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Author Topic: What is an Electromagnetic Pulse (EMP)? How does an EMP work? Can it be a bomb?  (Read 15089 times)

Offline neilep

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Dear Arms and the Man experts !

Here is an EMP explosion :



Yes, this is the real deal !!..(well..in the game Quake it is ! ;))

But how does an EMP pulse do what it does ?....and is the effect permanent ?

Would it affect a pacemaker ?


« Last Edit: 25/04/2016 08:22:56 by chris »


 

another_someone

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #1 on: 21/10/2007 21:55:40 »
There is no such thing as an EMP bomb - it is just a nuclear bomb detonated at very high altitude (probably just above the denser layers of the atmosphere).

The idea is that the fast moving particles emitted from the bomb will tear electrons from the atoms, and this would create immense levels of electromagnetic radiation.
 

Offline neilep

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #2 on: 21/10/2007 22:16:57 »
There is no such thing as an EMP bomb - it is just a nuclear bomb detonated at very high altitude (probably just above the denser layers of the atmosphere).

The idea is that the fast moving particles emitted from the bomb will tear electrons from the atoms, and this would create immense levels of electromagnetic radiation.


Thanks George...so there's no such thing (besides a nuclear bomb) that makes EMPulses as a defensive/attacking/disabling tool?

Sheesh !!..all those games I've played have got it oh so wrong !!

Thanks George.

 

Offline techmind

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #3 on: 21/10/2007 23:54:47 »
Dear Arms and the Man experts !

Here is an EMP explosion :

But how does an EMP pulse do what it does ?....and is the effect permanent ?

Would it affect a pacemaker ?


I suppose the closest (non-nuclear) thing to an EMP bomb would be a lightning strike. This can wreck delicate electronics within maybe 10 metres of the strike... The high electric field can induce a voltage (exceeding the insulation breakdown voltage) in semiconductors (chips/transistors) can blow them. The brief current surge and thus magnetic "pulse" can induce a high current in parallel conductors which may also do some damage. But anyhow, all confined to a pretty short-range damage zone considering the biggest spark known to man!

If you fuse a wire or cause breakdown then the damage will be permanent... but you could expect "soft" damage eg computer crash/hang (works after reboot) over a wider area. I guess there's also an inbetween condition where the EM pulse causes an otherwise "soft" latchup but which in turn causes an abnormally high current to flow from the devices' own power supply and burn-out a component that way.
« Last Edit: 22/10/2007 00:00:29 by techmind »
 

Offline techmind

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #4 on: 22/10/2007 00:07:36 »
Thanks George...so there's no such thing (besides a nuclear bomb) that makes EMPulses as a defensive/attacking/disabling tool?

Well, a sufficiently high power radio-transmitter can cause equipment to go on the blink. At microwave frequencies you'd be able to focus the energy onto a point target fairly effectively. A few kilowatts of microwaves focussed onto a few square metres would probably prove quite destructive - but it'd be targetted rather than cause widespread damage.

Have you tried putting an (unwanted) CD in a microwave oven? (You should also put half a mug of water in there to prevent damage to the oven, and leave it on for no more than 15 seconds). Try in the dark for best effect.
 

lyner

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #5 on: 22/10/2007 11:14:01 »
The most intense electromagnetic fields are produced with lasers (light) but the  effect was achieved, originally, at microwave frequencies (masers). They are, usually, hideously inefficient, requiring vast amounts of   electrical energy input . This makes them pretty useless as battlefield weapons. The 'chemical laser'  has been developed which is, relatively, much more portable. The energy has all been stored in the manufacture of two chemicals. These are carried (in an enormous US bomber)  and pumped through a laser, where they react and produce a coherent, high power beam of light. You point the beam with a system of mirrors.
I guess the same could be done at microwave frequencies to jam / overload comms equipment.
Only a modest field strength can upset sensitive equipment but doesn't do permanent damage - unless it's your heart pacemaker!
 

another_someone

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #6 on: 22/10/2007 14:02:55 »
The most intense electromagnetic fields are produced with lasers (light) but the  effect was achieved, originally, at microwave frequencies (masers). They are, usually, hideously inefficient, requiring vast amounts of   electrical energy input . This makes them pretty useless as battlefield weapons. The 'chemical laser'  has been developed which is, relatively, much more portable. The energy has all been stored in the manufacture of two chemicals. These are carried (in an enormous US bomber)  and pumped through a laser, where they react and produce a coherent, high power beam of light. You point the beam with a system of mirrors.
I guess the same could be done at microwave frequencies to jam / overload comms equipment.
Only a modest field strength can upset sensitive equipment but doesn't do permanent damage - unless it's your heart pacemaker!

