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Are you shielded?

Posted: Tue Nov 22, 2005 3:47 pm
by woodchip
Reading about how the US is extremely vulnerable to a emp attack. So I got to wondering about how one might shield their fav. game rig from electro-magnetic pulses when some cam...er terrorists launches a nuke with a cheap scud missle they bought from NK. I mean heck, what would we do if a nuke blast wiped out our computors? Any suggestion on how to shield a computor?

Posted: Tue Nov 22, 2005 4:17 pm
by REDDER
My gaming PC is totally encased in a shell of Lead 3 feet thick.

It is also buried 5 miles underground directly below my house.

Overheating has always been an issue as well as upgrading the video card.

Posted: Tue Nov 22, 2005 4:20 pm
by Krom
REDDER wrote:My gaming PC is totally encased in a shell of Lead 3 feet thick.

It is also buried 5 miles underground directly below my house.

Overheating has always been an issue as well as upgrading the video card.
:lol:

That's about what it would take. Of course if you are close enough to a bomb to recieve an EMP strong enough to fry your computer, data loss will be the least of your problems. :P

Posted: Tue Nov 22, 2005 4:36 pm
by REDDER
Krom is also correct... besides if your PC was shielded what about your monitor and laser mouse? They will be disabled as well.

Posted: Tue Nov 22, 2005 6:06 pm
by Xamindar
I just had an interesting thought...Is it possable to create an EMP? Like with household items or things that can be bought? hehe :P

Posted: Tue Nov 22, 2005 6:10 pm
by Mr. Perfect
The derpatment of homeland security sugests that you combat EMP by purchasing large rolls of aluminum foil and duct tape.

BTW, do Faraday cages absorb EMP as well as radio waves? I supoose they don't, seeing how no one has suggeseted them...

Posted: Tue Nov 22, 2005 6:17 pm
by REDDER
I remember seeing a TV show on the topic of an EMP type device that can be pointed at a vehicle to disable it.

I believe the Police or Feds are working on one. I also remember it using microwaves or something.

Posted: Tue Nov 22, 2005 6:22 pm
by REDDER

Posted: Tue Nov 22, 2005 7:24 pm
by Ferno
lol. scud. those things couldn't hit anything within 100 miles, let alone on the other side of the world.

that'll be like trying to hit a gnat at 500 yards with a softball. :P

Posted: Tue Nov 22, 2005 8:20 pm
by Duper
A nuke blast doesn't have to be close to knock stuff out. A number of yeasr ago, Hawaii blacked out due to an EMP from a test to the south quite aways away.

Posted: Tue Nov 22, 2005 8:45 pm
by Capm
actually, its scary just how easy it is to build a crude emp bomb.

Posted: Tue Nov 22, 2005 9:01 pm
by woodchip
REDDER wrote:I remember seeing a TV show on the topic of an EMP type device that can be pointed at a vehicle to disable it.

I believe the Police or Feds are working on one. I also remember it using microwaves or something.
Before you pooh pooh this, I'll tell you a few things.
My father told me that when he was a kid some guy invented a device that when pointed at a vehicle, it would cause the motor to die. Made the local papers (this was in WI so Sarge if you read this you can try looking it up) but the curious thing was the military came in, hushed everything up and took the guy and put him to work. This was back maybe in the 30's. Fast forward to Vietnam. When the B52's flew over head, a buddy of mine was telling me how the generators would go dead and wouldn't restart until the bombers had flew past. Both my dad and my buddy was dead serious when they told me these things.
So think what you want.

Posted: Tue Nov 22, 2005 9:09 pm
by roid
shouldn't a faraday cage shield against an EMP?

i remember at a science park kinda place (Scitech) in Perth, in a special theatre room they had a few high voltage experiments setup that they would activate at various times throughout the day for small audiences.

one was a Van de Graaff generator somewhat like this:
Image

Another was what must have been a "Telsa Coil", it was a much higher wattage thingy that needed to charge for a few hours before every performance. They would turn off the lights for effect and when they flicked the switch it would arc out in very thick, loud, ~3 meter arcs to the faraday cage that surrounded it - like a huge eye in the storm. Lasted for about 10-20seconds before it had to be recharged.

looked like this
Image

Without the faraday cage the guy said that it would have fried every HAM radio within a few kilometers.

edit: but from what i'm now reading - and the pictures i'm seeing of outdoor tesla coils - i doubt they will do any damage.

