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I bought a 1 gallon metal paint can from Lowe's to test as a faraday can. I put my cell phone in it and tried to call it from another line and it wouldn't go through...Is that the true test? only test?
 

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The only true test for a Faraday cage is an EMP.

All you have shown when you can't get a cellphone inside a presumed Faraday Cage to ring is that the "cage" is proof against cellphone signals. Not an EMP.

That said, a sealed metal can, provided that the contents within are insulated from the can itself, should serve as an excellent Faraday cage.

I would trust it.
 

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I bought a 1 gallon metal paint can from Lowe's to test as a faraday can. I put my cell phone in it and tried to call it from another line and it wouldn't go through...Is that the true test? only test?
There really isn't any way to test it. Just because it blocks your cell phone doesn't mean it will have any effect against an EMP.

've seen folks say that a microwave oven would make a good cage because it blocks their cell phone. I put a remote controlled toy in mine and could trigger it from anywhere in the house using the tiny, weak remote. It might block cell signals, but didn't block a wimpy radio remote. Even if it did, that still tells me nothing about whether it would block an EMP or not.
 

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You can test it that way, but all that is required is to block the frequency from going through and metal actually acts like a water dam in which the flow of electricity goes towards the direction of least resistance..towards the ground or a ground. So if you ground your paint can, it will be EMP proof. Primarily a wooden box with a good wire mesh will do the trick too. Or you can put wire mesh around your shed or buy a metal shed and ground the shed to use as an EMP cage.

All metal cans, metal garbage cans, or wire mesh should be grounded good.
 

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You can test it that way, but all that is required is to block the frequency from going through and metal actually acts like a water dam in which the flow of electricity goes towards the direction of least resistance..towards the ground or a ground. So if you ground your paint can, it will be EMP proof. Primarily a wooden box with a good wire mesh will do the trick too. Or you can put wire mesh around your shed or buy a metal shed and ground the shed to use as an EMP cage.

All metal cans, metal garbage cans, or wire mesh should be grounded good.
Do not ground your Faraday Cage.

Many people make the mistake of assuming EMP is like lightning. It's not. All you may do w/ grounding a Faraday Cage, if you do not do it correctly, is draw the pulse TO the items you're trying to protect.

Grounding against EMP is specialized and need be done only on large, room-sized or larger, Faraday cages. The ground has to also be shielded, and unless you know how to do that....BZZZZT!

BTW, here are some links to bone up on EMP:

http://www.futurescience.com/emp/E1-E2-E3.html

http://www.futurescience.com/emp/EMP-myths.html

http://www.futurescience.com/emp.html

http://glasstone.blogspot.com/2006/0...ear-space.html

http://www.futurescience.com/emp/emp-notes.html

http://www.washingtontimes.com/news/...estroy-us-now/

http://www.newsmax.com/KenTimmerman/...6/16/id/400260

http://www.futurescience.com/emp/emp-protection.html
 

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Excellent Answers Already Given And Thank You

If you could place your cell phone, (turned off) inside a .30 cal ammo can and somehow fully insulate the phone from the can, (maybe wood) THEN place the .30 cal can inside a .50 caliber ammo can again insulating the cans from each other....THEN place that can inside a 5 gallon plastic bucket...THEN bury the bucket about 5 feet down...THEN it MIGHT work as a EMP resistant storage procedure. No guarantees. HB of CJ (old coot)

Uncle Sam has the same problem. Testing in real use is kinda difficult, other than computer modeling. But then....after the SHIF, who will there be to cell phone call? The entire cell phone repeater network will be fried. Might be better to bury Ham 2 meter walkie talkies and lots of communication equipment along with needful electronical stuff like RAD meters, nite vision; other needful things. Just a thought. HB
 

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Like most folks here, my head is spinning from the vast amount of (often contradictory) information on EMP's. Everytime I THINK I actually know something concrete, I read something convincing that makes me doubt it.
Anyway, it's my understanding that EMP's are basically a radio wave, as are cell phone signals. So, I'm curious about MikeK's experience with the microwave filtering cell signals, but then allowing a toy remote control signal to pass. This doesn't instill much confidence in the security of a micro-wave oven as an EMP-proof container ( in fact, I'd say it shoots it all to hell).
I'm thinking about testing this further, by placing a small am/fm radio,turned up loud, inside a microwave and seeing if it gets a signal. Then I could try it with a little Motorola walkie-talkie. The same tests could be done with ammo,paint and garbage cans, but I guess it STILL wouldn't be a fool-proof test of whether or not an EMP will get through.
 

