How would one construct such a thing?
I tried to find relevant information but all I found was game crap.
Any theory on the subject might help me too.
I want to try and build something like it, for the great challenge and for the fun of it's use (if it doesn't take all the city's power to use)
and I came to think of, you need not my reasons.

- KjeXz

There was an article in Popular Science about a year ago about a new EMP bomb. I seem completly incapable to find it on their website though.

The basic theory is simple enough. What is needed is to create a cascading short circut with a high amount of current.

Keep in mind that the structure I am about to describe require precision engineering well beyond the scope of the home hobbiest.

The first part is powering the beast. A standard off the shelf set of car batteries should do the trick nicely. Though if you want to reduce mass it can also be built with an extension cord. Not practical if you are dropping it on a city, but just fine if you want to create a city wide panic.

The source of the power isn't important, what is important is the raw wattage available. Because it is used to power the capacitor bank. The purpose of the capacitor bank is to store the electricty, and release a massive discharge when needed. This discharge alone would power a small EMP when run through an elecromagnet coil. But who wants a small EMP?


Now for the coil. This is the tricky part. While the rough plans were given in Popular Science I was able to spot the flaws intended to keep amatures from building one. I present to you the error free part.

The Core
The core is a peice of copper tubing. It is on the negitive side of the current and is wired to the capacitor bank. It is also filled with explosives. The purpose of the explosives is not to blow up the tubing, but to cause it to expand rapidly starting at the end away from where it is wired to the capacitor bank, and rapidly prgressing towards it. This is the physical movement that causes the cascading short circut. There are two important factors, the speed at which the ripple of expanding metal travels and the fact that the ripple has to move smoothly, and be perfectly concentric the whole time. I do not know if the tubing is destroyed by the explosion, it would depend on several factors, which are not important at this point. (Remember, this is about basic theory, you have to figure out the details yourself if you want to build one.)

The Coil
This is the trickiest part, though in theory it is simple. When the core ripples, it comes in contact with the far end of the coil and progresses down the coil gaining less and less resistance the whole time. This is what actualy causes the EMP. The coil must be wraped around the core, but it can not touch the core or itself. But the closer it is to the core and the tighter the coils are (increasing overall distance and ripple speed along the wire) the better it will work. For construction of the coil I would recomend that the coil is created by wrapping wire around a cylinder just a hair wider than the core. The wire should be enameled along it's length, exept for the underside which will come in contact with the core during use. Enameling it will insulate the coils from each other without adding the bulk of other insulations. Once the coil itself is complete a stiff casing should be bonded to the outside to prevent anything from coming out of place. There are many types of plastic that would probably work, but for sheer stiffness (an absolute nessity) I recomend a resin cast.

When assembeling the core and the coil the utmost care must be taken, because if the coil is scratched or dented in any place it may not work properly. If it takes an hour to insert it, so be it.

Lining up the core and the coil is also tricky. The coil should be mounted in whatever the final casing is to be before trying this. By mounting the core on screws, which are in turn mounted in the case, you should have the percision needed to line it up. By running a small current through the coil and the core you can determine if it is touching, and with a votage meter and a calculator you can determine where. If it is anywhere but at the ends you will have to rebuild the whole damn thing. Once it is lined up so that it is not touching, you can gradualy increase the voltage until it sparks. You can either try adjusting it more to stop the sparking, or you can set your capacitor bank below the voltage level that causes it to spark. Adjusting it can be a finnicky process, but the more voltage you can put through it the more powerful it will be.


There is your EMP bomb.

so how do you set it off? just plug it in adn when a spark goes it will ignite the core explusives? or is ther ea fuse adn when the explosive go off the capaciter releases? i'm not that smart and this looks interesting

First the circut has to be charged, then the explosives have to be set off. I thought that was fairl obvious.

Bravo, prometheus.

quote:

---

Originally posted by Prometheus:
First the circut has to be charged.

---

How would you charge it? Capacitors? Batteries? A huge-ass generator?
How much power would one of these need?
(BZZT! NEED! INPUT!)

Read what I wrote. As much voltage as you can get without creating an uncontroled short circut. Yes use freaking capacitors, what do you think they're there for?

Please people, if you keep asking for answers then don't read them, I'm going to stop giving them.

heh poor prometheus trying too explain directions too peeps who dont seem to quite fully grasp the concept.