Power Supply for EMP Gun

[shine222]

Some questions about so called Electromagnetic Pulse (Emp) Gun: has anybody tried to build it? Does it work well?
Not clear about antenna: is it like omnidirectional antenna and radiate in all directions, or mainly directional antena with main beam? Is it possible make directional beam, say 5 x 5 inch?
Can the Power Supply be a battery-powered? What type of battery can be used in this Power Supply?
note: See description attached

 

[MikeMl]

Since the circuit at best seems to put out a single pulse at a frequency in the low hundreds of MHz at a power level of a few tens of watts, I cant figure out how it is supposed vaporize ICs? My 75W VHF/UHF transmitter doesn't do it. Building a highly directional antenna at VHF/UHF frequencies is possible, but it has to be 10s of meters in aperture. You would have to get to 10s of GHz to make a highly directional antenna/beam that is only 6 inches by 6 inches

 

[crutschow]

For that small an antenna you would likely need a centimeter-wave high power oscillator such as a magnetron, typically used in radar or microwave applications, that can output a kW or more pulse of power. Of course these operate from very high voltages and the output signal can zap a person as well as other stuff.

 

[shine222]

the frequency is ~100MHz. Using magnetron probably not possible, since I need portable device, that powered by some standard battery(s).

 

[Blueteeth]

the frequency is ~100MHz. Using magnetron probably not possible, since I need portable device, that powered by some standard battery(s).

You 'need' a portable device? Since when do peoeple need a device which can destroy electronics at a distance?

Hmm, there have been a few tabletop devices which behave as crude 'emp' (they're not actually EMP's at all) and even with high output power, didn't do much damage unless some unsheilded electronics was within ten feet.

What exactly are you trying to do?

 

[Mr RB]

Use a sledgehammer instead. If you are going to commit criminal acts of vandalism at least you will be more effective at it.

 

[Mikebits]

That pdf is a joke. Get real, I mean really. In the first paragraph it states that it generates kilowatts of power from a small battery. Oh really? I guess universal laws of physics and electronics cease to exist for this device. It is a scam plain and simple.

 

[Sceadwian]

mike, kilowats of PEAK pulse power =) It's basically discharging a current pulse through a high Q LC resonant circuit. It might cause ticks on AM radio, I'd hardly call it a gun though. And it would be very illegal to use, it would at best be mildly irritating to a few nearby people. Please don't try to do such projects, there is no lawful reason for it and the practicalities of it are not something you should be playing with in the first place.

 

[Blueteeth]

Practicalities? Even if it was much mroe powerful, I can't see any practical use for it.

 

[tcmtech]

The spark gap on my Tesla coil is powered a 60 MA 12 KV neon sign transformer on tuned LC tank and it has yet to ever damage any type of electronics even at very close range.
I have taken pictures of it many times with my digital camera from less than a foot away with no ill effects to it.

To do actual damage to actual circuitry takes far more power than what I have available.

 

[Sceadwian]

Right blueteeth, that's what I ment =) the practicalities are they don't work practically.
Actually tcmtech it doesn't, it just takes what you have designed to intentionally radiate.
That's 720 watts of power, you could use (as already discussed) the magnetron of a microwave oven through a waveguide antenna and blow every wi-fi bluetooth within 50 miles and probably a modest number of cell phones or other radio receivers just from overwhelming the receiver circuits.

 

[tcmtech]

Tempting, but microwave oven magnetron's are something I have never turned on outside of the oven itself. I guess thats the one electronics device I am cautious of.
Still the Tesla Coil driver will make my fluorescents flicker in the shed when its going and I do get a fair amount static like sparking in any metallic materials (piles of screws and stuff) thats near it.
Most likely its just inductive effects.

Still as far as EMP generation I have been of the understanding its very application specific and always range limited. Nukes excluded of course!

 

[Sceadwian]

There is some limited refrence on the net on how to do it out there TCM =) The waveguide is nothing more than a squared funnel of the proper dimensions.

By the way, define near it? What's the distance you get a flourescent tube to light up? You should put some CD's near it see what happens.

 

[shine222]

Still as far as EMP generation I have been of the understanding its very application specific and always range limited.

Yes, its right. The aboved EMP device techically isn't very good, agreed. Have anyone better ideas? Basically, the things is simple, and there is nothing impossible. The main thing is electromagnetic theory and correct mathematical calculation. Integrated circuits, transistors, inductive components can be neutralized (destroyed) by power EMP impulses with appropriate frequency, amplitude, and phase. For my project, I am interesting in short range device, target distance is 10-inch, portable, powered by batteries.

 

[Dragon Tamer]

the US military is just getting started with EMP, and something like this comes out? i think you have a better chance of using a taser for you're specific needs than this do-dad that does who knows what. if you are looking for an electromagnetic device for theory purposes then do what tcmtech did, make a Tesla coil. if you are interested in destroying stuff illegaly, there are three ways to do it, take a sledge hammer to it (like Mr RB said) you could short it out with a screwdriver or something, or you could increase that particular supply voltage to an amount that would make most of us on this site cry with pride.

 

[gary350]

I have built an EMP and it works. All it is, is a capacitor bank that discharges into a coil of wire. The coil produces a very powerful magnetic pulse. A strong magnet pulse will generate high voltages in semiconductor devices causing them to burn out.

I have a bridge rectifier that I can plug into the wall with a cord. I have a current limiting resistor in the 120 Volt AC line to keep surge current from killing the bridge rectifier. This converts the 120 VAC into 120 x 1.414 = 169.7 volts DC. I use this to charge 2 capacitors that are wired in parallel. The 2 electrolitic caps are rated 200 volt DC about 7400 uf.

I wound my own pancake coil with #24 enamel coated copper wire. The coil is 1/4" thick 5" diameter about 1000 turns of wire coated with polyurethane varnish.

Discharge the cap bank into the coil it produces a very powerful magnetic pulse. I have a very high amp push button switch to dischaged the cap bank into the coil. A low amp switch will weld the contacts together.

The charger circuit inside of a (throw away camera) can be used to charge the cap bank too and make this device portable. A D cell battery works best instead of the intended AAA battery. It is a slow charge. If you can get your hands on about 10 of these throw away camera circuit board use 10 of those charger circuit boards in parallel to charge the cap bank 10 times faster.

Charge the cap bank, push the button and discharge it through the coil, it will kill any cell phone within 3 feet. It will kill a calculator, transistor radio and any solid state transistor device within 3 feet.

There is lots of hostility to ill mannered people using cell phones in public places! I totally despise mindless gabbling, where you can't escape, or the bad manners of people of all ages who seem to think their affairs (literal as well as figurative) will interest all within hearing range. They even raise their voices, so everyone can hear. How nice! Just walk past some loud mouth jerk with a cell phone and push the kill button it solves the problem every time.

I think a large diameter pancake coil and a larger cap bank will give this a longer range.

 

[shine222]

the US military is just getting started with EMP, and something like this comes out?

As far I know, the police uses sort of EMP generators for a long time, to stop a car at a distance. As to the rest, I'm not sure I understand you.

 

[MikeMl]

..., and there is nothing impossible. ...

Just violating the Laws of Thermodynamics, basic electrical laws, Maxwell's equations, etc.

 

[shine222]

Just violating the Laws of Thermodynamics, basic electrical laws, Maxwell's equations, etc.

which specifically? You want to say, that powerful rectangular EMP impulses can no disrupt sensitive electronic devices when these impulses generated close to target?(~5-inch)

 

[shine222]

We need to couple a Marx generator to an antenna.