Will this EMP bomb work?
in [Design]
|
From: Tim Wescott on 14 Apr 2010 14:18 Adam Freeman wrote: > > o...(a)uakron.edu wrote: >>>> Steve >>> You may want to look up on the notion of precrime and actus/mens rea. >>> >>> Adam Freeman >> I don't care, that is not the way security works. I Know all about >> preserving the right to learn and the philosophy of education. >> However, you hit the "nutjob" flag in the way you posed the question. > > I've often asked for and sometimes paid for advice on Usenet. It is > you who have read into something which isn't there. > >> Do you realize you just offered to pay for a device that would be a >> potential terrorist tool of choice? > > So is underwear or shoes, apparently. You going to ban those too? > >> Do you realize from a engineering point of view, you asked a absurd >> question? > > How so, young one? I have 30 years of experience in mechanical > engineering and am retired already. > >> Do you realize that in this day and age, no one will answer those >> sort of questions, to a potential threat,in a public forum? > > I asked other such questions in a public forum under different email > aliases. Haven't had any problems from the authorities where I live. > Of course I have an explosives and firearms license. Even paid a > private contractor (found through Usenet) a lot of money to install a > two stage helium gas gun at my farm. I'll bet that if Osama Bin Laden wants advice on USENET he calls himself something 'western', like "Sam Jones" or, well, "Adam Freeman". The point isn't that you can't do it or that you can't ask for help -- just that you _are_ pushing some "nutcase" buttons, as well as "I'm a terrorist looking for naive talent from the enemy" buttons. You shouldn't be _offended_ by folks being concerned about your bona-fides, you should be _comforted_. I can see wanting to do this for curiosity's sake (eccentric, but OK). I can see wanting to do this to develop a product for your home-country military (good). I can see wanting to do this to develop countermeasures (good). I can see wanting to do this to win a bet, or for the puerile joy of blowing out a few racks of electronics (nothing wrong with that). I can see wanting to do this because you're frustrated by the progress of the Teabaggers, and you're going to bomb your local IRS or FBI offices (very bad). I can see wanting to do this because you're an Islamic activist, you're smart enough to know that if you say you're going to kill the infidel with it we won't help (may be good by your lights and your friends', but very bad for me). Etc. So were I to work with you on this (and I probably would contact you off list if I had that expertise) I would consider it to be a moral, ethical, and legal imperative to not actually _deliver_ any help until I'd done some serious background checking. I'd _much_ rather risk offending an over-sensitive prospect than have any risk at all of my name appearing in the paper next to a picture of a big smoking hole complete with body parts. So why get bent out of shape? -- Tim Wescott Control system and signal processing consulting www.wescottdesign.com
From: Adam Freeman on 14 Apr 2010 14:23 Tim Wescott wrote: > Adam Freeman wrote: > > o...(a)uakron.edu wrote: > >> Um, Somebody is gonna want to "know a bit about you for their > >> files." > > > > None of their business. I have broken no law in the jurisdiction I am > > in. > > Anyone in the US, on the other hand, would find that the State > Department probably views an EMP bomb as a defense article*, and would > strongly discourage** US citizens providing technology and support for > the design of defense articles that may be exported improperly. > > Other countries probably have similar views. Cite? > > If you're going to go out in public and offer money for the design of a > defense article, you should expect to be grilled. So you're saying I wouldn't have been grilled if I asked the same question without offering to pay? How bent out of shape is *that*? At the very least a token gesture of appeciation is good. If the helper doesn't want to receive payment because they want to stay anonymous then they can ask that the payment be redirected to a charity of their choice, and I will produce receipts for them.
