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MOlivo
11-28-2007, 04:39 PM
Some electrical equipment is innately EMP-resistant. This includes
large electric motors, vacuum tube equipment, electrical generators, trans-
formers, relays, and the like. These might even survive a massive surge of EMP
and would likely to survive if a few of the above precautions were taking in
their design and deployment.

At the other end of the scale of EMP resistance are some really sensitive
electrical parts. These include IC circuits, microwave transistors, and Field
Effect Transistors (FET's). If you have electrical equipment with such com-
ponents, it must be very well protected if it is to survive EMP.

One "survival system" for such sensitive equipment is the Faraday box.

A Faraday box is simply a metal box designed to divert and soak up the
EMP. If the object placed in the box is insulated from the inside surface of
the box, it will not be effected by the EMP traveling around the outside metal
surface of the box. The Faraday box simple and cheap and often provides more
protection to electrical components than "hardening" through circuit designs
which can't be (or haven't been) adequately tested.

Many containers are suitable for make-shift Faraday boxes: cake boxes,
ammunition containers, metal filing cabinets, etc., etc., can all be used.
Despite what you may have read or heard, these boxes do NOT have to be air-
tight due to the long wave length of EMP; boxes can be made of wire screen or
other porous metal.

The only two requirements for protection with a Faraday box are: (1) the
equipment inside the box does NOT touch the metal container (plastic, wadded
paper, or cardboard can all be used to insulate it from the metal) and (2) the
metal shield is continuous without any gaps between pieces or extra-large holes
in it.

Grounding a Faraday box is NOT necessary and in some cases actually may be
less than ideal. While EMP and lightning aren't the "same animal", a good
example of how lack of grounding is a plus can be seen with some types of
lightning strikes. Take, for example, a lightning strike on a flying air-
plane. The strike doesn't fry the plane's occupants because the metal shell of
the plane is a Faraday box of sorts. Even though the plane, high over the
earth, isn't grounded it will sustain little damage.

In this case, much the same is true of small Faraday cages and EMP.
Consequently, storage of equipment in Faraday boxes on wooden shelves or the
like does NOT require that everything be grounded. (One note: theoretically
non-grounded boxes might hold a slight charge of electricity; take some time
and care before handling ungrounded boxes following a nuclear attack.)

The thickness of the metal shield around the Faraday box isn't of much
concern, either. This makes it possible to build protection "on the cheap" by
simply using the cardboard packing box that equipment comes in along with
aluminum foil. Just wrap the box with the aluminum foil (other metal foil or
metal screen will also work); tape the foil in place and you're done. Provided
it is kept dry, the cardboard will insulate the gear inside it from the foil;
placing the foil-wrapped box inside a larger cardboard box is also wise to be
sure the foil isn't accidentally ripped anywhere. The result is an "instant"
Faraday box with your equipment safely stored inside, ready for use following a
nuclear war.

Copper or aluminum foil can help you insulate a whole room from EMP
as well. Just paper the wall, ceiling and floor with metal foil. Ideally the
floor is then covered with a false floor of wood or with heavy carpeting to
insulate everything and everyone inside from the shield (and EMP). The only
catch to this is that care must be taken NOT to allow electrical wiring
connections to pierce the foil shield (i.e., no AC powered equipment or radio
antennas can come into the room from outside). Care must also be taken that
the door is covered with foil AND electrically connected to the shield with a
wire and screws or some similar set up.


to read the whole article click the link below
http://www.textfiles.com/survival/emp.pro


--------------------------------------------------------------------------------

The author of this article, Duncan Long, is well-known as the writer of many
gun, self-sufficiency, and survival books. His firearms books are listed
(along with other interesting books) in a free catalog available from Paladin
Press, P. O. Box 1307, Boulder, CO 80306 (303) 443-7250. Long's NUCLEAR WAR
SURVIVAL is available for $14 from Long Survival Publications, 115 Riverview
Dr., Wamego, KS 66547. Long has also recently had a post-nuclear war sci-fi
book, ANTI-GRAV UNLIMITED released from Avon Books

ZombieHunter_EKY
12-03-2007, 12:16 PM
At what year do vehicles not have the electronics that a EMP can harm.

chicom
12-03-2007, 12:47 PM
At what year do vehicles not have the electronics that a EMP can harm.


I think emp resistant were stopped being made in the early 80's. Maybe 82-83 timeperiod. I believe any vehicle made from the 70's and prior will be good to go.

ExOp:345
03-02-2008, 10:38 PM
it would be a nice idea to throw a laptop with all your survival information in one of these, incase an EMP hits like in "Lights Out", so that you have all of it if you ever need it.

Christian for Israel
03-02-2008, 11:43 PM
1974 was the year the first electronic ignition came out...of course simply converting a regular gas burner (carburated) back to a points and condenser type ignition would be easier than finding a running antique imho.

soberups
03-03-2008, 12:22 AM
I have heard that the easiest way to make a Faraday box is to simply put whatever you want to protect inside of a microwave oven....the big old ones can often be scrounged from a landfill, or bought for $5 at a garage sale. They are designed to prevent microwave radiation from getting OUT, so they would naturally also keep it from getting IN.
I have also heard that an automobile acts as a Faraday cage to some extent...the electrical components are encased inside the metal shell of the car, and the shell itself is not actually grounded to earth since the vehicle is sitting on rubber tires which act as insulators. I dont know how true this is.
Would an EMP damage an electronic component that was not turned "on" when the pulse occured?

site59
03-03-2008, 07:57 AM
? for the thread, would static bags work for emp?
Thease are the type of bags electronic equipment come in.

