power line transformers.
> ...


Well I see I had it a little bassackwards my prep and prevention remians the same but I had the E1 through 3 mixed up in my head.

I think there were Hobbyists building homeade rockets it's been a minute since I was reading it and I really can't remember how heavy the "payloads" were they were launching probably less than 25lbs.

I thought Korea could easily reach the altitude needed just didn't have the range to put it up AND over a potential target. And they were severely lacking in guidance teck to make it very accurate. Anyway Whether it's somthing they have managed to kep a secret (likely) or somthing IRAN has kept a secret (I find that highly likely) or somthing bought from the old Russia when it was in turmoil, or somthing provided by our stalwart friend (heavy sarcasm) China. I personally find it so likely a possibility I am suprised it hasn't happened already. (I flash back to the end of escape from LA  ) Just call me SNAKE


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## Marcus (May 13, 2012)

labotomi said:


> The E1 is indeed damaging to electronics all by itself. The E2 is only a concern because of the damage caused by E1.


That is correct.



labotomi said:


> The greater density of air at 1250ft would limit the effectiveness of an EMP to far less than the horizon. The gamma rays would interact in a much shorter distance than what would happen in the less dense upper stratosphere where the gamma rays cover a much greater area before collisions occur.


You may be correct; I don't know for sure. I will however point out that the higher density of the atmosphere will mean that more electrons are available for the Compton Effect so even a smaller yield weapon may have a greater E1 & E2 than expected.



labotomi said:


> Additionally the interaction with the Earths magnetic field is limited. That interaction is what actually causes an EMP.


That is what causes the E3 part of the pulse as the magnetic field 'snaps back' to its natural state.

The E1 part of the pulse are caused by gamma rays knocking electrons out of atoms in the atmosphere while the E2 part of the pulse is caused by neutrons.

According to the EMP Commission Executive Report of 2004, "In general, it would not be an issue for critical infrastructure systems since they have existing protective measures for defense against occasional lightning strikes. The most significant risk is synergistic, because the E2 component follows a small fraction of a second after the first component's insult {E1 pulse}, which has the ability to impair or destroy many protective and control features. The energy associated with the second component thus may be allowed to pass into and damage systems."


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## Marcus (May 13, 2012)

jsriley5 said:


> I thought Korea could easily reach the altitude needed just didn't have the range to put it up AND over a potential target. And they were severely lacking in guidance teck to make it very accurate.


http://nuclearweaponarchive.org/Usa/Weapons/Allbombs.html

Looking at the data from the above link, it's likely that using a roughly 500Kt warhead will require a payload capacity of ~800 pounds. Putting 800 pounds to an altitude of 200 miles (needed for continent-wide effects) requires a rocket with the payload capacity of a R-7 (which launched the Sputnik) or better. There are only 8 countries/ conglomerates with the capability currently which doesn't include North Korea but does include Israel.

http://en.wikipedia.org/wiki/Comparison_of_orbital_launch_systems
http://en.wikipedia.org/wiki/Comparison_of_solid-fuelled_orbital_launch_systems

The guidance system on such a rocket is somewhat irrelevant since it is an area weapon and only needs to get to the general vicinity before detonation.


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## labotomi (Feb 14, 2010)

Marcus said:


> That is what causes the E3 part of the pulse as the magnetic field 'snaps back' to its natural state.


Yes but with a low detonation height the overall EMP effect is smaller and therefore a smaller E3 component. 


Marcus said:


> You may be correct; I don't know for sure. I will however point out that the higher density of the atmosphere will mean that more electrons are available for the Compton Effect so even a smaller yield weapon may have a greater E1 & E2 than expected.


It wouldn't cause more collisions, it would cause roughly the same number over a shorter distance.

The E1 and E2 would also be smaller. Here's a better explanation than I could put together.


> "Many nuclear detonations have taken place using bombs dropped by aircraft. The B-29 aircraft that delivered the nuclear weapons at Hiroshima and Nagasaki did not lose power due to damage to their electrical or electronic systems. *This is simply because electrons (ejected from the air by gamma rays) are stopped quickly in normal air for bursts below roughly 10 km (about 6 miles), so they do not get a chance to be significantly deflected by the Earth's magnetic field* (the deflection causes the powerful EMP seen in high altitude bursts), thus the limited use of smaller burst altitudes for widespread EMP."


And this concerning a surface blast


> For a surface burst, absorption of gamma rays by air would limit the range of gamma ray deposition to approximately 10 miles, while for a burst in the lower-density air at high altitudes, the range of deposition would be far greater.


And summarizing


> Most nuclear weapons effects vary greatly depending upon the altitude of the detonation. This is especially true of nuclear EMP. The standard reference text on nuclear weapon effects published by the U.S. Department of Defense discusses this relationship extensively in the first two chapters, and provides mutually-exclusive definitions for phrases such as "air burst" and "high-altitude burst." As explained in above sections of this article, nuclear detonations at all altitudes within the Earth's magnetic field will produce an electromagnetic pulse; but the magnitude of the EMP and area that is affected by the EMP are strongly affected by many factors, and is especially strongly dependent upon the altitude of the detonation. (See the discussion above in the "Weapon altitude" and "Weapon distance" sections.) A nuclear explosion in deep space and not in a strong planetary magnetic field would be ineffective at generating EMP.


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## jsriley5 (Sep 22, 2012)

That does kind of assume it would be a one large bomb attack rather than multiple smaller bombs at about the same height as you need that height to get teh results for emp damage even from the smaller warheads but attacks by multiple overlapping smaller bombs would be more effective especially if they are staggered over a period hours or even days providing of course that they think they can manage to lauche the sceond and third waves after tipping their hands with the first. But that just means they need to eliminate or strongly hinder the forces that would be responding to prevent the next waves. NOw don't get me wron I"m not putting forth serious argument at this point but just pointing out some potential gaps in your reasearch and reasoning. YOu are probably correct and since Im too lazy to really go research it seriously on my own I"m just throwing blind arguement out there to feed the fire  . I did in my earlier reading run across some such theory of a "more debilitating" attack such as one staged to hit over a period of days so that we would have pulled our spares out of storage and started fixing things up only to have them whacked again, And all the Civillian aid communications who have went on full alert and have all their gear powered up sending and recieving information will be out and operating and particularly vulnerable to the next wave. And yeah I realize that kind of thing is REALLY pushing it as for a run of the mill Terroristic organization to be able to pull off.