From: Tim Wescott on 14 Apr 2010 15:01 Adam Freeman wrote: > > Tim Wescott wrote: >> Adam Freeman wrote: >>> o...(a)uakron.edu wrote: >>>> Um, Somebody is gonna want to "know a bit about you for their >>>> files." >>> None of their business. I have broken no law in the jurisdiction I am >>> in. >> Anyone in the US, on the other hand, would find that the State >> Department probably views an EMP bomb as a defense article*, and would >> strongly discourage** US citizens providing technology and support for >> the design of defense articles that may be exported improperly. >> >> Other countries probably have similar views. > > Cite? > >> If you're going to go out in public and offer money for the design of a >> defense article, you should expect to be grilled. > > So you're saying I wouldn't have been grilled if I asked the same > question without offering to pay? How bent out of shape is *that*? No. Jeered at and/or ignored, but not grilled. -- Tim Wescott Control system and signal processing consulting www.wescottdesign.com
From: John Fields on 14 Apr 2010 17:35 On Wed, 14 Apr 2010 04:40:04 -0700 (PDT), Adam Freeman <afreeman526(a)googlemail.com> wrote: >Basically a circuit consisting of an amalgamation of a Marx circuit to >generate the high seed current and an inductor wrapped around an >explosively driven armature. > >http://img651.imageshack.us/img651/3043/empbombj.pdf > >Some questions I had were: >1) How do I find out the precise time the current through the inductor >coil will be maximum, given real conditions (e.g. finite resistances, >inductance of the Marx circuit itself, eddy currents in armature...)? --- Somebody got into this a few years ago... http://www.freeratio.org/thearchives/showthread.php?t=67081 So, since it's old news: Since you'll be dumping a charged cap into an inductance, unless it's critically damped it'll ring at: 1 f = -------------- Hz 2pi sqrt(LC) which is a period of: t = 2pi sqrt(LC) seconds. the maximum current in the circuit will occur 90� after the switch connecting the cap to the inductor is made, which will be at: 2pi sqrt(LC) t = ------------- seconds. 4 If you don't already have it, download a copy of LTspice from: http://www.linear.com/designtools/software/ and run this: Version 4 SHEET 1 880 680 WIRE -112 0 -272 0 WIRE 0 0 -32 0 WIRE 192 0 0 0 WIRE 192 64 192 0 WIRE 144 80 80 80 WIRE 0 176 0 0 WIRE 192 176 192 144 WIRE -272 288 -272 0 WIRE -96 288 -96 48 WIRE 80 288 80 80 WIRE 192 288 192 256 WIRE -272 448 -272 368 WIRE -96 448 -96 368 WIRE -96 448 -272 448 WIRE -48 448 -48 48 WIRE -48 448 -96 448 WIRE 0 448 0 240 WIRE 0 448 -48 448 WIRE 80 448 80 368 WIRE 80 448 0 448 WIRE 144 448 144 128 WIRE 144 448 80 448 WIRE 192 448 192 368 WIRE 192 448 144 448 WIRE -272 544 -272 448 FLAG -272 544 0 SYMBOL ind 176 160 R0 SYMATTR InstName L1 SYMATTR Value 1e-3 SYMBOL cap -16 176 R0 SYMATTR InstName C1 SYMATTR Value 1e-3 SYMBOL sw 192 160 M180 WINDOW 0 32 15 Left 0 WINDOW 3 32 44 Left 0 SYMATTR InstName S1 SYMBOL sw -16 0 M270 WINDOW 0 32 15 Left 0 WINDOW 3 32 44 Left 0 SYMATTR InstName S2 SYMBOL voltage -272 272 R0 WINDOW 0 -42 -1 Left 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 10000 SYMBOL voltage -96 272 R0 WINDOW 0 -55 8 Left 0 WINDOW 3 24 104 Invisible 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V3 SYMATTR Value PULSE(0 1 0 1e-6 1e-6 10) SYMBOL voltage 80 272 R0 WINDOW 0 -55 8 Left 0 WINDOW 3 24 104 Invisible 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value PULSE(0 1 11 1e-6 1e-6 10) SYMBOL res 176 272 R0 SYMATTR InstName R1 SYMATTR Value 1 TEXT -256 480 Left 0 !.model SW SW(Ron=1e-6 Roff=1e7 Vt=0.5Vh=0) TEXT -248 512 Left 0 !.tran 0 20 0 Adjust the strays as required, and you'll probably get a pretty good idea of what you can expect in terms of maximum current. --- >Is this something best found out by experiment and a digital >oscilloscope? --- Since you'll eventually have to go real-world in order to get real data, the answer is: "yes". --- >2) Presumably, the optimal time for the armature to short out the >inductor coils is when the current within it is at a maximum. >Considering that explosives have a finite run up to detonation, how do >I calculate the best time to initiate the explosives? --- Since you now already know how long it's going to take for the the current in the coil to build up to a maximum, all that's left to do is to determine when to initiate the explosive so that as the armature expands it starts shorting out the solenoid's turns when the current is at its peak. --- >3) The explosives used will probably be a cylindrical charge of TNT >with a length of ~10cm and a radius of ~2cm. Will there be any >problems initiating such a small explosive? --- As long as the armature isn't affected by the initiator, I don't think so. --- >4) Do you have any suggestions on how the electromagnetic pulse can be >maximised, with a goal of destroying nearby unshielded electronics? --- Maybe. --- >5) Can you suggest any other design optimisations? --- Maybe. --- >I am willing to provide funds for quality advice if you can provide >evidence of your expertise. --- Email me if you like, with particulars, but be aware that I'm a registered USDoD contractor and I don't do any rogue foolishness. JF