Christian for Israel
03-03-2008, 09:38 AM
the principles of a faraday cage are simple, metal blocks EM radiation (radio waves are an example of EM radiation). the reason they are called 'cages' instead of 'boxes' is that you don't need solid metal to block the EM radiation, a mesh will work. the thing is, the size of the openings in the mesh are important. electro-magnetic radiation travels in waves. the wave length (the distance from one wave peak to the next) determines what the wave can pass through. EM wave lengths are fairly large, about half an inch up to several inches long. for the wave to get through there has to be an opening larger than the length of the wave. for example, standard chicken wire, with 1 inch openings, will stop many of the longer wave lengths, but will allow some of the shorter ones through.

microwave cases are indeed faraday cages. even the window is covered (look carefully at the window and you will notice it is covered by a metal mesh with very small holes in it). it's not the glass in the window that holds back the radiation but the mesh. a cage built with a 1/4" mesh will stop the EM pulse and protect equipment, but the coverage must be complete (EM radiation strikes all sides at the same time). the floor, walls and ceilings must be covered completely and any opening (door) must be closed and sealed for it to work. it is for this reason that cars do NOT provide protection as all it takes is one opening larger than the wave length for the barrier to be breached and the electronic equipment to be destroyed. cars have many openings that would have to be covered.

what's more, any wire 30 or more inches long leading from the outside to equipment within the cage will conduct the pulse right to the device, zapping it. car computers have many wires attached that lead all over the vehicle. isolating and shielding all of them would be a daunting task and missing just one would be disastrous. to show how ineffective cars are at stopping EMP, try using your cell phone while sitting in one. the phone uses EM (radio) waves to send and receive signals. if the signal is blocked there's a good chance the vehicle is safe. if you can get a call through it definately is not. that in fact is the best test for any cage...see if a radio or cell phone will work inside it. if not, but it does work outside, the cage is probably effective.

static and other mylar bags will work if they don't have any holes or tears in them, but to be truely effective the device must be insulated from the sides of the cage. your best bet would be to wrap them in bubble wrap prior to placing them in the bag, then sealing it up. this also goes for regular metal containers.

alpmco
03-03-2008, 11:17 AM
Radios and cell phones don't work in my office. I have to go stand by the window to get a minimal signal but outside I have full signal. There is some sort of metallic film sandwiched in the glass to reflect the sunlight. The walls have steel studs.
But ... I can receive some FM Broadcast stations so it's probably far from EMP proof.

Christian for Israel
03-03-2008, 07:41 PM
that's the thing alp, failure to receive signals doesn't ensure protection, it just sufggests it. but getting a signal ensures there is NO protection. EMP will be a lot stronger than radio waves so simply blocking a radio signal doesn't guarrantee a strong EMP will be blocking as well.

ExOp:345
03-03-2008, 10:46 PM
What about those big metal trashcans? i bet those would work nicely...

EDIT:NOT dumpsters, rather the trash-can shaped ones.

Christian for Israel
03-03-2008, 11:50 PM
actually, galvanized trash cans make excellent faraday cages, as long as the lid fits tight. the best thing to do is buy a new one and line the bottom and sides with foam sheeting. place your items inside and firmly press the lid into place. finally, screw the lid down using 1" self tapping sheet metal screws every few inches. this assures the lid doesn't come loose if bumped.

alpmco
03-04-2008, 10:58 AM
I think I'll keep my eyes open for a big microwave oven. If I pull the magnatron and cover the opening with metal it will lighten the weight.
Or maybe I'd be better off to weld up a big steel box ... it's the door details that I'm leery of. I'd like to have easy access so screwing a lid on and of is not an option. Microwave oven = easy access.

alpmco
03-04-2008, 11:10 AM
Oh ... BO Vehicle link:
http://www.alpharubicon.com/bovstuff/bovstuff.htm

Christian for Israel
03-04-2008, 11:45 PM
just order a 20mm ammo can, they work great.

ZombieHunter_EKY
03-05-2008, 08:44 AM
Just make sure they are not the plastic 20MM cases. So any type of Ammo can will work as long as the rubber gasket is in place CFI?

Christian for Israel
03-05-2008, 09:24 AM
the gasket shouldn't hurt anything as there is metal all around it. if you're concerned though you could cover it with a thin strip of aluminum foil before closing the box.

mitunnelrat
03-05-2008, 10:24 AM
Something interesting I've run across while searching other topics has been the development of faraday clothing and bags. The clothing maker is lining pockets and he and his associates have self-injected RFID chips to test the effectiveness of their pockets against unauthorized access to the chips, all in preparation of that widespread possibility in the future.

In another article I was reading on gangs and organized crime in the United States. They (criminals) were using "special bags" to defeat anti-theft devices in stores they were stealing OTC cold medications from. No... I'm not condoning or suggesting theft as one of our uses, but a faraday bag may be just the thing to protect a GPS unit (for the navigationally-challenged) and assorted other items you may deem vital to daily life (laptop, pda, etc.)

Christian for Israel
03-05-2008, 09:08 PM
i keep all my cards ( drivers license, visa card, etc) in an altoids tin so embedded chips can't give my location away when i walk by a transceiver (like when entering wally world). one card i carry is an RFID entry badge for the local mine (where i deliver water several times a week). with the tin closed the reader doesn't 'see' it, but with it open, even with the badge buried under all my other cards, it reads it just fine.