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## Padre (Oct 7, 2011)

> The U.S. EMP Commission tested a number of cars and trucks. Although this was the most comprehensive set of tests on vehicles that has been done, those tests were very poorly done because the Commission was financially responsible for the vehicles, but did not have the funding to pay for any of the vehicles they tested. The vehicles were borrowed from other government agencies, most vehicles from the Department of Defense; and they had to be returned to those lending agencies in good condition.


Can I lay the whole EMP question to rest. BlueZ likes to get on forums and "debunk" the vehicle threat from an EMP. Well I am not buying it, but I am not a scientist and other than determining how it might effect my preps I am not all that interested about the science and I am guessing neither are the rest of you.

So can we agree on this:
1) An EMP very well _MIGHT_ cause a car to stop running, and most likely will case traffic lights to fail which in turn *WOULD* cause massive accidents and traffic jams. 
​1a) IN ANY SHTF these sorts of traffic jams mean that you _MIGHT_ have to bug out on foot, 
​1b)and so whether or not EMP will cause all cars to stop, ALL preppers *SHOULD* have a on foot bug out plan, if they plan to bug out...(which is a whole other can of beans).

2) It most definitely *WILL* cause gas pumps to stop working either by frying the electronics or cutting off the electricity from the grid--meaning that if it doesn't stop cars from working a T+1min it soon will have that effect anyway.

3) No matter whether natural or man made, whether continental or regional in effect, a PREPPER should be preppared for gas shortages, traffic jams, and the possibility of an on foot bug out.

The one scientific question I am left with is equipment that is OFF, be they vehicles or hand held electronics, will they be fried by a HEMP? Meaning how important are Faraday cages?


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## labotomi (Feb 14, 2010)

Padre said:


> The one scientific question I am left with is equipment that is OFF, be they vehicles or hand held electronics, will they be fried by a HEMP? Meaning how important are Faraday cages?


Yes, no and maybe


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## Marcus (May 13, 2012)

Padre said:


> So can we agree on this:
> 1) An EMP very well _MIGHT_ cause a car to stop running, and most likely will case traffic lights to fail which in turn *WOULD* cause massive accidents and traffic jams.


I would change "most likely will case traffic lights to fail" to almost certainly.



Padre said:


> The one scientific question I am left with is equipment that is OFF, be they vehicles or hand held electronics, will they be fried by a HEMP? Meaning how important are Faraday cages?


The handheld electronics will almost certainly be fried if unprotected by the E1 *if they contain transistors or ICs.*
For vehicles, it depends on numerous factors of which most are specific to the event itself. You can mitigate the risk by parking it in a metal building or under a metal carport.

The use of Faraday cages is very important to protect handheld electronics due to the effects of the E1 on semiconductors. The E1 causes the breakdown voltage of semiconductors to be exceeded and ruins the junction itself. The semiconductor cannot be repaired, only replaced.


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## Frost (Nov 8, 2012)

*Andi said:


> fiscal zombie shtf ~ How so ???


there was a pic, a man is walking a wheelbarrow down the street, inside it he has a huge pile of money that is over flowing. A crook robs the man, and takes the wheelbarrow and leaves the money. because it has the least value.

When that $3 gal of gas is $12 and that $2 loaf of bread is $8.
When the money has lost so much worth that the preppers are the only one with renewable food. fuel and supply's. 
The zombies will come. 
THAT is "fiscal zombie shtf"


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## labotomi (Feb 14, 2010)

In reference to a lower altitude EMP being not only being limited in range, but also being less intense.


labotomi said:


> Additionally the interaction with the Earths magnetic field is limited. That interaction is what actually causes an EMP.





Marcus said:


> That is what causes the E3 part of the pulse as the magnetic field 'snaps back' to its natural state.


I'm skeptical of the claim that the blast itself causes the motion of the Earth's magnetic field. Some concepts of magnetism are:

1. they can pass through anything 
2. magnetic lines cannot cross each other
3. magnetic lines follow the path of least reluctance (through iron before air)
4. they try and shorten their path (this is why they exert force)

As I see it, the only thing that can affect the Earths magnetic field is another magnetic field or changing the reluctance of a portion of the atmosphere. The only affect the physical blast has on either of these is the change in temperature of the atmosphere which is very thin at the altitude needed for an EMP.

I believe the E3 component is a result of the E1 and E2 phases and not the physical blast itself.


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## Marcus (May 13, 2012)

Given that the three HEMP waveforms have natural disturbance equivalents, it appears that the E1 and E3 HEMP waveform peak values are likely to be significantly larger in magnitude than the natural exposure levels. This is a concern, because it is known from high-frequency EMC standardized testing that electronic equipment usually requires some protection to survive the ESD and EFT threats. These EMC test levels are, however, much lower than the levels produced by E1 HEMP. For the E3 HEMP, it is clear that power grids can collapse due to the threat of a severe geomagnetic storm, which produces electric fields with similar waveshapes and area coverage; however, the E3 HEMP is again likely to have a much higher peak field level. The protection against severe geomagnetic storms is difficult and has not been fully implemented by any power grid operator at this time. Source:http://www.todaysengineer.org/2007/Sep/HEMP.asp



> I'm skeptical of the claim that the blast itself causes the motion of the Earth's magnetic field.


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. Like a geomagnetic storm, E3 can produce geomagnetically induced currents in long electrical conductors, which can then damage components such as power line transformers. http://en.wikipedia.org/wiki/Electromagnetic_pulse


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## labotomi (Feb 14, 2010)

Marcus said:


> Given that the three HEMP waveforms have natural disturbance equivalents, it appears that the E1 and E3 HEMP waveform peak values are likely to be significantly larger in magnitude than the natural exposure levels. This is a concern, because it is known from high-frequency EMC standardized testing that electronic equipment usually requires some protection to survive the ESD and EFT threats. These EMC test levels are, however, much lower than the levels produced by E1 HEMP. For the E3 HEMP, it is clear that power grids can collapse due to the threat of a severe geomagnetic storm, which produces electric fields with similar waveshapes and area coverage; however, the E3 HEMP is again likely to have a much higher peak field level. The protection against severe geomagnetic storms is difficult and has not been fully implemented by any power grid operator at this time. Source:http://www.todaysengineer.org/2007/Sep/HEMP.asp
> 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. Like a geomagnetic storm, E3 can produce geomagnetically induced currents in long electrical conductors, which can then damage components such as power line transformers. http://en.wikipedia.org/wiki/Electromagnetic_pulse


You're riding the right horse into the wrong stall.

You left out this part of my post which expounds on my statement.



labotomi said:


> I believe the E3 component is a result of the E1 and E2 phases and not the physical blast itself.


