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Chris
07-13-2012, 09:50 AM
Sorry if this is a repeat thread.

Found this while trolling the internet

http://boards.straightdope.com/sdmb/showthread.php?t=615732

Anyone read this thread? How valid are the points?

Chris

raketenjagdpanzer
07-13-2012, 10:00 AM
Sorry if this is a repeat thread.

Found this while trolling the internet

http://boards.straightdope.com/sdmb/showthread.php?t=615732

Anyone read this thread? How valid are the points?

Chris

In essence they're all valid points. No, you can't protect something just by unplugging it or turning it off. If you have a big metal box (like, say, a Dutch cookie tin) and put a wooden block in it, then put a laptop, radio, etc. on the block and can close the lid without the device you're trying to protect touching the sides, you've created a Faraday cage that's basically EMP-proof. Likewise if you built yourself an all-metal shed with no large openings, or openings that could be closed with metal shutters, and put items inside that were, like the cookie tin, equally kept off the metal surfaces inside and you make sure to run a grounding cable off to a metal stake in the ground, presto, you've got an EMP-resistant storage unit. It's going to help some but it's not going to be perfect.

Remember, though, to heighten the disaster aspect the T2k designers indicated that "EMP was far worse than anyone expected" (a throwaway line I ignore, but that's just my campaign).

Legbreaker
07-13-2012, 10:05 AM
To my understanding, the people appear to be quite knowledgeable on the subject.
Many people try to call a car body a default faraday cage, but without grounding it's going to do jack. Also to my understanding, faraday cages are generally "tuned" to the frequency range most likely to be expected - if the gaps between the metal of the cage are too great, it's not going to do much good.

Targan
07-13-2012, 08:36 PM
Also to my understanding, faraday cages are generally "tuned" to the frequency range most likely to be expected - if the gaps between the metal of the cage are too great, it's not going to do much good.

Correct. It's literally a case of any openings being smaller than the physical length of any wavelengths involved. EM radiation to most people (myself included) seems like an almost magical process, so it seems strange that something as simple as what I've described above is how it works. But to my understanding, that's the case.

DocSavage45B10
07-14-2012, 08:45 AM
The finer the mesh the better, down to metal boxes, like say tanks. Another thing to remember is that EMP damage is probabilistic in nature, ie a roll of the dice.

bobcat
07-22-2012, 12:00 PM
the ISO container bunkers being sold by several vedors currently will work.(or just about anything underground in my area) also will provide limited protection against EMP but again the best thing to do is shut down you devces unplug any wires connected to them put them in a faraday cage and pray for the best. i know a guy who's real paranoid and has his entire hunting cabin lined with steel plate thats grounded with steel mesh in the doors and windows connected to the plate, so on. granted with the localised EMI in this area that is a smart thing to do to protect ones electronics.

pmulcahy11b
07-22-2012, 07:18 PM
I will not go into any potentially-classified information, but even in the Cold War, most military vehicles, aircraft, and electronics are much more hardened to EMP than most people think. However, while it might protect the components of the vehicle or its electronics, that doesn't mean the crew will have the same level of protection. (The radio's working, but no one's answering...the lights are on, but no one's home...)

Legbreaker
07-23-2012, 02:07 AM
...the lights are on, but no one's home...

That's situation normal for most armoured crewmen though... :D

Panther Al
07-23-2012, 02:16 AM
Now now... just because you PBI lot think you are ten foot tall and bullet proof, doesn't mean you always wind up calling for Armour support before the day is done.


Oh, my bad, its the 82nd that thinks they are ten foot tall, the rest of you lot are more realistic.


At any rate, on point, EMP protection has gone by the wayside by and large. A while back I related a conversation I had with some contractors installing equipment in our tanks, and the short of it is, newer stuff is by and large commercial grade equipment given thicker boxes and green paint: as they said "We don't worry about it any more, we figure the vehicle will shield it so we can save money by not building it in."

Legbreaker
07-23-2012, 02:20 AM
And it's not like EMP is a serious threat in the current world situation. Unlikely anyone who has nukes will be using them any time soon....

Tegyrius
07-23-2012, 06:15 AM
And it's not like EMP is a serious threat in the current world situation. Unlikely anyone who has nukes will be using them any time soon....

Yeah, but Pakistan is three bad fatwas away from turning into an all-you-can-grab arms bazaar at any given time.

- C.

Webstral
07-23-2012, 11:55 AM
Yeah, but Pakistan is three bad fatwas away from turning into an all-you-can-grab arms bazaar at any given time.

- C.

Won't that be fun? If I were in my twenties, I could be gainfully occupied as a rifleman or another specialist needed in LIC and MIC for an entire career. Alas, I'm married with children. My opportunity to be a bloodthirsty killer in multiple countries appears to have gone the way of my dreams of being a lunar colonist.