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mamoo
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Discussion Starter · #1 ·
I was wondering if there is a thread for making a safe box. I saw it mentioned on the book review of "one second after"?
 

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The "Safe Box" in question would actually be a faraday cage. It is just something built to keep small electronics safe from an EMP blast.

There are a few different ways of making them to suit your needs. It all depends on how big you need go to.
 

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mamoo
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Discussion Starter · #5 ·
Okay I have to figure out what a faraday cage is now.
 

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mamoo
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Discussion Starter · #8 ·
what would be the best thing to keep in the FC? Like best batteries to keep. Would you have to put hand crank radios in there or would they work without protection?
 

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mamoo
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Discussion Starter · #10 ·
so really you have to keep crank radios in there just in case ....
Can you line a closet and make a small room into a walk in FC room.
Like they used to do in the Adirondack camps... a tin lined room to keep rodents and bugs out for the winter.
 

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YourAdministrator, eh?
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The absolute simplest faraday cage is an old microwave that you don't use anymore. It is radiation-sealed already and has a large enough "cooking area" that you can put small electronics into.

You can turn a tin-shed into a faraday cage by filling it with a few filing cabinets seperated from the walls with insulation (a couple inches would be enough). In each drawer of the filing cabinets, you can place all kinds of small electronics (auto-computers, alternators, ignition-systems) that would be protected from an EMP-blast.

You can build another faraday cage inside your house by making sure that there are no power-lines in the walls near the special room. Line the outside of the room with thin-guage aluminum (20 guage would be good), cover with drywall and then line the inside with another layer of thin-guage aluminum. Inside the room have it lit with battery-operated lights - just replace the batteries regularly or you could use a couple of spiral-core gel-cell batteries and swap them out with each other and use a solar-panel to keep them topped up when outside of the faraday room.

There is lots of information on the 'net about a faraday cage, but, to get you started: Faraday cage - Wikipedia, the free encyclopedia

:google:
 

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so really you have to keep crank radios in there just in case ....
Can you line a closet and make a small room into a walk in FC room.
Like they used to do in the Adirondack camps... a tin lined room to keep rodents and bugs out for the winter.
Sure you can build a Faraday cage just about anywhere and out of just about any metal, metal screening, hardware cloth, even small chicken wire, as long as you follow the guidelines, encased( top,bottom,& sides) outer cage grounded with the shortest ground wire(path of least resistance) and a inner core insulated from the outer grounded one. You do not want to create a electrical path between the two, the two being in close proximity may even create a path, thus the insulation. Putting a radio in a large ammo can that has been lined with foam and the radio wrapped in alternating layers of thinner foam and aluminum foil can resist EMP. AS long as the metal does not touch metal.
Here's a bunch of photos... http://images.google.com/images?q=f...esult_group&ct=title&resnum=4&ved=0CC8QsAQwAw
 

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mamoo
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Discussion Starter · #13 ·
That sounds easy enough.... not like I read on wickapidia.
 

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Good tip on the microwave. I didn't know that.

Regarding radios, tv's, etc. If they have an external antenna the farady cage won't help because the EMP will use the antenna as a route to the radio/tv. If you want to use something with an antenna the best thing is to disconnect and ground the antenna any time you aren't using it. We do this with our CB and Ham radios when lightning storms move in or when we will be gone a few days.
 

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YourAdministrator, eh?
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I found this on another site

UnitedStatesAction.com said:
The reality of protecting all electronic equipment against EMP from a nuclear explosion over our shores is becoming imminent. We now live in perilous times.

The information to follow on building "Faraday cages" is timely indeed. A single atmospheric nuclear detonation releases enough electromagnetic pulse (EMP) to equal 100,000 volts per square centimeter on the ground. A single detonation 200 to 400 miles over the center of the continental United States would fry every unprotected computer chip from coast to coast, and from the middle of Canada to the middle of Mexico. And we are now into Solar Cycle 23, with solar flares common and expected to continue until the first of next year. CME's are capable of extreme damage to modern computerized equipment! Sure, we have our windup BayGen radio's and spare lap top computers, but unless electronic equipment is protected from an electromagnetic pulse, they will be fried!

When Einstein and the others first refined and purified uranium, they took time off and studied its properties. That is when they discovered the "rays" that were harmful, as well as the phase transformations. In the course of their work, one of the scientists discovered that simply covering an object with a grounded copper mesh would stop virtually all electromagnetic radiation, whether proton or neutron. Obviously, they had to protect their monitoring equipment! Thus was born the "Faraday cage."

The copper mesh, like 1 inch chicken wire, worked well in large uses, like covering buildings, and it is still in use today: FEMA headquarters buildings are dome-shaped earth-bermed structures, and under the earth is a copper mesh that extends out from the base and is secured by grounding rods.

As an Electro Magnetic Pulse (EMP) travels to earth, whether from a Coronal Mass Ejection (CME) or a nuclear detonation in the atmosphere, it hits and runs along electrical power lines as well, building up voltage and amperage, which is what happened during the last solar storm a dozen years ago, blowing out transformers and leaving 6 million people in eastern Canada without power for weeks.

To prevent that problem, if you have a hard-wired generator, the wiring from the generator to the house should run in conduit that is grounded. The generator itself can have the frame grounded for added insurance, but that ground wire MUST be insulated and run to a different ground rod well away from the ground rod for building and conduit!