I'm not debating that a HEMP will affect the magnetic field of the Earth. I am doubting that it's the actual physical blast that does it. Would a non nuclear blast of the same magnitude have an identical effect on the Earths magnetic field?

If it would then I'm wrong. If it wouldn't, then there's another explanation such as the E1 and E2 components creating moving charged particles which do create their own magnetic field and as such would interact with the Earths.

If you've forgotten, this is in response to a low altitude or surface blast nuke detonation as discussed earlier. It's tangent the HEMP discussion.


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## Norse (Jan 30, 2010)

The results of a EMP or Solar Flare?

Why guess at its potential destruction and just assume it will be terminal, and prepare for the worst scenario, that way you are covered in all degrees.

As far as a Faraday cage, the biggest mistake made is forgetting to GROUND IT.

It is as simple as driving a copper rod into the ground and attaching a heavy gauge copper wire to your cage.

And don't forget to insulate your electrical gear inside from direct contact with the outside of the cage with non conductive material like plastic.

There are many good examples on the net about EMP and Solar Flare protection,,,,,,

http://www.howstuffworks.com/faraday-cage.htm

Unlike the popular thoughts, a Faraday cage does not have to be airtight...... It simply disrupts the pulse and disrupts its wavelength.


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## Tacitus (Dec 30, 2012)

Norse said:


> As far as a Faraday cage, the biggest mistake made is forgetting to GROUND IT.


Why does it have to be grounded?

I see that said every so often, but in the context of an EMP, I don't see why it is necessary.

A Faraday cage is a Faraday cage. The charge will stay on the outside, regardless of whether it is grounded. Even the article you link does not mention the need to ground the Faraday cage. (I "text searched" it for the word "ground.")

The danger in an EMP, as I understand it, is a short term surge in current across the gates of transistors, thereby breaking down the gates of the transistors, and ruining the transistors and any electronics which depend on the transistors (these days, almost any computational or control technology). A transistor is, at the most basic level, a current gate; it allows current to pass when "the gate is open" and blocks current when "the gate is closed." If the gate is destroyed, then the transistor is destroyed, and the phone or engine control which relies on it will not work. Once the EMP passes, things stabilize almost instantly, and there is no threat.

A properly designed, but ungrounded Faraday cage should keep the short term surge at its surface, thereby protecting the electronics stored within it from EMP effects.

Now, I would be happy to be proved wrong, but the need to ground has not been proven to my satisfaction.

(As a side note: Because EMP only threatens transistors, then non-transistor devices, like batteries and flashlights with incandescent bulbs, are not threatened by EMPs. But, devices with transistors, like flashlights _with LEDs_, are threatened by EMP.)

[Edit to add this: I just read an earlier post about needing to ground a room sized Faraday cage because too much heat will build up. My apologies to the poster, but that does not make scientific sense to me. Where does the heat come from? Why does the size of the cage make a difference? While I freely admit I am not an expert on EMP, I do have some technical training in electronics/electricity, and I cannot think of a reason for this to occur. I would be happy to discuss it, though.]



Norse said:


> Unlike the popular thoughts, a Faraday cage does not have to be airtight...... It simply disrupts the pulse and disrupts its wavelength.


Agreed. But I think different wavelengths require different levels of mesh. Until I understand the wavelengths of EMP better, I stick with solid metal.

There was a video posted earlier showing someone remote controlling a helicopter within a wire screen Faraday cage while it was taking massive, Tesla-style "lightning" strikes. The screen cage, while allowing enough air flow to fly, protected the copter from the surges of the strikes, but allowed the RC radio waves to pass so the helicopter could fly. If you can remote control a helicopter through your Faraday cage, I would not be confident it is protected from EMP.


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## helicopter5472 (Feb 25, 2013)

After all this reading I guess I'm stupid, so I will make a cage for transistorized stuff. I guess what I don't understand is say you have a new TV, or DVD player" that's new still in the box" so there is no "surge factor" How will it destroy these? That means all electronics even if they are sitting on a shelf, new, and individual parts like a transistor by itself, will self destruct.


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## Norse (Jan 30, 2010)

Tacitus said:


> Why does it have to be grounded?
> 
> I see that said every so often, but in the context of an EMP, I don't see why it is necessary.


Like I said, it is best to cover all bases. Having a grounded cage defends against other hazards besides EMP. CME or Lightning strikes too can erase hard drives and fry circuitry. A ground adsorbs residual as well as direct current flows.

One of the main enemies of surviving a epic grid failure would be boredom. Some people cannot handle life without being cradled by technology. Storing hard drives and a lap top with thousands of songs, videos and movies might ease stress and prevent getting into trouble with simply too much time on your hands.

And there is also the premise of putting Farday cages with highly sensitive electrical components inside larger cages for double protection!

Of course, having electronics is not of paramount importance in a SHTF situation, but having seemingly endless knowledge based resources and references at lap top and hard drive access, may prove a extremely valuable asset after a grid collapse.

Not to mention power converters and generators would become extremely valuable commodities if the grid failed and was down for years.

Of course grounding your Faraday cage is not absolutely necessary, considering you can do it with a couple of hours work and 20 dollars, Why take the chance?


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## musketjim (Dec 7, 2011)

Arrgh, now I'm really confused. EMP is something I minimally prep for. I can't afford to go buy beater vehicles that are old enough to survive an EMP according to some posts. Just try to train to still be able to travel afterwards and have alternate heat sources. But I'm betting there are electronics that I haven't even thot of that might be damaged by an EMP that would totally take me by surprise. As far as zombies if you kill them by shooting them in the head, couldn't we act preemptively and start shooting people in the head now? Just kidding.


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## Tacitus (Dec 30, 2012)

helicopter5472 said:


> After all this reading I guess I'm stupid, so I will make a cage for transistorized stuff.


I wouldn't trust anything you find on a survival site about the _physics_ of EMP. There are so many sites out there which directly contradict each other. In this limited case, I trust government reports more than some of the survival stuff out there.

I made a cage for my transistor stuff I think I will need after the fact. I have non-LED flashlights for after the fact.



helicopter5472 said:


> I guess what I don't understand is say you have a new TV, or DVD player" that's new still in the box" so there is no "surge factor" How will it destroy these? That means all electronics even if they are sitting on a shelf, new, and individual parts like a transistor by itself, will self destruct.