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EMP isn't like radio waves, at least not all of it. It's more about it's ability to collapse the earths magnetic field, thus inducing a electrical pulse into almost any electric or electronic piece of equipment. Think of it more like a transformer where by using AC frequencies the electricity jumps across from one side to the other. BY the expansion and contraction of the magnetic field in a transformer the electricity is induced in the secondary windings.

Where EMP is different is the way it creates this induced electricity. Thus the need to explain it with 3 different types of EMP fields. When a nuke explodes it gives off large amounts of gamma radiation. Inside most bombs and power plants the gamma particles have trouble escaping past the metal. But in a properly designed bomb you can loose much of this shielding, thus more gamma radiation escaping. And it's these gamma particles that has the effect on the earths magnetic field. The huge collapse of the magnetic field creates, or induces, a massive amount of electricity into things.

The E-1 part hurts small electronics because of the massive voltage spike. There's no way to prevent this from effecting operating electronic equipment without proper shielding.

Next to occur, in time, is the E-2 portion. This is what induces a huge spike in power lines. Thus messing up most anything plugged into the grid. Even if the equipment is turned off this spike can't be stopped by standard surge suppressors. So this would also effect all electronics and even AC equipment, like motors, if they are plugged in.

E-3 is of a longer duration thus again another spike that effects long power lines.

The collapse and restoration of the earths magnetic fields is what causes the induced voltages.

Prevention can be as simple as not being plugged into the grid. The Faraday cage acting as an insulator from the earths magnetic field. A simple Faraday cage is nothing more then a shield and insulator. What many suggest is a nested cage, or a shield and insulator inside another shield and insulator. Grounding defeating the purpose since the ground line acts as an antenna to pick up the E-2 and E-3 fields.

The biggest thing is both the shielding and insulator have to be complete, no breaks for any radiation to get in. The door on a microwave being a weak point for EMP. The grill in the glass can keep out (in) microwaves but not all other bands of radiation. The seal around the door also not making for a complete shield thus allowing radiation to get in that way too.

The cheapest and most effective nested Faraday cage can be made with simple items, like bubble wrap or plastic bags as an insulator and aluminum foil for shielding. So wrap the equipment in the insulator, then aluminum foil. The another layer of plastic and aluminum to make a nested cage that should protect most everything.

By far the best source I've found is the one Goose3 gave from future science.
http://www.futurescience.com/emp/emp-protection.html
 

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Like most folks here, my head is spinning from the vast amount of (often contradictory) information on EMP's. Everytime I THINK I actually know something concrete, I read something convincing that makes me doubt it.
Anyway, it's my understanding that EMP's are basically a radio wave, as are cell phone signals. So, I'm curious about MikeK's experience with the microwave filtering cell signals, but then allowing a toy remote control signal to pass. This doesn't instill much confidence in the security of a micro-wave oven as an EMP-proof container ( in fact, I'd say it shoots it all to hell).
I'm thinking about testing this further, by placing a small am/fm radio,turned up loud, inside a microwave and seeing if it gets a signal. Then I could try it with a little Motorola walkie-talkie. The same tests could be done with ammo,paint and garbage cans, but I guess it STILL wouldn't be a fool-proof test of whether or not an EMP will get through.
There are two reasons people want a microwave to work as a Faraday Cage (but it doesn't):

First is that they want an easy solution. Second is that it allows one to easily remove items from the supposed protection of the microwave.

The second has been the bugaboo for me. I'd like to have a good Faraday Cage in which I can store things like my Dillon Digital Scale, my Chronograph, battery charger, emergency radios, walkie-talkies, etc. AND be able to easily remove and exercise them, i.e., check the batteries and so on.

There *are* such boxes out there, but they are very expensive for the space they provide.

