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.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?
Do not ground your Faraday Cage.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.
There are two reasons people want a microwave to work as a Faraday Cage (but it doesn't):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.
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.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
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?
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.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.
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?
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.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.