My understanding (with the caveat that you really can't trust what I say since I told you not to trust what you hear on this limited issue on sites like this, besides which I already told you I am not an expert) is that the wave induces a very short electromagnetic field which produces short lived transient voltages of thousands of volts on exposed electrical conductors (e.g., wires and conductive traces on printed circuit boards), and if those exposed conductors are hooked up to transistors (and they usually are, or why are they there), then they effectively act like an antenna (receiving the EMP) and effectively act like a power line to the transistors, the transient voltage causing a very short but very large burst of power greater than transistor gates can bear. So, yes, even if they are not powered, they are in danger.

Again, just my understanding.


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## helicopter5472 (Feb 25, 2013)

Almost like a jump of static electricity, got it, metal trash cans is on my list.


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## Norse (Jan 30, 2010)

musketjim said:


> Arrgh, now I'm really confused. EMP is something I minimally prep for. I can't afford to go buy beater vehicles that are old enough to survive an EMP according to some posts. Just try to train to still be able to travel afterwards and have alternate heat sources. But I'm betting there are electronics that I haven't even thot of that might be damaged by an EMP that would totally take me by surprise. As far as zombies if you kill them by shooting them in the head, couldn't we act preemptively and start shooting people in the head now? Just kidding.


I would not worry too much about that, because most of the destinations you would travel to with a vehicle will be either clogged roadways with disabled cars.....or simply no reason to go too...grocery stores, gas stations ETC. Unless you live in a rural area, I would never depend or plan on a vehicle for a reliable mode of transportation after a event like that.


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## Tacitus (Dec 30, 2012)

Norse said:


> I would not worry too much about that, because most of the destinations you would travel to with a vehicle will be either clogged roadways with disabled cars.....or simply no reason to go too...grocery stores, gas stations ETC. Unless you live in a rural area, I would never depend or plan on a vehicle for a reliable mode of transportation after a event like that.


I don't think about traveling anywhere...I will bug in, not out.

But think about how you would consolidate your family after the event--nowadays it would be nothing for various members of my family to be 1-2 days walk away from each other--my work commute puts me 17 miles away from home, and my family might be anywhere in a 20-30 mile radius given our normal day-to-day life style. That might be the end of my mother--that would be a tough hike for her.

Also, think about consolidating preps: The EMP is probably the only event where you want all your eggs in one basket...all your preps at one location.

Also, think about water: Without electronics to control the water works, I figure water will stop being pumped into our tower, which means it will stop coming out of the faucet. So, how do you transport water without a car? Water is heavy.


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## jeff47041 (Jan 5, 2013)

Tacitus said:


> I don't think about traveling anywhere...I will bug in, not out.
> 
> But think about how you would consolidate your family after the event--nowadays it would be nothing for various members of my family to be 1-2 days walk away from each other--my work commute puts me 17 miles away from home, and my family might be anywhere in a 20-30 mile radius given our normal day-to-day life style. That might be the end of my mother--that would be a tough hike for her.
> 
> ...


My kids could make the hike to het here, but only if bad guys haven't started their thing yet. Once they are here and safe, I don't have the need for transportation. But, I want my tractor to work as long as possible


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## Caribou (Aug 18, 2012)

Let me see if I can explain the relationship between a faraday cage and grounding. Take your leatherman and a large machete, get in the car and head for the freeway. Get up to 65 and stick your leatherman, with the blade unfolded, out the window and twist it back and forth so that the flat of the blade and the edge are alternately into the wind. There is no big difference in felt resistance. Now do the same thing with the machete. The machete is a room size faraday. Turning the edge into the wind is like grounding it. The leatherman is the trash can faraday cage in this example. Now, about those people in the cars behind you, you know, the ones with all those flashing red lights just explain that you are on the way to your kids school.

As for the cars, my guess that most will be fine. If your car does die or not start then disconnect the battery. Reconnect your battery after a short wait reconnect and try again. This may not reset the computer but then again it might. I expect the metal in the car to provide some protection though not 100%. The windows or radio or who knows what may not work but if it runs be happy.


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## Tacitus (Dec 30, 2012)

Caribou said:


> Let me see if I can explain the relationship between a faraday cage and grounding. Take your leatherman and a large machete, get in the car and head for the freeway. Get up to 65 and stick your leatherman, with the blade unfolded, out the window and twist it back and forth so that the flat of the blade and the edge are alternately into the wind. There is no big difference in felt resistance. Now do the same thing with the machete. The machete is a room size faraday. Turning the edge into the wind is like grounding it. The leatherman is the trash can faraday cage in this example.


I don't think that that momentum exchange from wind to an object is directly analogous to the effect of an electromagnetic pulse field on a large piece of metal. For example, the greater the size of the object, the greater the effect in wind...but I think it would be just the opposite for EMP.

The size of the Faraday cage (the volume encompassed by it) should be irrelevant at the sizes we are talking about. A very small Faraday cage (e.g., one for a single cell phone) is already many, many orders of magnitude larger than the wavelengths of the EMP pulse, and the larger an electrical feature gets, the more immune it is. But it is already immune enough from EMP if we can see it without a microscope...and I don't see how making it bigger would make things better or worse.

On the other hand, transistors are effected because transistors are small. And transistors get smaller every year (Moore's Law), thereby becoming ever more susceptible to EMP.

Maybe if you could tell me _why_ providing a ground line helps, I could be persuaded. Is it to provide a line for current to go to ground? I would think that would make things worse (if there were a problem in the first place, which is what I am doubting). I would think that isolating the Faraday cage (and letting its voltage level float) would be the better strategy. We don't care what the voltage leve of the cage itself is, as long as the voltage level doesn't get to the electronics inside...which it won't if they are insulated sufficiently.

Also, if you are going to ground the cage, do you recommend that the ground line be insulated (e.g., a coaxial cable)? I would think that would be recommended, since you would not want to attach to the cage what might in effect be an EMP antenna (again, assuming a problem in the first place).


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## Caribou (Aug 18, 2012)

Yes, exactly, the ground allows for the discharge. I was trying to depict that with the release of pressure on the knife. The ground should be insulated for certain. Faraday grounding is a science unto itself and if done improperly the ground can act as an antenna and actually make things worse.


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## Caribou (Aug 18, 2012)

Here is a link to an interesting article on EMP's. There are links inside the article about grounding faraday cages.

http://www.futurescience.com/emp/emp-protection.html


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## Tacitus (Dec 30, 2012)

Caribou said:


> Here is a link to an interesting article on EMP's. There are links inside the article about grounding faraday cages.
> 
> http://www.futurescience.com/emp/emp-protection.html


Skimmed it. Word searched it. He spends a lot of words stating what I stated (grounding can cause more problems than it fixes...when done wrong according to him) and explaining how to ground (e.g., shielded, something not often mentioned on survival sites). But he doesn't spend any time explaining _why_ grounding is needed. He just states his conclusions without supporting them. If I missed it, let me know.