I have a couple aluminum boxes that were made in the 50's and used for protecting equipment--not from EMP which wasn't at that point known, but against shock and such. They look like so:





They have rubber gaskets which are not sufficient to seal out EMP, so I replaced one of the gaskets with a home-made aluminum gasket made from 1/4" plastic tubing wrapped with aluminum foil and pressed into the gap formerly occupied by the rubber gasket.

I then sanded off the paint from the contact points inside where the gasket contacts the lid and box, so I'd get good electrical connection between them. I checked that with a continuity tester, lid against box. This makes it easier to get in and out of a Faraday Cage, but it's still not large enough for my Chronograph.

I have a couple thin aluminum sheets from which I hope, eventually, to make a larger box out of wood and covered w/ aluminum sheeting, such that the top will press against the bottom, the joint making good electrical contact with no gaps.

I tried this with aluminum tape but failed because I left a tiny gap between the lid and box--cellphone rang (proof that it *wasn't* a sufficent Faraday Cage).

Still working on it. When and if I get something figured out I'll take pics and post them.
 
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EMP isn't like radio waves, at least not all of it. It's more about it's ability to collapse the earths magnetic field, thus inducing a electrical pulse into almost any electric or electronic piece of equipment. Think of it more like a transformer where by using AC frequencies the electricity jumps across from one side to the other. BY the expansion and contraction of the magnetic field in a transformer the electricity is induced in the secondary windings.

Where EMP is different is the way it creates this induced electricity. Thus the need to explain it with 3 different types of EMP fields. When a nuke explodes it gives off large amounts of gamma radiation. Inside most bombs and power plants the gamma particles have trouble escaping past the metal. But in a properly designed bomb you can loose much of this shielding, thus more gamma radiation escaping. And it's these gamma particles that has the effect on the earths magnetic field. The huge collapse of the magnetic field creates, or induces, a massive amount of electricity into things.

The E-1 part hurts small electronics because of the massive voltage spike. There's no way to prevent this from effecting operating electronic equipment without proper shielding.

Next to occur, in time, is the E-2 portion. This is what induces a huge spike in power lines. Thus messing up most anything plugged into the grid. Even if the equipment is turned off this spike can't be stopped by standard surge suppressors. So this would also effect all electronics and even AC equipment, like motors, if they are plugged in.

E-3 is of a longer duration thus again another spike that effects long power lines.

The collapse and restoration of the earths magnetic fields is what causes the induced voltages.

Prevention can be as simple as not being plugged into the grid. The Faraday cage acting as an insulator from the earths magnetic field. A simple Faraday cage is nothing more then a shield and insulator. What many suggest is a nested cage, or a shield and insulator inside another shield and insulator. Grounding defeating the purpose since the ground line acts as an antenna to pick up the E-2 and E-3 fields.

The biggest thing is both the shielding and insulator have to be complete, no breaks for any radiation to get in. The door on a microwave being a weak point for EMP. The grill in the glass can keep out (in) microwaves but not all other bands of radiation. The seal around the door also not making for a complete shield thus allowing radiation to get in that way too.

The cheapest and most effective nested Faraday cage can be made with simple items, like bubble wrap or plastic bags as an insulator and aluminum foil for shielding. So wrap the equipment in the insulator, then aluminum foil. The another layer of plastic and aluminum to make a nested cage that should protect most everything.

By far the best source I've found is the one Goose3 gave from future science.
http://www.futurescience.com/emp/emp-protection.html
That is a great article. It pretty much sums everything I have ever researched about EMP's up in one nice, easy to read and understand, article. It would be wise to read the above mentioned article if you have any questions about EMP's. You might want to print it out also and put it with your books for future reference also.

The above mentioned article also makes a really good point. Say 9 out of 10 electronic devices stop working and the power it out and etc. How will you know exactly what is going on. While most of us would probably understand that an EMP just happened, it is still important to know what is happening around you. That is the reason you need to have a battery, solar, and hand crank shortwave radio in a NESTED faraday cage. The SW radios are not big usually, so it will be easy to construct a simple NESTED faraday cage to protect it. Personally, I have multiple SW radios in nested faraday cages located in my house, under my house, and in the garage/storage area. I also have a couple cached in the ground. My viewpoint is that no one truly know the effect an EMP might have so having redundant SW radios located in different areas will provide the best chance that one of the SW radios made it thru the event unscathed. Once the EMP happens the SW radio is going to be the only means in which to receive info from the government, not that is really matters what .gov has to say, and other continents. Knowing what is going on is the best way to be fully prepared and knowing what to do.