From: Richard on 14 Apr 2010 20:31
On Apr 14, 4:35 pm, John Fields <jfie...(a)austininstruments.com> wrote: > On Wed, 14 Apr 2010 04:40:04 -0700 (PDT), Adam Freeman > > <afreeman...(a)googlemail.com> wrote: > >Basically a circuit consisting of an amalgamation of a Marx circuit to > >generate the high seed current and an inductor wrapped around an > >explosively driven armature. > > >http://img651.imageshack.us/img651/3043/empbombj.pdf > > >Some questions I had were: > >1) How do I find out the precise time the current through the inductor > >coil will be maximum, given real conditions (e.g. finite resistances, > >inductance of the Marx circuit itself, eddy currents in armature...)? > > --- > Somebody got into this a few years ago... > > http://www.freeratio.org/thearchives/showthread.php?t=67081 > > So, since it's old news: > > Since you'll be dumping a charged cap into an inductance, unless it's > critically damped it'll ring at: > > 1 > f = -------------- Hz > 2pi sqrt(LC) > > which is a period of: > > t = 2pi sqrt(LC) seconds. > > the maximum current in the circuit will occur 90° after the switch > connecting the cap to the inductor is made, which will be at: > > 2pi sqrt(LC) > t = ------------- seconds. > 4 > > If you don't already have it, download a copy of LTspice from: > > http://www.linear.com/designtools/software/ > > and run this: > > Version 4 > SHEET 1 880 680 > WIRE -112 0 -272 0 > WIRE 0 0 -32 0 > WIRE 192 0 0 0 > WIRE 192 64 192 0 > WIRE 144 80 80 80 > WIRE 0 176 0 0 > WIRE 192 176 192 144 > WIRE -272 288 -272 0 > WIRE -96 288 -96 48 > WIRE 80 288 80 80 > WIRE 192 288 192 256 > WIRE -272 448 -272 368 > WIRE -96 448 -96 368 > WIRE -96 448 -272 448 > WIRE -48 448 -48 48 > WIRE -48 448 -96 448 > WIRE 0 448 0 240 > WIRE 0 448 -48 448 > WIRE 80 448 80 368 > WIRE 80 448 0 448 > WIRE 144 448 144 128 > WIRE 144 448 80 448 > WIRE 192 448 192 368 > WIRE 192 448 144 448 > WIRE -272 544 -272 448 > FLAG -272 544 0 > SYMBOL ind 176 160 R0 > SYMATTR InstName L1 > SYMATTR Value 1e-3 > SYMBOL cap -16 176 R0 > SYMATTR InstName C1 > SYMATTR Value 1e-3 > SYMBOL sw 192 160 M180 > WINDOW 0 32 15 Left 0 > WINDOW 3 32 44 Left 0 > SYMATTR InstName S1 > SYMBOL sw -16 0 M270 > WINDOW 0 32 15 Left 0 > WINDOW 3 32 44 Left 0 > SYMATTR InstName S2 > SYMBOL voltage -272 272 R0 > WINDOW 0 -42 -1 Left 0 > WINDOW 123 0 0 Left 0 > WINDOW 39 0 0 Left 0 > SYMATTR InstName V1 > SYMATTR Value 10000 > SYMBOL voltage -96 272 R0 > WINDOW 0 -55 8 Left 0 > WINDOW 3 24 104 Invisible 0 > WINDOW 123 0 0 Left 0 > WINDOW 39 0 0 Left 0 > SYMATTR InstName V3 > SYMATTR Value PULSE(0 1 0 1e-6 1e-6 10) > SYMBOL voltage 80 272 R0 > WINDOW 0 -55 8 Left 0 > WINDOW 3 24 104 Invisible 0 > WINDOW 123 0 0 Left 0 > WINDOW 39 0 0 Left 0 > SYMATTR InstName V2 > SYMATTR Value PULSE(0 1 11 1e-6 1e-6 10) > SYMBOL res 176 272 R0 > SYMATTR InstName R1 > SYMATTR Value 1 > TEXT -256 480 Left 0 !.model SW SW(Ron=1e-6 Roff=1e7 Vt=0.5Vh=0) > TEXT -248 512 Left 0 !.tran 0 20 0 > > Adjust the strays as required, and you'll probably get a pretty good > idea of what you can expect in terms of maximum current. > --- > > >Is this something best found out by experiment and a digital > >oscilloscope? > > --- > Since you'll eventually have to go real-world in order to get real data, > the answer is: "yes". > --- > > >2) Presumably, the optimal time for the armature to short out the > >inductor coils is when the current within it is at a maximum. > >Considering that explosives have a finite run up to detonation, how do > >I calculate the best time to initiate the explosives? > > --- > Since you now already know how long it's going to take for the the > current in the coil to build up to a maximum, all that's left to do is > to determine when to initiate the explosive so that as the armature > expands it starts shorting out the solenoid's turns when the current is > at its peak. > --- > > >3) The explosives used will probably be a cylindrical charge of TNT > >with a length of ~10cm and a radius of ~2cm. Will there be any > >problems initiating such a small explosive? > > --- > As long as the armature isn't affected by the initiator, I don't think > so. > --- > > >4) Do you have any suggestions on how the electromagnetic pulse can be > >maximised, with a goal of destroying nearby unshielded electronics? > > --- > Maybe. > --- > > >5) Can you suggest any other design optimisations? > > --- > Maybe. > --- > > >I am willing to provide funds for quality advice if you can provide > >evidence of your expertise. > > --- > Email me if you like, with particulars, but be aware that I'm a > registered USDoD contractor and I don't do any rogue foolishness. > > JF Can we make something that is rechargeable, concealable and capable of killing a disco thumping SUV in traffic? |