He does state that there is no reason to ground small faraday cages (smaller than room size).

He specifically says you need to ground large, room size cages with conductors penetrating them, which basically means a cage with serious holes in it.

I guess since I have no plans to construct a large (room size) faraday cage, much less a cage with holes in it, I won't worry about this.


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## Caribou (Aug 18, 2012)

That's why I don't plan to make a large cage also.


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## LincTex (Apr 1, 2011)

Tacitus said:


> The screen cage, while allowing enough air flow to fly, protected the copter from the surges of the strikes, but allowed the RC radio waves to pass so the helicopter could fly. If you can remote control a helicopter through your Faraday cage, I would not be confident it is protected from EMP.


Well, a lot of the smaller helicopters are now controlled by an IR signal, so no RF signal is needed. Would like to see what kind of helicopter it is.

Are lightning strikes similar to an EMP? Something in the back of my mind tells me no.


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## Tacitus (Dec 30, 2012)

LincTex said:


> Are lightning strikes similar to an EMP? Something in the back of my mind tells me no.


I don't think so. As I understand things (and I have to again say I am no expert), lightning strikes deliver a mass of electrons, but EMPs just create an intense, highly localized, traveling field which disrupts electrons suddenly. Lightning strikes are like releasing a dam into a lake, but EMPs are like dropping a meteorite into a lake. That is probably a poor analogy, but one suddenly adds to the pool of electrons, and the other suddenly moves the electrons that are there in a very sudden and destructive manner...the end effect on the people standing on the beach of the lake (the transistors in electronic devices) could be the same, though.


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## LincTex (Apr 1, 2011)

That makes sense.

In aviation, I see lightning strike damage all the time. No damage going in, but where the lightning bolt leaves it always takes metal with it. Aircraft radios are likely never damaged.... I have NEVER seen any electrical equipment get damaged on an airplane in three decades. 

I'm not saying it can't happen.... but in every airplane I have ever seen with lightning damage, the radios all still worked fine.


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## labotomi (Feb 14, 2010)

Faraday's experiment used a wooden stool to eliminate the potential for grounding. I've never seen an explanation from a reputable source that includes a ground in the diagram or in the explanation. If a ground were needed to accomplish this phenomena it would be included in any explanations related to the theories and principles of operation. Why then, are they conspicuously absent?

I've posted links, diagrams and explanations from sources that utilize the principles of the faraday cage previously. This one probably is the simplest explanation. It explains how it works without going in depth into theories and equations. Again, a ground isn't shown or mentioned.

http://www.magnet.fsu.edu/education/tutorials/tools/faradaycage.html


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## Tacitus (Dec 30, 2012)

LincTex said:


> That makes sense.
> 
> In aviation, I see lightning strike damage all the time. No damage going in, but where the lightning bolt leaves it always takes metal with it. Aircraft radios are likely never damaged.... I have NEVER seen any electrical equipment get damaged on an airplane in three decades.
> 
> I'm not saying it can't happen.... but in every airplane I have ever seen with lightning damage, the radios all still worked fine.


I guess it depends on what the easiest current path is. With a lightning strike, the current (flowing electrons) takes the path of least resistance, which means to or from metal conductors if possible--e.g., the metal shell of the plane or the metal framework of the plane. (I know more about electricity than the structures of planes.) Metal provides the largest pool of easily movable electrons, and may protect "unshielded trasnsistors" by providing an easy path around them. I suppose semiconductors (what transistors are made of) would be next in line after conductors (metal) for a current path.

EMP, however, is not limited to the path of least resistance. It is an electromagnetic wave flowing across all unshielded components, hitting any unshielded transistor.


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## jeff47041 (Jan 5, 2013)

Okay I have a question. I know you guys don't have all the answers, but you know a whole lot more about it than I do.

I've been thinking about making a storm shelter/saferoom in my attached garage. Cut a 10'x10' section of the concrete floor out, dig 2' wide x 8' deep piers. Pour piers and floor as one. Rebar would be sticking up from the piers and floor for the poured walls to tie into.

When I form the walls, I will have rebar going both horizontal for strength, and vertical to tie the cement ceiling to. When I form the walls, floor, and ceiling, if I would also add screening ( I was thinking 1/2" rabbit wire) Would that count as a cage as long as I attach the steel door to the 1/2" wires? Or does the wire need to be exposed on the outside of the concrete?

I thought if I'm building a safe room, I might as well make it a storage for some parts and electronics, as well as some preps.

Any ideas?


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## Tacitus (Dec 30, 2012)

jeff47041 said:


> Okay I have a question. ... When I form the walls, floor, and ceiling, if I would also add screening ( I was thinking 1/2" rabbit wire) Would that count as a cage as long as I attach the steel door to the 1/2" wires? Or does the wire need to be exposed on the outside of the concrete?


First, I can say with a fair amount of confidence that the wire does not have to be exposed on the outside. Encased in concrete is the same thing as exposed as far as a Faraday cage is concerned. The presence of the concrete would not be noticed by the EMP wave; it wouldn't see it at all. Electrically speaking, the concrete would be invisible, and the EMP wave would only see the cage. Make sense?

It counts as a cage if attached to the doors.

Now, whether or not 1/2" rabbit wire is a _sufficient_ cage for EMP...I just don't know the answer to that question. Here is my best guess: I would think that rabbit wire would not be sufficient--it is a cage, but it is a weak cage. I think a cell phone signal could get through, although you might lose a few bars--and it doesn't take much to stop a cell phone. From that perspective, you might weaken the EMP, but maybe not enough. For an overhead/strong EMP, I would rather have continuous aluminum foil more than rabbit wire. (Again, just guessing here; I guess all I can say is what would make me comfortable, and rabbit wire would not make me comfortable.)


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## Marcus (May 13, 2012)

Tacitus said:


> EMP, however, is not limited to the path of least resistance. It is an electromagnetic wave flowing across all unshielded components, hitting any unshielded transistor.


The important thing to realize about an EMP is that it will be a vector, meaning it will have a magnitude and direction. There are certain directions, based on your location at the time of an EMP, that will have higher likelihoods. Thus, someone in say Idaho will want an EMP shield biased to the South and East assuming an EMP is detonated over Kansas while someone in Texas will want the shielding biased to the North.

