Hey! My electronics knowledge is pretty basic (I'm more of a programmer), but I've found myself quite interested in the subject of malicious EMP devices. I'd like to find out more about the subject - anything about how they work or to make variations of such devices is useful to me.
Specifically what I'd like to learn more about is the theory behind how such devices work on a basic level, and why they do. The most helpful answer reply I could receive here would include a basic example circuit and an explanation for each component in the circuit i.e why we use that component and why the circuit wouldn't work without it. Subsequently I would be interested to know how you could make such a basic device have more power or range (so in other words, how to we step it up from something that can break a watch to something that destroys every computer in the room? What about every computer in the street? etc.) Understanding this subject is bound to require some general knowledge of electronics that I don't have, but don't worry - that's the point; I'm here to learn that stuff too. If you notice that I'm missing some obvious electronics knowledge, of course feel free to point that out =]
--Research I've already done
I've found various DIY EMP device tutorials online, and most of these use camera flash circuits. The problem is that none of them really go into any detail about why they use a camera flash circuit (I imagine it's because they can hold a big charge, but as I say by knowledge is basic and I can't be sure). They also use a coil of copper wire in most cases, and again, I don't have an explanation for this; I don't know why it helps to coil wire in a circuit. I suppose it's just some part of foundational electronics that I haven't picked up yet. Also, I think it'd probably be a stupid idea to make such a device with an Arduino kit because it could damage its self, nevertheless, it would be an amazing learning resource for me to see a design for a one shot Arduino EMP device, purely because my electronics experience has all been with Arduino projects so far and I'm not great at reading schematics that don't have a drawing of a breadboard...
Please don't reply only asking why I want to know this stuff. There is another thread I found on this forum, and the only replies were warnings about the legality of making such devices, or the dangers of high voltage devices in the hands of inexperienced people. I really could be doing without begging for a straight answer to my question; suffice it to say I'm just interested in the subject matter, I'm also a fan of the Matrix and other sci-fi where machines are the enemy, and the reason I want to know this is because today this subject is specifically what's driving me to dive deeper into electronics than I have before. The tiny thrill of the malicious nature of the subject is what has me engaged, so I'd like to run with it.
Hopefully my appeal to know this info is satisfactory; I'm an adult, and I'm only planning on breaking a few calculators so please don't be that guy.
An atomic explosion generates a lot of EMP - but it's not a very practical generator.
The basic idea for a practical one is to store a lot of energy as a high voltage in eg a capacitor, and discharge it suddenly into an resonating device and couple the resulting RF power into an efficient antenna. The more suddenly you do it the shorter the pulse and the higher the peak energy radiated . A spark is pretty good at this. A simple piezo gas lighter generates a bit, and if coupled to a radiating antenna would be effective. But not very powerful.
Tesla machines are impressive and generate a fair amount, but it doesn't damage things much.
His idea of using such a device to distribute power efficiently was absolutely nuts - didn't he know the inverse square law?
Any metallic shielding is very good at excludiing rf fields, so damaging electronics in metal boxes would require enormous amoounts of energy.
Yes good yarn but every tine a see a story of a device being smuggled to do something i cant help but wonder how nobody noticed the crane the used to move it.
Thanks @allanhurst - that's a very useful reply. On a side note, Tesla's inventions have always fascinated me. I'm not sure what you're implying by him not knowing the inverse square law? I'm only familiar with this law used to calculate the intensity of sound over distance from its source, not in electronics.
raschemmel:
No, that does not suffice. You sound like a terrorist and I am inclined to send a link to this post to Homeland Security.
Okay, I admit it. I was planning on running into a supermarket with one of these things strapped to my chest and threatening to disable the self service checkouts unless the cost of pot noodles is reduced. Foiled again.
(DISCLAIMER: THAT WAS A JOKE, BUT THE POTENTIAL TO AFFECT PEOPLE'S PACEMAKERS IS VERY SERIOUS. I WOULD NOT EVER USE SUCH AN EMP DEVICE IN PUBLIC OR NEAR OTHER PEOPLE)
Sorry to double post, but just to clarify to others that the specific type of devices I'm interested in are those that fire some kind of charged blast of an electromagnetic field, intended to disable or damage any electrical equipment within a certain radius i.e the kind used to destroy sentinels in The Matrix, only where the sentinels are an iPod or something. I'm not planning on building anything on a Batman scale, no, but I'd sure be fascinated to know how something on a Batman scale would work in real life.
You couldn't afford anything on a large scale - massive amounts of power are needed. Think LHC, nuclear
explosion in space.
Focussing microwaves however is trivial by comparison - that's how radar works and being near a high
power radar transmitter is going to fry most things. Still need to spend a lot of money and use a lot
of power - not sure what surplus high power pulsed TWT's go for, they are probably restricted tech anyhow.
A question like yours was asked of a man called Robert Watson-Watt at the radio research station in Slough in about 1935. Science fiction at that time was full of stories about death rays or disruptor beams and so on , and the British government was sufficiently worried to ask him the question.
His team soon calculated that such a beam was quite impractical because of the vast powers required, but thought that it might be possible to make a device using radio waves which could detect aircraft at a distance.
Destructive EMP devices used in the vicinity of consumer electronics are illegal because they interfere with emergency services equipment. Emergency services operate anywhere there are human beings so that rules out everywhere.
Any device capable of destroying consumer electronicsis considered domestic terrorism.
It should be obvious that all electro-magnetic emissions are controlled by the FCC who maintain a 24/7/365 Response Team to hunt down and confiscate such equipment and arrest those operating it. They should be getting there right about now...If you have any pets I suggest you leave an extra bowl of food out....
Go play with a microwave gun and go overcook people's steaks from a distance.
And work on your manner, at least try to sound less like a terrorist or angsty teen wanting to mess with the guy that a girl you like is dating because you think she should be with your terrorist arse instead.