Posted: Tue Nov 22, 2005 9:20 pm
by Genghis
Read more Schneier.

Posted: Tue Nov 22, 2005 9:21 pm
by fliptw
depends on what the cage is made of.

The entire point of a faraday cage is to conduct EM thru it to the ground - basically a hollow conductor.

The conductor would basically need to stand up to the force of a potential EMP that might be more current than volts.

Posted: Tue Nov 22, 2005 9:45 pm
by roid
http://en.wikipedia.org/wiki/Faraday_cage
http://en.wikipedia.org/wiki/TEMPEST
"Some United States national security buildings are contained in Faraday cages, intended to act as a TEMPEST shield, and possibly also as a mitigation against electromagnetic pulse"

Posted: Tue Nov 22, 2005 11:48 pm
by MD-2389
REDDER wrote:I remember seeing a TV show on the topic of an EMP type device that can be pointed at a vehicle to disable it.

I believe the Police or Feds are working on one. I also remember it using microwaves or something.
Ahh, the good ol' "Microwave Gun". All I've heard are people making cracks about using them to disable patrol cars behind them, but never actually seen one. I bet not too many of you will see one given the legality of such devices. Especially now.
Capm wrote:actually, its scary just how easy it is to build a crude emp bomb.
No, what's scary is how easy it would be to build a crude neutron bomb. It wouldn't be pretty.

Posted: Wed Nov 23, 2005 10:09 am
by REDDER
I want to clarify that I only possess a mid-range knowledge of electronics at best.

Upon observing the idea of a faraday cage I can see it working for lightning strikes, static discharges, etc.

Isn't a PC Case a faraday cage in a basic sense of the word? The same goes for a steel supported building? Especially if they are properly grounded.

I think that an EMP Pulse will pass through these faraday cage and still disable or disturb the electrical circuit.

Posted: Wed Nov 23, 2005 1:44 pm
by MD-2389
Your case is NOT a faraday cage. It would have to be entirely enclosed in metal to be a true "cage". Most cases have a plastic front cover, which is a huge gaping hole. Then theres the intake and exhaust fan vents. It would really depend on where the blast came from whether or not your case would block anything. Even so, it would have to be a rather weak blast in order for your case to "shield" your system.

At any rate, like Krom said, if you're within range to be affected by EMP, you've got bigger things to worry about. ;)

Posted: Wed Nov 23, 2005 7:47 pm
by fliptw
and there are cheaper and easier ways to screw over a computer than an EMP.

Like water. With sugar in it.

Posted: Wed Nov 23, 2005 11:45 pm
by Ned
Bend over and kiss it goodbye

or more likely: heard a loud boom and be stunned and be gone split second later.

Just like when the D3 single player game when the train hits you in the Seoul Korea Metro tunnel

BTW, why are you worrying abour EMP when apparently even flooding is too complex for 'us' to handle :x :roll:

Posted: Thu Nov 24, 2005 12:46 pm
by Mobius
Correct me if I'm wrong, but isn't EMP a temporary thing? Gear settles down after a while?

Posted: Thu Nov 24, 2005 3:21 pm
by fliptw
Mobius wrote:Correct me if I'm wrong, but isn't EMP a temporary thing? Gear settles down after a while?
Thats like saying lighting tickles when it strikes.

Re: Are you shielded?

Posted: Thu Nov 24, 2005 4:11 pm
by Sarge
woodchip wrote:Reading about how the US is extremely vulnerable to a emp attack....
According to who? (whom?) Why is the US more vulnerable than other countries? Come on, 'Inquiring Minds' want to know! ;) Spill the beans Woodie, what do you know that we don't?

Me thinx you think too much. Stop spending so much time on the pot reading 'comix', it's affecting your judgement.

Zing! Bam! Boom! Weeeeeeeeeee!

:P

Posted: Thu Nov 24, 2005 9:06 pm
by MD-2389
Mobius wrote:Correct me if I'm wrong, but isn't EMP a temporary thing? Gear settles down after a while?
Buy a clue Mobius! :roll:

A dog taking a #2 on the carpet is a temporary thing too, but it still leaves a mess. :roll:

Re: Are you shielded?