Again, I will point out that you'll want a solid shield rather than a wire mesh shield due to the wavelength of the EMP. The problem part of an EMP for idle electronics (not plugged in) is generated by cosmic rays which means that the EMP wavelength will be proportional to the wavelength of those cosmic rays. Thus if you protect against the wavelength of cosmic rays, you should be safe. Cosmic rays have a wavelength in picometers which dictates a solid shield.

I will also point out that grounding room-sized or larger EMP cages is done to solely to dissipate the heat generated.

jeff, I'd put your sensitive electronics in nested foil wrapped boxes of your saferoom, preferably on the south wall near the floor, and call it done. You'd be shielded by the earth from anything but an overhead EMP which the nested boxes should be able to handle.


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## Tacitus (Dec 30, 2012)

Marcus said:


> The important thing to realize about an EMP is that it will be a vector, meaning it will have a magnitude and direction. There are certain directions, based on your location at the time of an EMP, that will have higher likelihoods. Thus, someone in say Idaho will want an EMP shield biased to the South and East assuming an EMP is detonated over Kansas while someone in Texas will want the shielding biased to the North.


Depends on whether it is a high-altitude burst. A burst 250 miles over Kansas will affect the atmosphere above Idaho, and the reaction will be a straight downward vector above Idaho (at least, that is what I remember from reading about this years ago). The distance from the burst determines _magnitude_ of the EMP, but not the vector, which would be downward. If it was a low burst nearby then vector is important, as you point out...but you can't predict the direction.



Marcus said:


> Again, I will point out that you'll want a solid shield rather than a wire mesh shield due to the wavelength of the EMP.


I agree with this. I don't know how small the mesh has to be be, but I think it should be very, very small. I would go with solid.



Marcus said:


> I will also point out that grounding room-sized or larger EMP cages is done to dissipate the heat generated.


That I don't believe. I can't think of any reason heat would be generated. The sites I have seen that mention this just assert it to be true, but provide no law of physics which would cause this, and I cannot think of one. If you did want to dissipate heat, then you would need heat sinks all around, not ground wires. Providing an electrical conduction path to ground (as opposed to a thermal conduction path to ground) doesn't make sense either.



Marcus said:


> jeff, I'd put your sensitive electronics in nested foil wrapped boxes of your saferoom....


I agree with this. Rather than building a big room, just make boxes for sensitive equipment.


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## Tacitus (Dec 30, 2012)

Having said all that, let me stress that my knowledge is general physics, electricity and electronics, not EMP. I did some casual reading on the physics behind EMP years ago after reading One Second After, because I enjoy studying physics (no math, though--I left that behind years ago). Since then, I have declined to do further research on the subject of EMP. I am satisfied that it is a legitimate potential future threat. As such, it is in the list of events that I prepare for, although not the sole thing I prepare for. Events I prepare for are weighted by my estimate of the probability that they will occur and the magnitude of likely damage. EMP has high damage, but I think in the short term the probability of occurrence is low...but reasonable preppers can disagree on that. After all, it was recently inadvertently revealed that the DOD thinks North Korea is closer to a deliverable weapon than most thought.


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## Caribou (Aug 18, 2012)

I guess DoD thinking N. Korea is closer to a deliverable weapon explains why they recently deployed 14 additional anti missile systems in Alaska and a like number in California.


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## soticman (Jun 3, 2013)

Do you think an EMP would affect optics such as an Aimpoint or EOTECH sight? I heard that the wiring and electronics are so small they would not be affected.


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## Marcus (May 13, 2012)

Tacitus said:


> Depends on whether it is a high-altitude burst. A burst 250 miles over Kansas will affect the atmosphere above Idaho, and the reaction will be a straight downward vector above Idaho (at least, that is what I remember from reading about this years ago). The distance from the burst determines _magnitude_ of the EMP, but not the vector, which would be downward. If it was a low burst nearby then vector is important, as you point out...but you can't predict the direction.


My mistake. I assumed everyone would know you had to have overhead shielding regardless of your location.

Actually, a vector has both a magnitude and direction, at least in all the engineering courses I took. You are correct that distance affects the magnitude, but the Earth's magnetic field also slightly affects the direction of the Compton electrons generated by the cosmic rays. The Earth's curvature also affects the direction particularly at the edge of the line of sight of the EMP. It is simpler to use line of sight calculators when trying to determine the footprint of an EMP. I recall calculating an EMP pulse generated on a plane at 30,000 ft affects an area roughly the size of Texas.



> That I don't believe. I can't think of any reason heat would be generated. The sites I have seen that mention this just assert it to be true, but provide no law of physics which would cause this, and I cannot think of one. If you did want to dissipate heat, then you would need heat sinks all around, not ground wires. Providing an electrical conduction path to ground (as opposed to a thermal conduction path to ground) doesn't make sense either.


The first thing to understand is that an EMP acting on a Faraday Cage is a *surface effect only.* That means the charge is on the outside of the cage itself. As the electrons bombard the cage, the cage reaches the same potential as the EMP itself (usually given as 50,000 V/m.) Once the EMP is over however, the potential starts to dissipate through the air. This is what causes the heating of the air molecules; the cage wants to return to its normal state. This effect is seen only in room size or larger cages where the build up of the heat is a design consideration.

And you are correct Tacitus, that an EMP is a higher probability event.

soticman, all semiconductor based electronics are affected by an EMP regardless of its size.


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## Tacitus (Dec 30, 2012)

soticman said:


> Do you think an EMP would affect optics such as an Aimpoint or EOTECH sight? I heard that the wiring and electronics are so small they would not be affected.


Marcus is right: they would be affected if they have transistors...and they do have transistors. The smaller the transistors (in other words, the newer the device), the more likely to be affected unless shielded.


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## Tacitus (Dec 30, 2012)

Marcus: Your point on vector, direction and magnitude is well taken. When I said "vector" in my previous post, I meant "direction."



Marcus said:


> Once the EMP is over however, the potential starts to dissipate through the air. This is what causes the heating of the air molecules; the cage wants to return to its normal state. This effect is seen only in room size or larger cages where the build up of the heat is a design consideration


Do you have a source for that?


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## d_saum (Jan 17, 2012)

Caribou said:


> I guess DoD thinking N. Korea is closer to a deliverable weapon explains why they recently deployed 14 additional anti missile systems in Alaska and a like number in California.


Oy! do you have a link for that?


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## Marcus (May 13, 2012)

Tacitus said:


> Do you have a source for that?


Only my experience, common sense, and my BS in Electrical Engineering.

