A Faraday cage does not need to be grounded. It's not the same thing as a lightening rod.

It depends on the wavelength of the signal. Cell phones use very short wavelengths so their signal can penetrate through small holes.

People here are saying that a military EMP would have much longer wavelengths that would be blocked. I don't know if that's true. Also, I'd be wary about extrapolating experience gained from EMPs that were mere side-effects of a nuke, to EMPs that were specifically designed as weapons in the own right. There may be ways to put the energy into short wavelengths to cause maximum electronic damage.

Ahhh, some of that long-ago reading on EMP is coming back. Yes, you're absolutely correct. I forget what they were called, but there are EMP-specific weapons tuned to much higher frequencies, like into the microwave region, if I recall correctly.

They're called High-power microwave (HPM) and are one of several directed energy weapon technologies, none mature as far as I know.

It's hard to respond without sounding confrontational. Believe me, I don't want to appear that way so please try to understand. My goal with this document is to factualize alot of the information. Though I realize my intial portrayal was less than ideal (having reread it out sounds very chest-thumpy ish so I may reword it shortly). I just want to make a thread with 'the facts' about emp in it. So if you can point me to the evidence, I'll post it. It's that simple.

Here's an interesting video to show how the frame of a car gives electricity a better path to follow than through the driver:

http://gizmodo.com/gadgets/cars/lightning-strikes-car-with-man-in-it-243268.php

Make sure you watch it all the way to the end. Note the car starting and all electronics functioning.

Does this mean that an EMP will have the same thing, absolutely not. I'm simply illustrating a point in regards to the frame of the car operating in a designated fashion.

When starfish occurred, you only hear about wide scale effects. You hear about issues with items hooked to phone lines (burgular alarms), radio towers, street lamps, etc. You don't hear about personal radios/electronics or vehicles being affected. Mostly they had some minor interference but that was all. There are two possible explainations I can think of for this:

1) The relative lack of sophistication of the electronic components involve resulted in an inadvertent resistance to EMP.

2) That smaller electronics with antenna less than 30 inches didn't concentrate enough energy to receive significant damage.

So anyways, I'm still evolving this document. Sorry if I came off sounding like a know it all

I would say your research and mine are in conflict becuase we are looking for different scenarios. You are looking at it as a problem with very tight and fine parameters that can be defeated with finess. I approach it as a problem with much wider parameters that is going to attack using brute force of a degree that would make the old Red Army look... subtle.

While what you are talking about is accurate for certain weapons that are designed to generate EMP as thier main action (although I do question the <30" and antenna and fuel injector survival), a phenomena (man made or natural) that produces an EMP as a side effect frequently is creating a spike of noise on all frequencies. So I don't worry about a given frequency, or it's harmonics, I hit stuff close to what you are set up to filter and try to spike it that way. And yes, most phenomena have a range of frequencies they like, but if you are only worried about one risk factor you end up being unprotected against others. (And I know about that- I've killed components that way on the bench in a couple of signals classes.)

These phenomena are also much more powerful those created by a dedicated EMP generator. EMP generating weapons are designed to reduce the effective range, so as not to endanger your own forces and to minimize collateral damage. But if I want to wipe out everything in a country, the most cost effective way is a high altitude detonation of a multimegaton device. If I believe they are shielded for aspike of X amplitude based on their public reports of being sheilded for .5X, I choose a yield that will give me 1.5X amplitude. And it will be a lot less expensive than clean EMP generator. Nukes are cheap, the alternatives obnoxiously expensive in comparison.

If I pump enough power into a circuit fast enough, it is dead. If I can spike it faster than the protective components can burn out or throw, or just hit it with enough current to get the pulse to arc through those gaps, then the circuit is gone. And heck, even if it doesn't die, if the surge heats with wiring to the point that solder joins fail or insulation melts and things short out, the circuit has failed.

Objective accomplished. I like the analogy of the bullet proof vests when talking about EMP- yes, it stops some bullets, but not all bullets, and unless I hit your trauma plate, I can stab you through one. If you pulse it right (say, tuned to the length of your average mouse cable or the distance between high tension towers if want to hit electrical and communications landlines), or just brute force it, the shielding is done.

And I'm not trying to be arguementative. I might be sounding cranky, but I don't mean it- it's been the week of morons at work *crosses eyes*- please tell me your customers have a better clue than mine do. My questions about the information stem from it being, as I said, a bit at odds with everything I've ever learned from people who were engineers for NASA and the DOD back when we didn't think that electronics were the wizards wand that will solve all our problems.

If I had to take a guess as to why the components you mentioned weren't effected, either (a) it wasn't reported (huh, the radio's dead, I'll buy a new one) because people don't add it up and (b) a long antenna picks up a lot more signal than a short one, so the pulse on something plugged into the grid is going to be worse.

No, my customers are not more intelligent. I work for a high speed internet tech support company as a 'data coach'.

Not to derail my own thread but it's hard to top having someone argue with you that guam is part of the *continental* united states and that california was on another continent (along with being another country). The guy really believed it too. I can tell you stories that would make your brain bleed.

Anyways, like I said I'm not an engineer. I agree with your logic; I just would prefer to have it in some referenceable format. My goal with this document is contentual accuracy. If that means that everything is pretty well SOL, cool. I Just need to make sure that we have something I can point to with it.

Incidentally, I've already learned a few things, so it's working as intended

Simple rule of thumb- x might break it, 10X will really break it.

It's the old debate of armour vs warhead. You'll never be able to make shielding that can't be overloaded by making a bigger warhead. And the bigger bang is always more cost efficent. :P

I'm afraid the high point of my customer service this week was replying to "you people wrote the ******* program" was "well, you bought it two years ago and haven't had a problem before Vista."

Yeah, the boss didn't like that one.