[Methos]

I just got through reading the book "one second after" by William R. Forstchen. Its about the events following an EMP event - power failure, food shortage, looting, breakdown of civil order. Very interesting reading.

If you are unfamiliar with what an EMP is and what it can do, basically, it fries computer chips causing failure of the component whether its controlling the computer and ignition in your truck, a nuclear power plant's controller systems, or radios, tvs,...etc. They are produced by nuclear detonations. Wikipedia has a very good article on the subject.

The sun can also produce this same effect as an emp that can fry solid state electronic components as well. These events are called coronal mass ejections. They are rated on an intensity scale by nasa. The earth's magnetic field can shield from most of them, but it is possible that an extraordinarily intense one can overcome this and cause major problems. We just had a big one a few weeks ago that was right in the center of the scale, which is a rather large one compared to normal sun activity. It was such a cause for concern that they wrote an news blurb about it; but as it turned out, the earth took care of it fine.

IMHO this is probably the most realistic event that could actually cause the sort of SHTF scenario we see in the movies. It would place us back into the 19th century overnight; as well as cause the demise of millions and millions of humans in a 1st world country like ours. The scary thing is that one of these massive ejections could have happened at any time before the advent of solid state electronic components (maybe around 1970) and we'd have never known it happened because it wouldn't have had any observable effect on anything biological. Today we have the SOHO, which is a set of two satellites that monitor the sun's activity 24/7 and can detect and measure the intensity of these CME's. When one occurs, we have about 4 days notice before the wave gets to earth. Just enough time to go to town and get some provisions and gas, and kiss your air conditioning goodbye -- IF they announce it to the public, that is.

The only protection I've read about that can protect your personal electronic equipment is to create a faraday cage around the items. A metal trash can is what I use for my radios and gps unit. Just FYI.

 

[jakeg823]

I know little about the subject myself, buuuuut if it affects the earth, wouldn't it likely take out satellites as well? Making your gps a high dollar paperweight?

 

[dnr1128]

I know little about the subject myself, buuuuut if it affects the earth, wouldn't it likely take out satellites as well? Making your gps a high dollar paperweight?

Your GPS, your car, your computer, your phone, pretty much anything that has electronic/electrical components.

Essentially, a CME/EMP is this: a VERY high power radio wave that anything metal picks up and gets fried. The only protection is a Faraday cage, which is a metal shield that diverts the wave to ground, protecting whatever is inside it.

We've all heard about the tin foil hat, right? The concept comes from the faraday cage. Aluminum and copper are good conductors, and as such are good for making a cage, providing that you can ground them.

WND had an article about it not long ago. http://www.wnd.com/?pageId=190721

 

[jakeg823]

Yeah I'm vaguely familiar with the concept...but I'm just wondering if there is even a point in protecting your gps when odds are the satellite will get fried....and even if it does still work after just a few hours use you'll need to recharge the battery....and unless you carry a generator on your back with a adapter for the car charger, then your gps is still useless. I'm just trying to figure the concept out is all

 

[dnr1128]

Basic electrical circuits should be ok, but I'm not an electrical engineer or electrician. I just know some basic electrical principles that I use to troubleshoot on the job. Older vehicles, like my '95 chevy truck, would probably be ok (if it is turned off when the emp/cme hits), since afaik when you turn off the ignition you're actually opening the circuit. The metal body should catch the blast and divert it away from the ignition system. Newer vehicles have an "always on" system (as I understand it) similar to a computer that turns itself off and on. Maybe somebody else could pitch in on that point.

Stuff you would want to protect would be basic communications equipment, like small portable radio (if it has HF/shortwave it would be great since a CME would only affect the side of the globe pointed towards the sun, the other side would be shadowed and be ok, so you could get info from other nations), maybe handheld radios if you're a ham. If you have a small generator I would ground it while you have it in storage. You could easily get the stuff you'd need at any hardware store. If it is pullstart it would probably be ok, especially if you have it grounded. If it is electrical start I'm not sure. Might work if you disconnected the battery. Don't know about that. Google it.

Plans for a faraday cage are easy to find online. You could make one very easily and cheaply to cover a small building like a shed or something, just by getting aluminum screen, covering the building and grounding it.

I haven't yet done this, but very very soon I'm gonna build a storage shed (my carport is getting crowded with junk) and I'm gonna get prices and so forth on shielding the building to protect stuff inside.