After the EMP event, the cage acts as one plate of a capacitor with the earth being the other plate and air as the transfer medium. Diffusion current is the mechanism by which the heat is generated as the cage seeks a ground state.


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## Tacitus (Dec 30, 2012)

Marcus said:


> Only my experience, common sense, and my BS in Electrical Engineering.
> 
> After the EMP event, the cage acts as one plate of a capacitor with the earth being the other plate and air as the transfer medium. Diffusion current is the mechanism by which the heat is generated as the cage seeks a ground state.


We have similar levels of experience.

Since I don't think it matters whether you ground it or not (and so this argument does not affect my preps at all), and since I'm not inclined to do the very noticeable web research that would be required to respond in detail, I think I will let you have this round.

Until next time, my friend! :beercheer:


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## Tacitus (Dec 30, 2012)

d_saum said:


> Oy! do you have a link for that?


CNN, April 11, 2013: N. Korea may be able to deliver nuke, Pentagon intel says


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## Caribou (Aug 18, 2012)

d_saum said:


> Oy! do you have a link for that?


http://www.news.com.au/world-news/u...laska-california/story-fndir2ev-1226598715301

I got this from an Ixquick search 'anti missile missiles in Alaska'.


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## Marcus (May 13, 2012)

Everything I've read about EMP suggests grounding is only necessary for *larger structures* and would be contraindicated for most applications we'd see on this website. Now if you were going to build a data center or some such, I can see where it would be necessary.

For most applications we'd see on this site, I think nested cages will suffice but you could always bury a room in the ground for some extra protection.

A lot of prepping is common sense. Why invest outlandish amounts of time and money when something simple will work? If you're worried about protecting your vehicles from an EMP, park them under a metal carport or better yet in a metal barn. The major concerns for folks here should be protecting their photovoltaic cells, their ham radios, and their other sensitive electronics which are used every day.


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## d_saum (Jan 17, 2012)

Caribou said:


> http://www.news.com.au/world-news/u...laska-california/story-fndir2ev-1226598715301
> 
> I got this from an Ixquick search 'anti missile missiles in Alaska'.


Ah ok.. this is from March. I was thinking you were referencing something within the last few days. Thanks! :cheers:


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## Tacitus (Dec 30, 2012)

Marcus: We agree more than we disagree on this issue.

d_saum: "EMP Freaker outer"...classic.


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## labotomi (Feb 14, 2010)

Tacitus said:


> Depends on whether it is a high-altitude burst. A burst 250 miles over Kansas will affect the atmosphere above Idaho, and the reaction will be a straight downward vector above Idaho (at least, that is what I remember from reading about this years ago). The distance from the burst determines _magnitude_ of the EMP, but not the vector, which would be downward. If it was a low burst nearby then vector is important, as you point out...but you can't predict the direction.


A characteristic of a high altitude EMP is that the EMP is generated away from the nuclear weapon. Gamma rays emitted by the blast will be released in all directions, but those gamma rays are not the concern. The concern is the electrons released due to those gamma rays due to compton scattering. The electrons released will all travel downward and thus the need for accounting for any vectors other than vertical with respect to the Earth is minimal.



Tacitus said:


> That I don't believe. I can't think of any reason heat would be generated. The sites I have seen that mention this just assert it to be true, but provide no law of physics which would cause this, and I cannot think of one.


The Faraday principle compensates for the electrical portion of the electromagnetic field. The cage protects against the magnetic portion of the field because the moving field generates voltages in the conductive material which causes eddy currents. These currrents produce heat but since the field isn't continuous, these currents and heating are temporary effects. This is the same principle used in induction heating equipment such as bearing heaters as well as the latest and greatest kitchen stove tops. 



Marcus said:


> I recall calculating an EMP pulse generated on a plane at 30,000 ft affects an area roughly the size of Texas.


That height is below what is required to produce an EMP in the sense we're discussing. The effects at that altitude and below are produced by charge separation due to the physical blast and not the gamma ray production and subsequent interactions. The effects below 10km are limited to that of the blast zone and within that area there are more problematic things to worry about.



Marcus said:


> Only my experience, common sense, and my BS in Electrical Engineering.
> 
> After the EMP event, the cage acts as one plate of a capacitor with the earth being the other plate and air as the transfer medium. Diffusion current is the mechanism by which the heat is generated as the cage seeks a ground state.


As I stated earlier, eddy currents are the source of heat generation. I disagree with the capacitor analogy as well. The difference in charge on a capacitor is between the plates and is what you allude to in your statement. In the case of an EMP, the difference in charge is between the outside skin and inside skin of the same conductor that makes the faraday cage. When the source of the charge is removed from the outside of the cage, the inside's equal but opposite charge causes a recombination of electrons and "holes" rendering the cage neutral again.


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## Tacitus (Dec 30, 2012)

labotomi: I think I can agree with everything you wrote.

Just a note regarding attribution: Marcus wrote the "I recall calculating..." text to which you responded, not me.


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## labotomi (Feb 14, 2010)

Tacitus said:


> labotomi: I think I can agree with everything you wrote.
> 
> Just a note regarding attribution: Marcus wrote the "I recall calculating..." text to which you responded, not me.


Thanks. I used the multi quote feature and probably botched it when trying to shorten the comments.

Hopefully my edit corrected this.


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## labotomi (Feb 14, 2010)

Duplicate post


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## Norse (Jan 30, 2010)

Marcus said:


> Everything I've read about EMP suggests grounding is only necessary for *larger structures*


Why take the chance.


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## MetalPrepper (Nov 25, 2012)

Geeze.....I'm sorry gyuz.....but I am reallllllly interested in this topic....and ya'll argue so much on this site.....as usual I have no idea who is right and WHAT we can do to prep for this. I am convinced we will get an EMP in the near future....and I stilll don't know weather to even bother prepping as we live near a nuke plant....and ya'll argue back and forth about that....then if we keep buying all this (expensive) solar stuff.....do we ground it, do we hide it.....what about radios etc, is a metal box lined with cardboard good enough or do we need to ground?...., what to do....I thought this site would help clarify things....but it clarifies canning statagies and dehydrating.....


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## Caribou (Aug 18, 2012)

Norse said:


> Why take the chance.


Because an improper ground can act as an antenna and defeat your small faraday cage. You are probably better off with multiple trash can or smaller size cages than one large room.


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## Norse (Jan 30, 2010)

Caribou said:


> Because an improper ground


It is not rocket science.


