I personally hate iPods so I dont mind if they all go up in a EMP.
But as to the cost and ease of making one. A small scale device could be made for about $3000 then chucked on a back of a truck and parked and detonated.
It doesnt need the pinpoint accuracy and other features your military has built into theres to be effective. There are simple designs that could be used and they may not be the best design but it doesnt mean it wont be effective.
Buying the parts would attract very little attention because nobody would be looking out for most of the components.

I think you are underestimating how easily this could be done with the right design.

Another thought:

If any useful electronic device survives an EMP it will be worth 20 times it's weight in gold. Do you really want to have to protect your iPOD from murderous theives? Think "Waterworld" where dirt is priceless.

Not trying to go TEOTWAWKI, but you should consider what effect protecting/taking things with you will have. You do NOT want to stick out like a sore thumb after any event that effects ALOT of people.

Well, there are some problems with the physics of your statements. First, an EMP from a nuclear detonation is likely to generate ac fields in the EHF range. One component in the shunting ability of a faraday screen is wavelength, and the mesh size of a faraday screen determines the effective cutoff frequency efficiency of it's shunt. In short, unless your screen mesh size is approaching microscopic, it won't do much to protect against a nuke based emp.

Second, as the field intensity increases, the shunt capabilities of a faraday screen diminish because the ambient ground level goes up. Unless your ground plane is deep and is connected to the screen using massive conductors, the screen will develop a potential, or series of potentials that will induce fields in the equipment within. There are very few real true earth faraday screens in existence, at least ones capable of shunting major emp hits such as we are considering. Most faraday screens I know of are used to protect against lightning hit level emp. These can be big, but are localized and not nearly the magntiude a strategic emp attack would generate.

Third, cars are not grounded to earth, and therefore float on an insulating layer (four tires). They are not able to shunt an emf field at all, and provide virtually no protection to electronic gear contained within. To find a vehicle that would still run after an emp surge, it would have to have a generator instead of an alternator, because the diodes and the regulator in the alternator are semi-conductors and would be blown by an emp. You might get lucky and the battery would not take a hit, and the coil might not blow open, but anything silicon based is going to go after a few hundred electron volts. All those new LED lights everyone is toting these days will suddenly quit, leaving the good ole incandenscents. I dunno if the xenon and halogen lights will take the voltage or not, but my guess is certainly the new plasma based lights and the fluorescents are suspect.

Perhaps one of the smartest things I've ever heard about emp threat was to use tube technology and keep whatever appliance you were planning on using disassembled like a kit and packed away in an airtight aluminum container. If an emp hit, likely the componentry would survive intact, you could reassemble the unit, and assuming alignmnet was not a problem put it into operation. There are more than a couple dedicated ham operators and a few government agencies that subscribe to this practice.

The botom line is consumer electronics are going to toast in an emp field. Only the truly dedicated technicians who planned ahead have any chance of operating electrical gear after the fact, and even then, they're going to have to come up with suitable electrical generating devices (you can pretty much say goodbye to all those new portable generators too, which are dynamically controlled with solid state electronics).

Just enclosing equipment in a metal structure will not keep it safe. I've witnessed a lightning strike take out a telco switch station from 1/4 mile away. This was a site that was in a metal building, with a good grounding system, and plenty of circuit protection. If it can happen to a $50k switch site, then it can happen just about anywhere.

> and as soon as you attach your headphones, the faraday cage doesn't mean diddly

That's why I said get 2 iPods. You listen to the one that isn't in the biscuit tin.

Bank records should be protected by the bank. It really shouldn't be that hard for them to store a backup in a Faraday cage.

It's true there would be bigger problems than iPods. Then again, there is a strong psychological component to survival and if music is what you think will get you through the disaster, I say go for it.

All that sounds a bit "worst case". An EMP will surely be subject to inverse square laws, so there will be a wide area, away from ground zero, where a little protection will be better than none at all.

HEY! Finally a situation where being poor is a benefit! All of your (non-electronic) stuff fits into the back seat and trunk of your 1964 VW bug and the road ahead is CLEAR! <img src="/images/graemlins/smile.gif" alt="" />

Sue

EMP works by induction in conductors. Microwaves work by stimulating molecules. If you put your hand in a microwave for 8 seconds it will be severely damaged, not true with EMP. I would be interested in any references you have for your claims.

Does anyone have any idea the range of a non-military EMP device? Are we getting worked up over nothing? If a "really big" home grown device is able to produce a pulse only 10 miles wide then we are getting all fired up over nothing.

Yep, and as Brangdon points out, inverse square laws apply. I'd figure the best non-nuke emp might make it to the horizon if popped at ground level, maybe 12 miles if they really pump the local field up and aren't in close proximity to any big conductors (including underground). The gauss level is what we would measure I reckon just to get a good basis. Figure it'd have to be about 100 times more voltage than your standard lightning bolt, so we're probably looking at a 10 to the 7th or 8th power voltage level with a high spiking square wave type leading edge. That'd generate enough harmonics to beat the slew rate on most solid state junctions within that range.

In contrast, it isn't all about the amount of voltage, but the type. Like I was saying before, when you get the frequency component up to ionizing levels, it can compound the effects. Propogational loss is diminished in this case (the inverse square law doesn't work quite the same, but still is a factor). Popping a nuke at 40 miles up with a 10 to the 11th or 12th order (we're talking a really good hydrogen bomb thermo-nuclear detonation, probably 15 megaton or larger) voltage level would probably effect at least a 200 mile radius on the ground, likely a whole lot more if the pulse finds it's way into the grid and surges down the line a lot further. The more x-ray and gamma ray generation, the more effective it will be at slamming all those transistors into oblivion (greater penetration of obstructions).

BTW, humans aren't immune to the emp. I believe that at 5,000 rem the central nervous system blows, and our switch gets abruptly flipped off. I can't remember what the conversion is from eV to rem, but it is not a small number.

Really? Wow, I had no idea. Do you have any scientific references? I would really like to learn a bit about this. Has anyone ever died solely because of EMP?