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A question for the EMP Experts on the forum. If a piece of electronics gear is off, will an EMP burst still fry it?
 

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I'm not an expert on EMP, but I'm pretty sure modern electronics will get fried by a burst regardless of if it is off or not. At least stuff that has tiny logic gates in it like microchips. These kinds of components get damaged even by static electricity, though sometimes the damage will only make it degrade faster over time. I assume older electronics without any kind of transistors (like stuff based on vacuum tubes) in them will be more resistant.

Not sure if EMP is that big of a risk in general, but you could build a Faraday cage for the electronics you would like to protect just in case :)
 

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+1 on yes, also not an expert on emp but an electrical engineer, as the name implies EMP (Electro-Magnetic Pulse) is a source of electrical energy therefore whether on/off, plugged in or not electronics will be fried. As monsterdog said, build a very Faraday cage for the electronics you wish to protect and make absolutely certain it is thoroughly grounded otherwise it's a waste of time and materials.
 

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Not a expert either, but I work with high power RF stuff.

Basically, equipment is very vulnerable if it's plugged into the electric grid, as the power lines act like miles and miles of antenna collecting the pulse. Don't expect normal surge protectors to be adaquate to protect electronics, either.

Stuff like cell phones, which have antennas, are going to collect more energy from a pulse than say, a wristwatch, so even if they have the same kinds of transistors inside the phone would be more likely to be damaged.

Even if your cell phone makes it thru a EMP intact, you've really got to wonder how much use it's going to be, as all the cell towers (with antennas, plugged into the electric grid) will be fried.

Stuff like Aimpoints and the like should surtvive any nuke that isn't close enough to kill you first.

H
 

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EDIT: After reading the comments on the referenced article, it seems a MW oven is not really a great idea since it is rather leaky.

If the electronics you wish to protect are small enough, a microwave oven is designed as a Faraday cage. As long as you keep it grounded like SeaMac said. I do not know if the ground plug on the power cable would serve this function or not, so you would need to figure out how to properly ground it.

I don't know if this blog post's author is an expert on EMP either, but it sounds plausible to a layman:
http://modernsurvivalblog.com/emp-electro-magnetic-pulse/microwave-oven-used-as-a-faraday-cage/

As Halmbarte said, cell phones would be pretty pointless to protect, but maybe something like a twoway set of radios to communicate with a partner or a handheld ham radio (make sure you get a license before picking one up) would be good to have for local communications or to try and reach beyond the affected area.
 

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Yes if it is turned off it has a better chance then being turned on. It depends on the electronic device and the proximity to the pulse. Simple electronics should be fine. Toaster oven, ect. The best way to know if something is EMP safe is to think of it like this. If lighting hits your house will the device get destroyed or if you were to open the device and touch it with a static charge(ESD) will it break. Also most laptop computers these days have shielding...not for EMP attack but to shield it from disrupting other electronics. Oh yeah one more thing if the EMP pulse is large enough to take out a city its from a nuclear explosion. So who care's you're probably dead. The one exception is a large solar flare.
 

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The grounding conductor/prong in the cord for a microwave oven would sufficiently ground the microwave's built-in faraday cage provided the receptacle it's plugged into is also properly grounded. Most modern residential structures provide three paths to ground they are service, cold water and slab/foundation if all are installed and functioning as designed a microwave oven should work. It should go without saying, if we are subject to a natural or manmade EMP we have bigger problems than we think.


If the electronics you wish to protect are small enough, a microwave oven is designed as a Faraday cage. As long as you keep it grounded like SeaMac said. I do not know if the ground plug on the power cable would serve this function or not, so you would need to figure out how to properly ground it.

As Halmbarte said, cell phones would be pretty pointless to protect, but maybe something like a twoway set of radios or a handheld ham radio (make sure you get a license before picking one up) would be good to have for local communications or to try and reach beyond the affected area.
 

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Not an "expert" but experienced in the subject.

The right answer is "it depends."

It depends foremost on what type of EMP you're talking about. all Electromagnetic Pulses are not created the same. For example, lightning is an EMP. Lighting strikes a tree a mile from your house? May or may not cause issues, most likely not. Lightning strikes the transformer outside your house? Bigger issue!

Having devices off and unplugged can certainly help depending on the type, location and strength of the EMP.

That said, for the "movie plot" type EMP event (e.g. NEMP or HEMP where you are directly in the AOE), most anything electronic is going to be non-functional unless it's incased in metal and/or a faraday cage.

For most of us, if you're trying to protect a bit of small sensitive electronics, e.g. a battery charger, stashing in a (metal obv) ammo can is a good way to shield them from most anything you'd reasonably expect to encounter.

A couple good resources for reading:

Preparing for EMP and DEW -- A Layman's Guide, by Joel Ho - SurvivalBlog.com

Guest Article: EMP Myths and FAQs, by Joel Ho - SurvivalBlog.com

https://en.wikipedia.org/wiki/Electromagnetic_pulse
 

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This can be misleading, true if it's a toaster which is a resistive load like water heaters and ovens it may survive but an EMP is the source of its own electricity with an exceptionally high joule rating, it is very unlikely whether plugged in or not that any sensitive electronic will survive without a source of protection. Then again if we experience an EMP event we have much bigger things to be concerned with.


