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What you need to know about EMP weapons

aardvark.co.nz

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Re: What you need to know about EMP weapons

#191

Post by genewitch »

lostlogin wrote: post #188
genewitch wrote: post #184

Earlier quoted context omitted.

126-128MHz if i am reading what you said correctly is aviation (aircraft use 108-136MHz, AM) - but i am unsure of what that notation means and the AI explanation made my eyes glaze. I'm unsure why the FCC wouldn't be the ones to complain; but i've never managed to annoy a government with my radio-work yet, so i am not sure who calls who to send someone to knock on the door. either way https://www.ntia.gov/sites/defau…

> I'm unsure why the FCC wouldn't be the ones to complain Are you mentioned - US only. I’m in New Zealand.

https://www.rsm.govt.nz/assets/Uploads/documents/radio-spect...

as far as why the coast guard, that's a dive too deep for me today. Interesting story, though, on your part!

Re: What you need to know about EMP weapons

#192

Post by magicalhippo »

ianburrell wrote: post #103
nancyminusone wrote: post #62

>You can also forget about the inverse square law to protect you No, you don't get to ignore physics because the source is not a point source >Very large area of EMP How large? >Induces currents in any conducting material So does a magnet falling off my fridge. What magnitude of currents, at what distance, in what sized conductor? >During E1 the frequencies are so high How high are they? There can be radio waves stro…

My understanding is that nearby nuke and high altitude produce different EMP. The nearby one destroys electronic, but less of concern since close to nuclear blast. The high altitude one covers a large area, but it is more like solar flare, causing current in large conductors and primarily affecting the grid. The problem is that the recent government studies that say high altitude can hurt electronics are all made by…

> The problem is that the recent government studies that say high altitude can hurt electronics are all made by alarmists.

Was just thinking about how electronics back in the 80s and 90s tended to die from static electricity and similar very often, as they didn't have much built-in protection.

These days almost all transistors and microcontrollers have built-in overvoltage protection, and all serious circuits adds additional external protection like TVS diodes and such, especially for anything connected to cables (which would act as antennas).

So I'm guessing the area which an EMP is effective could be lower these days compared to back in the 80s and 90s?

Re: What you need to know about EMP weapons

#193

Post by sbierwagen »

jerlam wrote: post #140
sbierwagen wrote: post #52

Earlier quoted context omitted.

I read it and was not impressed. It starts with North Korea launching two ICBMs against DC and a nuclear plant in California. Interceptors fail and the warheads hit their targets. This is unlikely, but possible. The launch is explicitly irrational, the act of a mad dictator. In response, the US counterstrikes with Minuteman, despite having perfectly serviceable air deliverable nukes. Russia detects the launch, and th…

A similar book of this category may be The 2020 Commission Report on the North Korean Nuclear Attacks Against the United States which describes how a series of events, which have separately happened in the past, may lead to NK launching nukes. But it is not framed as the irrational actions of a mad dictator, but a series of coincidences that suggest NK was itself being attacked. It was not fun seeing the saber-rattli…

Yes, 2020 was much better, despite the scattering of Orange Man Bad that the author couldn't help from inserting.

One important thing is that the US's response to NK in that book was non-nuclear. They can kill millions of Americans but they are not actually an existential threat. The US did not use nuclear weapons on Afghanistan after 9/11, they used conventional explosives.

Another is that, according to 2020 at least, the North does not have a very robust nuclear command and control communications system, or, being a small country, much in the way of space surveillance assets. They apparently use regular cell phones and commercial imagery.

One of the unfortunate coincidences that kick off the nuclear launch is that the cell phone network is overloaded after South Korea does a missile strike on one of the dictator's residences. From NK's view, missile strikes on official residences and the abrupt collapse of communications, with no reliable information from the outside world, mean that a NATO decapitation strike is underway, so they launch the missiles before they lose them. You wouldn't have the same scenario in the US, simply because we have so many more nuclear weapons and a much longer nuclear command line of succession that a decapitation attack with conventional weapons would take millions of cruise missiles. (North Korea has no backup dictator, while the US has 18 people in the order of succession.)

Re: What you need to know about EMP weapons

#194

Post by hxorr »

ufmace wrote: post #178
hxorr wrote: post #160

Earlier quoted context omitted.

I happen to be from the same town as this guy. He is well known for building his own ramjet-powered cruise missile. I don't know about recently but he was actively involved in the local RC airplane club for quite a while if I recall correctly. His website is well worth checking out, he has a very extensive technical knowledge.

Okay, that's very cool! I don't mean to trash this guy at all, he may well be a real expert in some fields. However, it is a failure mode that people who are really smart and qualified about one thing can assume they are equally smart and qualified about a bunch of other fields that require their own specific expertise. Alas, it doesn't work that way. There's nothing wrong with not knowing about some specific technic…

I fully agree with you and have unfortunately seen this happen with a number of youtubers I follow as their channel and influence has grown.

Re: What you need to know about EMP weapons

#195

Post by wat10000 »

southernplaces7 wrote: post #190
wat10000 wrote: post #147

Earlier quoted context omitted.