Personally, EMP's scare me. The average person just doesn't understand how vulnerable the USA really is towards an EMP attack. Millions of people would die from multiple different reasons. We would be pushed backwards 500 years. The farther we go into the future where we depend on our fragile infrastructure the worse the risk becomes. I just hope our government does more to protect our infrastructure. If they don't we could be in a world of hurt. Read the article above, you won't be sorry.

:thumb:
 

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I will admit this is a subject that doesnt concern me much. I would prefer a simpler time without all the electronics. ( I realize how handy some would be, just not interested )

Why not double up? You could even ground the outside one. Cover all your bases since no one is sure anyway? Even wrap your components separately in layers?
 

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I will admit this is a subject that doesnt concern me much. I would prefer a simpler time without all the electronics. ( I realize how handy some would be, just not interested )

Why not double up? You could even ground the outside one. Cover all your bases since no one is sure anyway? Even wrap your components separately in layers?

Why it bothers me is all it takes is some 3rd world wannabe, like North Korea, to put a rather small nuke rocket on a ship, float it to with 50 mile of our country and shoot it into the air and have it explode.(pretty much the current state or rocket technology in North Korea now.) no need for pinpoint accuracy since the emp field will cover a far greater area then hitting a city with a bomb. And do far greater damage since we rely on electricity for almost everything.

Use one over the east and west coast (or one well placed one over the center of the country) and you'll pretty much put our country literally back into the stone age. There would be no recovery for a very long time. Heck, there's already a 3 year waiting list for the type transformers we use in substations. Knock most of them out and we may never see the parts get here.

About the only things that would be ready for this is some of our government and military. For the rest of us we'd be SOL.


It's not like going back 100 years with the lack of technology but that the entire infrastructure requires electricity. And that, for the most part, would be gone. Think about all the things you do, and your job, and see if you can figure out where electricity is needed for it.

Refineries, for fuel, gone. So even if your car runs there's no gasoline to buy.
Food needs that same fuel to get it to market
Potable water, for the most part, can't be made without it.

So, no food or water. No fuel for transportation or heating and cooling. Most jobs gone. And millions of people thirsty, hungry and possibly freezing.

Sounds like a picnic.

Yeah, nothing to worry about. :rolleyes:

And all from one relatively small nuke bomb.
 
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I admit I'm not one to be concerned with EMP. How can I place a cell phone call when the infrastructure's been wiped out by EMP? How can I power ANY electrical device when the infrastructure's been wiped out by EMP?

In order to make it worth my effort to shield against EMP, I'd also have to shield a power generating system against EMP. So now I'm storing batteries and solar/wind equipment in a faraday cage that I can't use until the EMP attack is over with.

You know what's impervious to EMP? Water storage, gardens, other food storage, toilet paper, etc. I'll put money and time into those things way before I worry about protecting stuff against EMP.
 

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I admit, I USED to be relatively unconcerned about EMP's, but the more I read, the more I realized how vulnerable we are to it,how easy it would be for any number of our enemies to send us back to the middle ages, and the fact that THEY KNOW THIS. To dismiss this entirely is just plain stupid.Period.
Sure, there are aspects of this threat that we can't protect oursleves from, but there are a couple practical things we can and should do,at the personal level. If nothing else, imagine what a God-send a few flashlights would be if there was no electricity? And imagine how stupid and ill-prepared you'd feel if we DID get EMP'd, and you're sitting on a several expensive,high quality LED flashlights........that are completely fried.
With this in mind, several months ago, I took several good flashlights (Surefire, Streamlight, Gerber Infinity,etc.) and did the home-made nested cage thing. I have lots of other good lights, so I'm not missing them, but if something DOES happen, at the very least I'll have light.
In this case,an old expression comes to mind, "In the land of the blind, the one-eyed man is king". :D:
 

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I admit I'm not one to be concerned with EMP. How can I place a cell phone call when the infrastructure's been wiped out by EMP? How can I power ANY electrical device when the infrastructure's been wiped out by EMP?