Yes if it is turned off it has a better chance then being turned on.
 

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This is a great subject, these kinds of questions make you learn things fast :) From what I can quickly deduce, your Faraday cage does not need to be grounded to shield against EM radiation, only from actual current. Also you cannot have holes that are larger than the wavelength you are trying to protect from. The latter is why a microwave would not work too great, because there are leaks around the edges and where stuff like the lamp is put in.

It would be interesting to see if this type of cheap and easy homemade Faraday cage would cancel out (or not) a wifi signal (shorter wavelength) for instance:


Sure looks easier to set up than an old microwave oven :)
 

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Stuff like cell phones, which have antennas, are going to collect more energy from a pulse than say, a wristwatch, so even if they have the same kinds of transistors inside the phone would be more likely to be damaged.
Surprisingly this is not (supposedly) the case.

Most cell phones will have internal RF shielding to keep parts from interfering with each other that will help to reduce if not eliminate EMP effect.

e.g. as I understand it, your cell phone is probably more likely to make it through an EMP than your (electronic) watch. And both are much more likely to make it through than something like the cheap battery charger that came with your rechargeable batteries :)
 

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Another thing is, if you're concerned about smaller electronics, how would you protect your car?

Most modern vehicles would not work without the electronics inside. Your only real protection would be to drive something from the 60s/70s without fuel injection or perhaps a slightly newer motorcycle.
 

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Another thing is, if you're concerned about smaller electronics, how would you protect your car?

Most modern vehicles would not work without the electronics inside. Your only real protection would be to drive something from the 60s/70s without fuel injection or perhaps a slightly newer motorcycle.
Quite a few in depth studies that say EMP has little to no effect on a car.

See:
How To Prepare Your Car To Handle An EMP And Why You Shouldn't Bother

http://www.survivalblog.com/2010/08/real_world_emp_effects_on_moto.html

Most cars will not even stall. In a test, where cars were subjected to EMP conditions, they tested both with cars turned ON, and cars turned OFF. I quote "No effects were subsequently observed in those automobiles that were not turned on during EMP exposure." NO EFFECTS FOR CARS THAT WERE TURNED OFF during the EMP, they just started right up.

EMP effects on cars that are running: "The most serious effect observed on running automobiles was that the motors in three cars stopped at field strengths of approximately 30 kV/m or above. In an actual EMP exposure, these vehicles would glide to a stop and require the driver to restart them." In other words, 90% of the cars would not even stall if they were running when an EMP happened. There were some further effects, blinking dashboard lights on some cars, etc.., read the report to see them described. Over 20% of cars experienced NO effects while running, not even burnt out radios, and to reiterate, for the cars that were OFF, there were NO effects.

Here's the conclusion of the commission for trucks: "Of the trucks that were not running during EMP exposure, none were subsequently affected during our test. Thirteen of the 18 trucks exhibited a response while running. Most seriously, three of the truck motors stopped. Two could be restarted immediately, but one required towing to a garage for repair. The other 10 trucks that responded exhibited relatively minor temporary responses that did not require driver intervention to correct. Five of the 18 trucks tested did not exhibit any anomalous response up to field strengths of approximately 50 kV/m."
 

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Build or buy a vehicle with a mechanically injected diesel and manual transmission, nothing electrical, no real need for a battery so long as you park on a modest incline and shielded alternators are available for lighting. In a pinch you can even use vegetable oil for fuel.


Another thing is, if you're concerned about smaller electronics, how would you protect your car?

Most modern vehicles would not work without the electronics inside. Your only real protection would be to drive something from the 60s/70s without fuel injection or perhaps a slightly newer motorcycle.
 

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Would a good thick gunsafe work as shielding. Say maybe 1/4 Inch thick with 3/8 door?
For almost all scenarios you can dream up (and be inside survivable radius on), yes, anything inside a gunsafe would be just fine.

Anything inside a metal ammo can is fine, for that matter.
 

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You betcha.

Extreme Cliffs Notes for anyone who doesn't feel like even digesting the 50 page executive summary:

A serious EMP would be really bad for the US. The biggest weakness in in the power grid. The miles of wires basically act as giant antenna. Telecommunications infrastructure is the second largest weakness. Generally speaking, infrastructural weaknesses are the biggest issue, as opposed to frying individual devices. Surprisingly a lot of consumer electronics are reasonably shielded, as are things like cars.

A HEMP (high altitude nuke detonated to create an EMP) detonated in the middle of the US could knock out the power grid and telecommunications to the point it would take years to recover.

Generally speaking, from a "survivalist" perspective it's the same challenge whether its EMP or anything else -- it's all (IMO) about being able to survive in a long term grid down scenario, with no power, no running water, and no food deliveries to your local supermarket. Your individual devices (including your car) aren't your biggest issue, but what you will do when you can't get power / water / gas from the grid, followed in short order by retail supplies of food drying up.
 
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