 

[dnr1128]

This is a video about EMPs. They make reference to the blackout of the northeast in 2003. I remember that well, as I was still living up north. Things were nuts. 'Course, we all were in Katrina, and know how it was. Think of that going on for a year or more.

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Here is part 2, where he sets off a small EMP

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[sidroski]

How would you know when it was safe to bring your devices out of a faraday cage? Talking on the lines of hand held radios and things you would need keep in touch with other members of your area and such if you went out to check your land?

 

[dnr1128]

In the event of a CME, depending on the extent of the flare, it could last a little while. The benefit of that scenario is that usually there is some warning. However... In the event of an EMP detonation, there is very little if any warning, but once it detonates, it's over. Most likely, it's over before you know what happened. As shown in the video above, nothing visible or physical would happen (aside from the slight chance of a fire caused by sparks, but thats unlikely). Once it happens, it's over.

In 1859, there was a solar flare that hit the earth that was so powerful that it caused sparks to fly from the telegraph keys. At that time that was the only extensive wiring systems in society, so the effect on the nation was small, relatively speaking. If the same thing happened now, we'd be instantly put back to the 19th century because of our dependence on technology.

 

[Methos]

How would you know when it was safe to bring your devices out of a faraday cage? Talking on the lines of hand held radios and things you would need keep in touch with other members of your area and such if you went out to check your land?

I would not remove my equipment from protection until I found out if it was an EMP or a CME. If a CME it will be over pretty much as fast as it started with no after effects, so you can fire up radios for info right afterwards. If its a EMP then there is the possibility of a secondary strike that could happen at any time after the first. Its an unknown and only a guess but after a week or so, I'd think the enemy would have probably fired his secondaries by then, and even then, those secondary strikes may be warheads intended for ground targets, causing a localized emp effect, and not intended to cause emp over a vast area like a high altitude detonation. The affected area is related to detonation altitude and bomb yield.

As far as satellites, I'm not sure on the military ones. (gps) They are likely "hardened" from emp. Don't know for sure. If I made and launched any sat, commercial or military, I'd build it within a f-cage due to the chance of various radiations including CME's.

I'm also not sure if a faraday cage has to be grounded. I've always been under the impression that earth grounding is not necessary - but it probably couldn't hurt. Military vehicles of all sorts are likely hardened, but are not earth grounded.

 

[Methos]

Ok, I pulled my can out, removed the stuff, and took some pics. This is my poor man's faraday cage. All the wood was scrap, can came from lowes, and the inside liner is a walmart camper's mat. About 30.00 of stuff. I can store all my handheld radios, hf radio, 3 cb's, tuner, 2 shortwave radios, gps unit, NV scope, portable hard drives, thumb drives, and a spare laptop in this device and still have room for another shelf layer for more stuff on top. The large ammo cans can be done like this too by removing the rubber seal but this will hold so much more. :tophat:

 

[dnr1128]

Test it by putting your cell inside it, put the lid on it, then call your phone. If it connects, then the cage isn't working. Try it both ungrounded and grounded.

 

[sidroski]

Good points. I think I will put things up like scanners, eotechs and other stuff I don't use every day.
2 Questions - is that trash can grounded?
Does my steel safe serve the same purpose? Do I need to ground it or is it a poor choice even grounded?

 

[Methos]

sidroski, the can is not grounded. Don't know about the safes. I would think that since the hinges and crossbolts are a metal to metal attachment of the door to the body that it would serve the purpose just as well.

I did put the cell in the can and peeked in at the signal level. It went down to one bar or no bars but never went down to the level where it said "no service". Have not had anyone call the phone while in the can yet though. I'm also not totally sure that a 800-900mhz range radio signal is comparable to an em pulse since the pulse is more like a 360 degree wave of electric voltage that goes out. Their intensity is measured in kilovolts per meter. The burst radius is dependent on altitude and the effect on your equipment is related to your distance from ground zero.

Here is another interesting article on emp tactical bombs that covers a lot of stuff.

http://www.abovetopsecret.com/forum/thread59555/pg1

In it, it says that the most effective method is to wholly contain the equipment in an electrically conductive enclosure, termed a Faraday cage, which prevents the electromagnetic field from gaining access to the protected equipment.