Posted: Fri Nov 25, 2005 6:45 am
by woodchip
Sarge wrote:
woodchip wrote:Reading about how the US is extremely vulnerable to a emp attack....
According to who? (whom?) Why is the US more vulnerable than other countries? Come on, 'Inquiring Minds' want to know! ;) Spill the beans Woodie, what do you know that we don't?

Me thinx you think too much. Stop spending so much time on the pot reading 'comix', it's affecting your judgement.

Zing! Bam! Boom! Weeeeeeeeeee!

:P
Alas poor Sarge, he doth doubt too much. Would Janes be sufficient as a source? Remind yourself not to play poker with me. :wink:

http://www.janes.com/defence/news/jdw/j ... _1_n.shtml

Posted: Fri Nov 25, 2005 11:10 am
by MD-2389
Interesting read. I don't suppose you have the whole article handy?

Posted: Fri Nov 25, 2005 12:22 pm
by woodchip
No. I wish I could afford to pay for a subscription so I could read all their articles in full.

Posted: Fri Nov 25, 2005 5:55 pm
by Duper
fliptw wrote:
Mobius wrote:Correct me if I'm wrong, but isn't EMP a temporary thing? Gear settles down after a while?
Thats like saying lighting tickles when it strikes.
Actually, some EMPs are temporary. There are a number of determining factors. EMPs from a "close" nuke blast (assuming it wasn't close enough to turn you into ashes) generally are not temporary. Again, it would depend on the type of radiation.

Posted: Fri Nov 25, 2005 6:25 pm
by fyrephlie
EMP = great old plot point for movies and tv

EMP =\= something im more than mildly concerned about, specially whether EMP hits and i lose all my internet bookmarks and have to find them again...

yawn @ threat level teal: something somewhere might happen somehow

Posted: Fri Nov 25, 2005 6:36 pm
by Duper
An EMP is what kills florecent lighting when lightening strikes. A mild one, but an emp none the less.

Posted: Fri Nov 25, 2005 6:42 pm
by fyrephlie
my buddy was an EMP in Dungeons and Dragons

Posted: Fri Nov 25, 2005 7:52 pm
by MD-2389
Duper wrote:An EMP is what kills florecent lighting when lightening strikes. A mild one, but an emp none the less.
I don't know if you've seen this episode or not, but in an ep of Mythbusters they built a "house rig" to basically test two myths at once. The one where you shouldn't talk on a corded telephone during a thunderstorm, and you shouldn't take a shower during a thunderstorm. They took this rig to a special building where they do similar testing. They had the generator running at 300kV, or up in that range anyways, I forgot the exact number, but it was really up there. The strike on the "house" had enough EMP to fry the digital VOM and throw out the focus on the cameras they were using in the entire room!

Posted: Sat Nov 26, 2005 4:34 pm
by Duper
weird.. I've never heard those before. I've been told you should unplug all your appliances and such, but that's in case of a direct strike on the house; not an emp.

Do I bother doing that? pfft! no.

btw, what was the finding on mythbusters?

Posted: Sat Nov 26, 2005 11:06 pm
by MD-2389
Oh, those were plausable/confirmed. :P They had to remove the ground to get the telephone to zap the ballistics gel dummy though. :D

Posted: Sun Nov 27, 2005 6:36 pm
by Canuck
I live in the Rocky Mountains, fairly high up, and when we get lightning, it is literally being generated all around you and the strikes are spectacular. I used to repair electronics and I've seen a Sanyo fax machine blow 3 layers of lightning protection, they had a fusibile resistive links, supression diodes, movs, and finally 2 gas tubes... all blown.

Usually the gas tubes don't blow but the elements inside were totally vapourized on the inside of the glass, such that the tube acully was a dead short across the pins. Some fuses do this. The Movs were vapourized, just bits of charcol.

When I was ordering the tubes the parts guy at Sanyo scoffed and said these things never go wrong. They do if the flashover voltage far exceeds the ratings... 14 KV in the case of these tubes.

Posted: Sun Nov 27, 2005 6:45 pm
by Duper
Whoa...>o.0<

Posted: Mon Nov 28, 2005 8:05 am
by woodchip
I saw a phone literally explode off the wall just after a lightening strike. A buddy of mine had just hung it up like 30 seconds prior.