I think the distinction here is between power and energy.  There devices can produce a lot of localised energy, but there peak power output is far less than an EMP (even at a small target area), which is why they are unlikely to permanently destroy the equipment through electrical overload (but also, why they can do more damage through straight forward heat transfer than the electrical overloading).
 

lyner

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #7 on: 22/10/2007 15:12:20 »
I agree. But you can't carry a nuclear device around with you and use it at will. There will be more subtle methods of providing enough energy , at the right frequency, to do something like the required damage.
Wiki discusses alternative, non-nuclear ways of producing EMP. The huge advantage of this would be the localised nature of the damage - rather than taking out some of your own equipment and all of civilian  communications at the same time.
http://en.wikipedia.org/wiki/Electromagnetic_pulse
 

Offline Nobody's Confidant

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #8 on: 22/10/2007 17:57:55 »
Quake was an average game, but Quake 4 was wicked amazing.
 

Offline techmind

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #9 on: 25/10/2007 15:36:52 »
But how does an EMP pulse do what it does ?....and is the effect permanent ?
If you really want to get some idea as to what's going on in military and weapons research, trot off to http://www.defenceiq.com - they run conferences on the subject. Warning this is not bedtime reading.

I told them to stop contacting me after they started sending me invites to "Sensor to Shooter" and "Directed Energy Weapons" conferences. Talks with headings like "Precision Targeting - Compressing the Kill-Chain". Not my cup of tea.

Look up "High Power Electromagnetic Radiators" HPEM, "Intentional Electromagnetic Interference" (IEMI), "High Power Microwave" HPM.
« Last Edit: 25/10/2007 15:38:48 by techmind »
 

Offline i am bored

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #10 on: 04/11/2007 22:19:20 »
Quake was an average game, but Quake 4 was wicked amazing.
i agree with ben quake 4 was amazing but quake wasnt too shabby
 

Offline nikomaster

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #11 on: 05/11/2007 02:01:54 »
An EMP is an small part from a nuclear bomb.

An EMP is powerful pulse capable to stop the function of an Electronic Based Device,that magnetic shockwave flows throught a direction changing all devices to that direction, CMOS devices are most affected, however a simple resistive circuit can take this magnetic explotion.
 

Offline McQueen

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #12 on: 07/11/2007 00:05:14 »
Quote
Reply with quote
There is no such thing as an EMP bomb - it is just a nuclear bomb detonated at very high altitude (probably just above the denser layers of the atmosphere).
Quote
An EMP is powerful pulse capable to stop the function of an Electronic Based Device,that magnetic shockwave flows throught a direction changing all devices to that direction, CMOS devices are most affected, however a simple resistive circuit can take this magnetic explotion.
What about the HAARP project somewhere near Alaska, I thought they were experimenting with huge amounts of voltage to create an EMP? I saw something about it on Discovery, can't remember the details though.
« Last Edit: 07/11/2007 00:14:21 by McQueen »
 

Offline mrxavia

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #13 on: 30/11/2007 08:53:21 »
There is no such thing as an EMP bomb - it is just a nuclear bomb detonated at very high altitude (probably just above the denser layers of the atmosphere).

The idea is that the fast moving particles emitted from the bomb will tear electrons from the atoms, and this would create immense levels of electromagnetic radiation.

Unfortunately there is such a thing as an EMP bomb other than a high altitude detonated nuke...
A nuke isn't the only way to produce a pulse of em energy.
 

Offline Soul Surfer

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #14 on: 30/11/2007 09:43:22 »
In order to simulate a nulear EMP and test equipment that was shielded against it devices had to be designed to create the sorts of fields and risetimes that could be expected.  These can be weaponised for particular local requirements but they can never have the vast area effect of the nuclear device exploded at the edge of space.

The effect of EMP is not on human beings (although I did know a hard line defence scientist who wanted to find out if he could kill someone with his big EMP machine) but on electronics.  It produces voltages and currents in unprotected equipment that destroy the integrated circuits.  So it kills almost any normal electronics in a very large area.  The best way to protect someting is to put it in a sealed metal box but that's a bit difficult if you're building a radar or some communications equipment, but it can be done with careful design and a lot of military equipment is protected in this way.  It is one of the reasons why real military equipment is so expensive. 
 

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Electromagnetic Pulse Bombs !!..How do they work ?
« Reply #14 on: 30/11/2007 09:43:22 »

 

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