Electromagnetic Pulse Device

[pyroglycerine]

Hi,

 

Do EMP devices exist that can disable/power off all electronic devices within a given radius? Eg. Such as the one contrived in Prison Break season 3 episode 5.

I was once told by a Russian friend of mine that when he was in school, his friend had made such a device to power off people's mobile phones with a range of about 5m.

How do they work? Are they used in police/military operations?

 

Thanks,

 

pyroglycerine

[davidivad]

you would have better luck with microwaves.

 

don't cook yourself.

[Schneibster]

As davidivad hints, there are hints about the construction of such devices most of which involve magnetrons and ultracapacitors and vaporize their wires. You can find a lot of sites of varying credibility that talk about them. I've never stepped up and done the math and engineering to prove it, but my sense of the magnitudes involved says your friend is not being outrageous at 5 meters distance, but I'd be surprised if it would actually smoke the circuits as opposed to just temporarily interdict communications. A true EMP will burn transistor junctions. That takes a lot of power. I mean a lot. The first EMPs were made with kiloton (i.e. terajoule) nuclear weapons. You really don't want a terajoule being suddenly released anywhere in your near neighborhood even if you have a blockhouse. And you sure as heck aren't doing it with a magnetron the size of your fist.

 

I've seen articles that claimed a thousand pounds of ultracapacitors and a magnetron the size of a watermelon and worked over a distance of hundreds of meters/yards, no more. It seems like a good way to smoke all the electronics in an enemy tank; needs work to be feasible in aircraft. Interesting as an anti-missile close-in weapons system, fry the electronics before the missile can get close enough to hurt you. Need some serious cybernetics work though before it would be practical. Also you'd need to have shielded systems yourself to fire it off; it's just not that easy to make a thing like that all that directional. The backlash could smoke your fly-by-wire computer. After which you become aerodynamically unstable. At Mach 2. Bad idea. Think fly on freeway waiting for the windshield.

 

I've seen articles that talked about purpose-designed EMP nuclear weapons, blown off in the ionosphere to maximize the pulse and spread it over a continent. Megaton-range devices are discussed IIRC.

 

Megawatt radar arrays on guided missile cruisers of the great powers are said to be able to smoke the electronics on aircraft that fly through the beam too close; this is at the edge of believable with systems fifteen years old, and eminently possible these days as the synthetic aperture phased arrays have crept up into the tens of megawatts.

 

Which kind are you talking about? Or are you talking about another technology?

Edited April 8, 2014 by Schneibster

[davidivad]

i was going to bring up the fact that nuclear warheads were emps too.

i was basing my assertion of microwaves on the fact that police use directed microwave beams to interrupt car electronics systems and thus disable them for a stop.

this is probably still in the testing phase right now.

but it does make sense. you can melt metal in a microwave and you can interfere with radios.

it is a continuous directed EMP.

[Schneibster]

In modern cars they can blow confuse the mixture computer, which fails safe and turns off the gas. (I don't think they're going to use something that will blow peoples' computers on the far side of the freeway.)

Edited April 8, 2014 by Schneibster

[pyroglycerine]

i was going to bring up the fact that nuclear warheads were emps too.

i was basing my assertion of microwaves on the fact that police use directed microwave beams to interrupt car electronics systems and thus disable them for a stop.

this is probably still in the testing phase right now.

but it does make sense. you can melt metal in a microwave and you can interfere with radios.

it is a continuous directed EMP.

 

As davidivad hints, there are hints about the construction of such devices most of which involve magnetrons and ultracapacitors and vaporize their wires. You can find a lot of sites of varying credibility that talk about them. I've never stepped up and done the math and engineering to prove it, but my sense of the magnitudes involved says your friend is not being outrageous at 5 meters distance, but I'd be surprised if it would actually smoke the circuits as opposed to just temporarily interdict communications. A true EMP will burn transistor junctions. That takes a lot of power. I mean a lot. The first EMPs were made with kiloton (i.e. terajoule) nuclear weapons. You really don't want a terajoule being suddenly released anywhere in your near neighborhood even if you have a blockhouse. And you sure as heck aren't doing it with a magnetron the size of your fist.

 

I've seen articles that claimed a thousand pounds of ultracapacitors and a magnetron the size of a watermelon and worked over a distance of hundreds of meters/yards, no more. It seems like a good way to smoke all the electronics in an enemy tank; needs work to be feasible in aircraft. Interesting as an anti-missile close-in weapons system, fry the electronics before the missile can get close enough to hurt you. Need some serious cybernetics work though before it would be practical. Also you'd need to have shielded systems yourself to fire it off; it's just not that easy to make a thing like that all that directional. The backlash could smoke your fly-by-wire computer. After which you become aerodynamically unstable. At Mach 2. Bad idea. Think fly on freeway waiting for the windshield.

 

I've seen articles that talked about purpose-designed EMP nuclear weapons, blown off in the ionosphere to maximize the pulse and spread it over a continent. Megaton-range devices are discussed IIRC.

 

Megawatt radar arrays on guided missile cruisers of the great powers are said to be able to smoke the electronics on aircraft that fly through the beam too close; this is at the edge of believable with systems fifteen years old, and eminently possible these days as the synthetic aperture phased arrays have crept up into the tens of megawatts.

 

 

Answered my question, thanks

[Schneibster]

Sure.

[Enthalpy]

Nuclear weapons were only the first attempt to create EMP. Presently, they use pulse electric power, are operational and in use in most armed forces, and most military electronic equipment is designed to resist it.

 

A common design is a flux compressor, were chemical explosive compresses a strong magnetic flux to increase quickly the induction. Invented by Sakharov hence old, used against Al Jezeerah's station in Iraq during the war. These are bomb-sized.

 

A more recent design uses quick electronic switches. Probably MOS transistors, simply, but they could be Blumlein or even a Marx generator. They fit in a suitcase, destroy to 10-100m range, temporarily disable to 100-1000m range.

 

Such an EMP weapon was probably used in Aosta, from the effects observed by inhabitants.

 

So it's absolutely actual.

 

I wish to ask airliner designers to build their electronics EMP-resistent.