In order to make it worth my effort to shield against EMP, I'd also have to shield a power generating system against EMP. So now I'm storing batteries and solar/wind equipment in a faraday cage that I can't use until the EMP attack is over with.

You know what's impervious to EMP? Water storage, gardens, other food storage, toilet paper, etc. I'll put money and time into those things way before I worry about protecting stuff against EMP.
It isn't so much about whether you can power any electrical device when the infrastructure has been wiped out by EMP--it's more about giving yourself whatever advantages you can, post-EMP.

For instance, I have a couple of walkie-talkies in my Faraday Cage. I will, at some point, buy some more. They can be a huge force multiplier when nobody else has them. Just to be able to communicate between opposite sides of a defensive position can be tremendous. Imagine patrols being able to report back what they're seeing. I'd like to have maybe 8 of them.

My battery chargers (solar and grid/12-volt both) are in my Faraday Cage along with a number of LED flashlights. I have a very good supply of excellent rechargeable batteries (Eneloops plus Imedions). The grid/12-volt charger works off 110-volt power, plus can be run off 12 volts--from a car battery, say.

I have an Emergency Radio (Kaito KA-500) in my Faraday Cage. I want to be able to figure out what's happening, and that radio can receive Shortwave, so even if we're knocked out here, I may be able to find out what's happening from overseas sources.

All of these things--and more--can make a huge difference post-EMP. No, my cellphone won't work as the towers will be down (if the phone works at all), but that's not the point of the Faraday Cage. It's to protect items that, post-EMP, can have a huge value.
 
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I will admit this is a subject that doesnt concern me much. I would prefer a simpler time without all the electronics. ( I realize how handy some would be, just not interested )

Why not double up? You could even ground the outside one. Cover all your bases since no one is sure anyway? Even wrap your components separately in layers?
I admit I'm not one to be concerned with EMP. How can I place a cell phone call when the infrastructure's been wiped out by EMP? How can I power ANY electrical device when the infrastructure's been wiped out by EMP?

In order to make it worth my effort to shield against EMP, I'd also have to shield a power generating system against EMP. So now I'm storing batteries and solar/wind equipment in a faraday cage that I can't use until the EMP attack is over with.

You know what's impervious to EMP? Water storage, gardens, other food storage, toilet paper, etc. I'll put money and time into those things way before I worry about protecting stuff against EMP.
You don't understand the crapstorm that would happen after an EMP event. Sure it would be nice to go back to a simpler time. But you, me, and everyone else WILL NOT be going back to 1880. It will be like going back to the 1500's. There is a dwindling of people that actually know how to do stuff without electricity, as time goes forward there are even less of these people. But the kicker is even the people that know how to do stuff without electricity will not be much good because the things they used in the 1800's are not around any more. It is a BAD scenario. Add in mass pandemonium, crime, refugees, and etc, and you will be wishing you paid a little more attention to EMP's. EMP is the absolutely worst thing that can happen outside of a mass pandemic, asteroid and etc.

So while you don't worry to much about it, I'm going to "worry" about it. Then I'm going to do my best to prepare for it.
 

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You don't understand the crapstorm that would happen after an EMP event. Sure it would be nice to go back to a simpler time. But you, me, and everyone else WILL NOT be going back to 1880. It will be like going back to the 1500's. There is a dwindling of people that actually know how to do stuff without electricity, as time goes forward there are even less of these people. But the kicker is even the people that know how to do stuff without electricity will not be much good because the things they used in the 1800's are not around any more. It is a BAD scenario. Add in mass pandemonium, crime, refugees, and etc, and you will be wishing you paid a little more attention to EMP's. EMP is the absolutely worst thing that can happen outside of a mass pandemic, asteroid and etc.

So while you don't worry to much about it, I'm going to "worry" about it. Then I'm going to do my best to prepare for it.

I hate when people tell me what I understand. :) There isnt a damn thing I could do about an emp happening so Im not gonna waste my time worrying about it.
All a faraday cage will do for you is maybe give you a small interim time to use whats in it. Even charging those will be difficult unless you also have a solar charger in your cage.

I really dont know why more people dont worry about a cyber attack taking down the internet. That would pretty much stop us in our tracks in todays world also. Not near as difficult as getting and exploding a bomb 300 miles up.
 
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