With radio's and smaller appliances, a Faraday cage can be built by using two cardboard boxes: one should fit tightly inside the other, and the item to be covered should itself fit reasonably well inside the smaller box. That is about the most work involved--finding the right size boxes! The outer box is then covered with aluminum foil or Mylar, as from a cheap "space blanket." A grounding wire is then taped to the foil. I then cover the foil with black 6 mil plastic, taped securely in place, to protect the foil from ripping. At the end of the ground wire I attach a cheap small alligator clip from Radio Shack. The item to be protected is placed inside the inner box, which acts as insulation from the outer box, and any EMP hitting the foil and is bled away by the ground wire.

Some medium sized electrical equipment can also easily fit into boxes covered with foil for EMP protection. My laptop computer, for example, fits easily into a Faraday box made from a box that held reams of paper: the entire lid is removable, allowing easy access to the laptop in its case, but is safely stored when not in use.

For larger items which cannot be boxed, such as living room TV sets, etc, I tape a Mylar space blanket to a piece of 6 mil black plastic sheet, using double-sticky tape every foot or so to make sure the Mylar stays in place (it is slippery). I leave a 2 inch edge of black plastic showing all around the space blanket, and while taping down the edges I put on a short lead of ground wire. When it appears that EMP or CME's are on the way, the blanket can be draped over the appliance, the alligator clip attached to a small, unobtrusive ground wire behind the cabinet, and any electromagnetic radiation will be diverted to the ground wire. Very cheap, simple, and once done, items can be "draped" for protection very quickly indeed. And the plastic blankets fold up neatly for storage, ready for use when needed.

The time to build Faraday cages or blankets is NOW, as when they are actually needed it will be far too late. Each box should be labeled on the ends and the top for the exact appliance they were built for, to eliminate any confusion when they must be protected in a hurry. Any electrical appliances not in use should be stored in the Faraday cage, where they will be kept clean, neat, in a known location, and protected against any sudden EMP surge.

EMP AND FARADAY CAGES
You don't need anything really fancy for a faraday cage - even a couple of nested cardboard boxes will do the trick ..
 

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mamoo
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Discussion Starter · #17 ·
I thought you would have to keep everything in there all the time unless in use. You don't really know when an EMP hits until it has hit.... right?? How long would you have to put stuff in? You might even want to have more than one of what ever you want. And if there is a EMP computers wouldn't work anyway. The satellites would be knocked out also right? We could keep a cage around our generator too. It is portable. But it is loud when on and people would hear it. We have 10 acres and when we had the storm this winter everything was so quiet you could hear the gen real well.
 

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YourAdministrator, eh?
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There isn't anything in a generator to worry about for EMP - everything in them should be fine. You can run your genny-for-stealth (see our electrical section for a thread with that title).

Do not expect to be able to save everything from an EMP-burst, but, you can try to minimize your losses. When you are finished using your laptop, put it into its case, put the case into a filing cabinet and make sure that it is always closed. Have a portable DVD-player in a case and put it into another drawer in the filing cabinet.

Setup an RV-based solar system with small portable inverters (under 1000 watt) and keep the inverters in another faraday cage. When you need them, plug into the battery system (EMP will not harm solar charging systems unless they are grid-tied) and run 110volt.

The fact that you are on 10 acres tells me that you would be better off than 90% of the city dwellers - EMP would be less likely to harm you unless you have a major power transmission line running near your yard.
 

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mamoo
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Discussion Starter · #19 ·
A portable dvd player !!!! Thats a great idea! When the power was out our gen was hooked up to certain outlets and the tv was one of them. Believe it or not it was very comforting ..... as long as we didn't put on a disaster movie.
I will definitely look into genny-for-stealth... thank you.
How far away is far enough for major power transmission lines? I don't think we are too near but I'll ask my Hubby.
About 15 years ago they wanted to put a cell phone tower on out property and I said no but they offered to give us free cell phones and I said no nothing is for free. I was not going against my Husband either at the time he thought computers and cell phones were the devil....
My Husband has an inverter in his truck .... is that what you are talking about?
Would EMP effect those?
 

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YourAdministrator, eh?
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There is alot of information about EMP and the effect it has on electronics - so much that it might be easier to send you off to the many technical based websites that have that information easily accessible if you want to understand the technical nature of EMP.

The simplified version of an EMP-burst: unless an EMP-burst is directly overhead (within visible distance to each horizon), it will not affect you without being able to travel along power lines (think of the power lines as part of an antenna that transmits radio signal into a receiver). Unless you have a pacemaker installed, the EMP-burst will not affect your physical body.

The burst will "spark" towards anything that it can from the power lines and anything within direct contact to those lines can be fried, and anything within a certain distance of those lines can be fried if they are not in a faraday cage. You house is directly tied to those lines, so, your house can help spread the EMP-burst to anything inside your house that is electronic inside (TV, VCR, DVD, Computer, Phone) but it should not harm heavy-duty items like a furnace motor unless it was running at the time of burst - then your guess would be as good as mine.

Meaning - if you have a steel-quonset on your yard and it is nothing more than a shed without power and a vehicle is inside it, the EMP-burst will "flow" down the outside of the quonset and into the ground, missing the vehicle parked inside it.

Now, if that same vehicle is parked outside within a mile of an overhead power line, the EMP-burst might take out the computer in the vehicle making it inoperable. If the vehicle is driving and an EMP-burst happens and the vehicle happens to be on a road with an overhead power line within sight, the burst could again take out the computer and make it inoperable.

The vehicle could stall and not start again.

You have seen thousands of electrical bursts in your life (think thunderstorm with lightning) and in general they don't harm much, but when they do, they do lots of damage. EMP is similar in nature, only significantly more powerful with a greater range of electrical destruction than with summer lightning storms.
 
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