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## BillS (May 30, 2011)

MetalPrepper said:


> Geeze.....I'm sorry gyuz.....but I am reallllllly interested in this topic....and ya'll argue so much on this site.....as usual I have no idea who is right and WHAT we can do to prep for this. I am convinced we will get an EMP in the near future....and I stilll don't know weather to even bother prepping as we live near a nuke plant....and ya'll argue back and forth about that....then if we keep buying all this (expensive) solar stuff.....do we ground it, do we hide it.....what about radios etc, is a metal box lined with cardboard good enough or do we need to ground?...., what to do....I thought this site would help clarify things....but it clarifies canning statagies and dehydrating.....


Ultimately, you prep for an EMP a lot like you'd prep for a collapse of the dollar: You need food and water. Guns and ammo. Something to use as a toilet. A way to cook your food and heat your home. If you can protect your vehicles they will probably be seized by the government. Even if you can protect your electronics there won't be electricity for a long time anyway.

There are a number of ways society can collapse. They're different at first but as time goes on they become much more alike.


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## Tacitus (Dec 30, 2012)

MetalPrepper said:


> Geeze.....I'm sorry gyuz.....but I am reallllllly interested in this topic....and ya'll argue so much on this site.....as usual I have no idea who is right and WHAT we can do to prep for this. I am convinced we will get an EMP in the near future....and I stilll don't know weather to even bother prepping as we live near a nuke plant....and ya'll argue back and forth about that....then if we keep buying all this (expensive) solar stuff.....do we ground it, do we hide it.....what about radios etc, is a metal box lined with cardboard good enough or do we need to ground?...., what to do....I thought this site would help clarify things....but it clarifies canning statagies and dehydrating.....


EMP seems to me to be the topic on the Internet with the most disinformation out there...and that is _really_ saying something. You just need to accept that, and evaluate your sources of information (including me) as best you can.

Let me try to simplify by summarizing what we, on this forum, agree upon:

Faraday cages are necessary to protect semiconductors (e.g., anything with transistors or LEDs). Some examples: Radios and LED flashlights need to be in a cage. Old fashioned flashlights and batteries do not. Solar panels should probably be protected, but check what they are made of--I don't know much about them, but I believe the modern ones are semiconductor based.

We agree that grounding is not necessary for smaller than room-sized Faraday cages. So, as long as you are making a small one, like the metal box lined with cardboard that you mention, don't worry about grounding it.

Now, watch someone disagree with the above.


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## Tacitus (Dec 30, 2012)

Norse said:


> It is not rocket science.


No, but someone who doesn't understand antennas might not know to insulate, and if they do know to insulate, they may not know how to insulate (e.g., with a coaxial cable). The people who claim grounding is necessary typically omit how to do it.


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## Tacitus (Dec 30, 2012)

BillS said:


> Ultimately, you prep for an EMP a lot like you'd prep for a collapse of the dollar: You need food and water. Guns and ammo. Something to use as a toilet. A way to cook your food and heat your home. If you can protect your vehicles they will probably be seized by the government. Even if you can protect your electronics there won't be electricity for a long time anyway.
> 
> There are a number of ways society can collapse. They're different at first but as time goes on they become much more alike.


Agreed, but a powerful HEMP (or multiple HEMPs) is by far the worst. Loss of electronics would devastate this society more than any other disaster, apart from maybe a supernova or earth-busting meteor. It wouldn't have as bad an effect on third world nations, but it would destroy the United States. Most Americans would be dead within a year.


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## Caribou (Aug 18, 2012)

MetalPrepper said:


> Geeze.....I'm sorry gyuz.....but I am reallllllly interested in this topic....and ya'll argue so much on this site.....as usual I have no idea who is right and WHAT we can do to prep for this. I am convinced we will get an EMP in the near future....and I stilll don't know weather to even bother prepping as we live near a nuke plant....and ya'll argue back and forth about that....then if we keep buying all this (expensive) solar stuff.....do we ground it, do we hide it.....what about radios etc, is a metal box lined with cardboard good enough or do we need to ground?...., what to do....I thought this site would help clarify things....but it clarifies canning statagies and dehydrating.....


The plant itself will not generate an EMP. If the plant gets shut down by an EMP and if the backup generators are ruined or run out of fuel before it gets restarted then that is a GOOD situation. What I mean is get out of Dodge, do not pass Go and since the banks are probably closed you can forget about the $200. I hope you keep cash on hand and at least a tank full of fuel in spare jerry cans.

As far as protecting your electronics from the EMP I believe we have a general consensus on small faraday cages being effective. There seems to be some difference of opinion as to room size faraday cages. I believe that part of this is because some people, myself included, have not understood fully what others are trying to impart. I will liken building a small faraday to building a kite. You don't need to know a lot you just need to know the process. Starting from the inside you have your electronics, insulation, a layer of metal, if you still are worried add another layer of insulation and another of metal. I will liken a room size faraday to building a plane. You need a whole lot more theory and training. In a couple of paragraphs we are trying to explain an entire book. If you want to build a room size faraday cage read the book.


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## labotomi (Feb 14, 2010)

Norse said:


> It is not rocket science.


Exactly. More people understand rocket science.

The ground isn't needed for the E1 or E2 components and could exacerbate the effects of the E3 component by adding an additional conductor.

Most people who build one of these cages aren't going to locate it outside so any ground cable would probably be at least a dozen feet, possibly much longer. This conductor would cause voltage to be applied to the cage instead of removing it, contrary to the belief and intent of many people.


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## MetalPrepper (Nov 25, 2012)

Caribou said:


> The plant itself will not generate an EMP. If the plant gets shut down by an EMP and if the backup generators are ruined or run out of fuel before it gets restarted then that is a GOOD situation. What I mean is get out of Dodge, do not pass Go and since the banks are probably closed you can forget about the $200. I hope you keep cash on hand and at least a tank full of fuel in spare jerry cans.
> 
> I see you are in Alaska....welll we are not, we are on the east coast in NC....I have no plans to bug out ...ever. The entire east coast has nuke plants and the middle of the country has tornadoes, the west coast has earquakes and fires.....nope, we like it here. So if we get an emp, the nuclear plants will eventually meltdown across the nation.... we will all be affected.


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## Caribou (Aug 18, 2012)

MetalPrepper said:


> Caribou said:
> 
> 
> > The plant itself will not generate an EMP. If the plant gets shut down by an EMP and if the backup generators are ruined or run out of fuel before it gets restarted then that is a GOOD situation. What I mean is get out of Dodge, do not pass Go and since the banks are probably closed you can forget about the $200. I hope you keep cash on hand and at least a tank full of fuel in spare jerry cans.
> ...


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