Mild spoilers here, I suppose! It didn’t make sense that San Antonio would be targeted in the limited Soviet strike. It would be pretty far down the list, definitely not in the top 3. I believe Streiber has said as much, and that it was included because of the personal connection, and the reason given in the book (some military headquarters there?) was a weak excuse. I can’t quite explain it, but it doesn’t feel righ…

Hmm, good points, but for the first one at least, the way I saw it was that the intended Soviet nuclear strike was supposed to be total, meaning hundreds of warheads for hundreds of targets, maybe even thousands for thousands. That only a few actually landed was because of problems with Soviet strike capacity and of those few that got through, which ones actually did was mostly a question of random bad luck, so I jus…

I checked and it seems like the reason for San Antonio was a mix of your view and mine (assuming we can believe the narrator here):

“At that time I got a look at the condition of San Antonio. I remember being astonished that this little city had been so terribly devastated on Warday. People had hardly even heard of it in Britain. One would have expected Los Angeles or even Houston before San Antonio. Of course, it has since come out that a good part of the planned Soviet attack didn't go off, so in a sense San Antonio was simply unlucky. The Soviets had given it first-strike priority because of the extensive U.S. Air Force repair and refitting facilities there, and the huge complex of military hospitals, the atomic supplies dump at Medina Base, and the presence of a mechanized army that could have been used to preserve order across the whole of the Southwest as well as seal the Mexican border.”

So the first strike was those three cities, and then the followup total strike didn’t happen, presumably stopped by the US counterstrike.

For Manhattan, it says that the biggest hazard is from chemical pollution from abandoned storage facilities, particularly nearby in New Jersey. Which seems kind of plausible, although I imagine people would be a lot more tolerant of such health hazards in this world. I guess everyone evacuated, and then the fact that you can’t just walk back to Manhattan might keep people from returning.

Re: What you need to know about EMP weapons

#196

Post by jcrawfordor »

genewitch wrote: post #181
jcrawfordor wrote: post #121

Earlier quoted context omitted.

It should be understood that the largest impact of the Starfish Prime test, knocking out streetlights, was the result of a very specific design detail of the street lights that is now quite antiquated (they were high-voltage, constant-current loops with carbon disc arc-over cutouts, and the EMP seems to have caused some combination of direct induced voltage and disregulation of the constant current power supply that…

LEDs use constant current drivers, though. And even if you disagree, LEDs need to be current limited, so something will break with a large pulse of current, the driver or the LEDs themselves. Maybe sodium lights are immune, in isolation?

the constant-current drivers in LED lighting are a very different concept from constant-current lighting circuits, which are a ~1920s technology rarely seen today. constant-current lighting circuits can be miles long, operate at up to 1kV or so, and require some type of cut-out/bypass feature at each individual light so that a failure of a single bulb does not take the entire circuit out. The problems that constant-current lighting circuits address (maximizing the life of incandescent bulbs) are all solved in different, more robust ways in modern lighting systems. Most significantly, the carbon-disc cutouts that were the direct cause of the street lighting failures are no longer used (even in legacy constant-current lighting systems, where they have been replaced with more modern devices).

Re: What you need to know about EMP weapons

#197

Post by rurban »

Calwestjobs wrote: post #63
tomxor wrote: post #15

> wrap that in aluminium foil, making sure that the ends are folded over and pressed down hard to provide good inter-layer contact I've tried this many times, it's impossible to prevent gaps without welding it shut. Obviously I wasn't testing with an EMP or nuke, but trying to block 2.4GHz WiFi... But that is well within the E1 range the author states. I think the problem with folding is it's too uniform, it's still…

1. google how many lightning strikes are there per day 2. google how many millions of miles/kilometers of electric wires is hanging in air all over the world providing people with electricity 3. do not google how many of those millions of lightning strikes PER DAY disabled those billions of miles of wires per day, by applying energy bigger than nuclear EMP. do not google that.

You don't need to google. Simple experience tells you which continent is well prepared to EMP problems, and which not. Where do you have to protect your consumer electronics from lightning strikes and where not? In Europe and Russia you don't have to.

Re: What you need to know about EMP weapons

#198

Post by resters »

timewizard wrote: post #186
resters wrote: post #170

Earlier quoted context omitted.

Communications equipment is not designed to withstand lightning strikes. Lightning protection is meant to prevent the tower from melting or the building from burning down, not to protect a receiver!

I'm not at all sure why you'd think that. Here's an actual product that sits inline with the coaxial cable and is absolutely intended to protect the receiver. https://www.dxengineering.com/parts/ntk-pti-bb50nff?seid=dxe...

Serious HEMP protectors are tested to MIL-STD-188-125 or IEC 61000-2-10

Re: What you need to know about EMP weapons

#199

Post by mkfs »

euroderf wrote: post #189
spacebanana7 wrote: post #93

Earlier quoted context omitted.

The USA did it against Japan. Of course those were special circumstances, but all wars have their own set of special circumstances to some extent. There’s also the argument that using nuclear weapons make sense when a nuclear state has a weaker conventional force that its opponent. Russia still has a pretty strong conventional force, but for example North Korea is in this position against most likely adversaries.

> There’s also the argument that using nuclear weapons make sense when a nuclear state has a weaker conventional force that its opponent. Facing the Warsaw Pact, the US never renounced first use of nuclear weapons.

Which is actually quite unfortunate, given that China, our closest rival, has an avowed "no first use" policy. Sanctity of human life and fundamental reciprocity would behoove us to at least, with respect to them, adopt an equivalent posture.

Re: What you need to know about EMP weapons

#200

Post by euroderf »

mkfs wrote: post #199
euroderf wrote: post #189

Earlier quoted context omitted.

> There’s also the argument that using nuclear weapons make sense when a nuclear state has a weaker conventional force that its opponent. Facing the Warsaw Pact, the US never renounced first use of nuclear weapons.

Which is actually quite unfortunate, given that China, our closest rival, has an avowed "no first use" policy. Sanctity of human life and fundamental reciprocity would behoove us to at least, with respect to them, adopt an equivalent posture.

One might counterargue that in a fair fight (i.e. all-conventional), China might clean our clocks. And they certainly have lots of domestic political reasons to start a wholly unnecessary war.
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