[george (OP)]

I heard a rumour the other day that classified weapons that affect electrical systems, disrupting computers etc, but don't hurt people, are being used in Iraq.

How do they work ?

George.

[chris]

George

Briefly, e-bombs unleash a pulse of electromagnetic radiation that induces a surge of electricity within electrical devices, damaging them.

Here's a recent link from discovery about the technology :
http://dsc.discovery.com/news/briefs/20030324/iraqweapon.html

[Corbeille]

Just outsource your IT department, that'll bugger them up!

you can't crack me I'm a rubber duck!

[OmnipotentOne]

Yessssss the bomb generates massive fluctuating magnetic current that would fry electrical devices past repair. A big enough surge could burn out semiconductor devices, melt wiring, fry batteries and even explode transformers. I think they first reported this when the hydrogen bomb was being tested over the pacific ocean,the weird thing about this was that street lights were blowing out 100 miles away in Hawaii.
Something about the Compton effect?  Meah thats my 2cents.

To see a world in a grain of sand.

[qpan]

Would a faraday cage not stop an e-bomb? Not too sure - seems like it should be though. And they're cheap to build too- all you need is a box made from wire mesh.

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe

[tweener]

qpan, it would depend on the cage.  The EM pulse that we're talking about here has an extremely wide bandwidth (it is a very short pulse) and thus some radiation will get through the mesh of a Faraday cage.  To really stop all the radiation, you need a solid walled room that is well grounded thick enough and properly connected around the corners etc.  They can be quite expensive to build.  One place I used to work had a chamber like that to calibrate very sensitive instrumentation.

----
John - The Eternal Pessimist.

[Corbeille]

"E - Bombs".  Is that what people from Yorkshire shouted during air raids?

you can't crack me I'm a rubber duck!

[chris]

E-by-Bomb surely ?

Chris

"I never forget a face, but in your case I'll make an exception"
 - Groucho Marx

[Corbeille]

Originally posted by chris

E-by-Bomb surely ?

Chris

No Chris, that would be Lancashire. Don't they teach regional stereotypes at your university?[]

you can't crack me I'm a rubber duck!

[Ylide]

Incidentally, the US has been using weapons like this since Vietnam.  The bigger bombers carried them to take out pursuing jets or guided missiles.  The Russians actually built analog backup components using vacuum tubes in their MIG fighters so that they wouldn't crash and burn if hit with an EMP weapon.  

The things you learn listening to your friend's dad who was a cold-war era military pilot.  



This message brought to you by The Council of People Who Are Sick of Seeing More People

[gsmollin]

The non-lethal unconventional weapons include EMP weapons, which function as described above, a similar weapon that uses microwaves (EMP weapons peak in the VHF region), and weapons that discharge a cloud of graphite fibers over power plants and high voltage lines to short them out to the ground.

That last one is my personal favorite, since I contemplated its design over 40 years ago. I was a kid at the time, and had found a spool of fine wire. Being also interested in model rocketry, I designed a model rocket that would unspool the fine wire and carry it over a (~200,000 V) high voltage line. Fortunately, I never had the nerve to try it. But I have wondered about the guy who dreamed up that graphite weapon. I think we would understand each other.

[tweener]

I've actually tried shorting power lines with wires.  I've never gotten one to ground, but it's quite spectacular when you get a wire spanning two of the legs of a three-phase line. It does not bring down the power grid though.  If the wire doesn't vaporize fast enough (which it does), the circuit breakers will interrupt the flow for a short time and then turn it on again after the slag from the wire has blown away.  []

----
John - The Eternal Pessimist.

[OmnipotentOne]

this sounds like something I would have done last year in my hell raiseing phase!  but I've never heard of it before, by merely putting wire over a power line would short it out?  that doesent sound right.

To see a world in a grain of sand.

[tweener]

The wires you see in power lines do not have any insulation on them.  Between any one wire and the ground there will be anywhere from several thousand to several hundred thousand volts potential, with LOTS of power to back it up and make a REAL BIG current flow.  If it's a three phase line (which all of the big ones are), then the voltage potential between any two of the wires will be double what it is to ground.  

Putting a wire across the power line so that it touches any two lines (or even comes close) will "short" the lines.  However, my point is that it would have to be a REALLY big wire to hold up long enough to actually cut the power.  For small wires, they heat up so much and so fast that they basically just vaporize in a large (and loud!) flash of light.  The ciruit breakers on the power line may cut out because of this, but are usually designed to cut back in automatically after about a second.  This is to minimize the effects of tree limbs (and small wires) that accidently cause a very short duration overcurrent situation.  

I live on a farm and you can always tell when the power is going to be out for a while when it goes off and on three times and then quits.  This is when the power company has to send someone out to see what happened and reset the breakers.

----
John - The Eternal Pessimist.

[gsmollin]

The graphite bomb blows lots of fibers, and its aimed at a power plant, not a transmission line. In a power plant there are a set of high tension transformers that raise the generator voltage (~12,000 V) to the transmission voltage (~278,000 V in a modern design). This switchyard is susceptible to the graphite bomb.

[PhirePhly]

The F-111E had a module on it's tail that would generate an EMP without a "bomb" - I don't know what was in there, but there was a rumor that it was tested in Seattle (at the Boeing plant) and it shut down the electrical grid for an afternoon.



Thanks,
 
L. Lisov

[simeonie]

Do all of you go to university or something? I am only 14 meh..

mmm hi!

[Ray hinton]

I DONT GO TO UNIVERSITY,THEY CANT FIND ONE THAT WILL TAKE ME, THIS IS WHAT HAPPENS WHEN YOU MESS WITH ELECTRICITY,    

RE-HAB IS FOR QUITTERS.