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Faraday cages - EMP weapons or Massive CME's.

  There are now a lot of people without power on the east coast that may have wished they had prepared more. Have heard a lot about Faraday cages lately. What exactly are they? If a EMP weapon or a large CME hits us, we are toast. It could take many months maybe a year to get the grid back up. What are these devices & do they really protect electronoics? How do you make them? From what I understand they are easy. Do I stick my handheld Yaesu  Ham radio under a large metal bowl or what? If it is a EMP weapon shot over the USA,  Well ....., God help those that set it off.


Modified by Joseph Porcelli - GovDelivery, Inc. (1 year ago)

Dear Re

Pick up an old microwave @ a garage sale cheap.  Take the male plug off, twist wires together and ground it someplace different that your electrical service is grounded.  Excellent Faraday Cage.  IF there is a massive CME the electrical system will fry, that is why the separate ground.  Good luck.

Hungry Fred

Jim Nicol 1 year ago   Reply

Try these links for EMP info:

Hope this helps

Willie Coleman 1 year ago   Reply

HowStuffWorks "How Faraday Cages Work" Jul 20, 2011 – Faraday cages shield their contents from static electric fields. Learn howFaraday cages work and how they are used for a variety of purposes.
Sam Ripley 1 year ago   Reply

A faraday cage is an enclosure made of a conductive material, usualy a fine metal mesh. The basic idea is that static charges and electromagnetic radiation are distributed around the surface area of the faraday cage instead of being conducted inside the enclosure. Microwave appliances, for example, are inside-out faraday cages that keep electromagnetic radiation from escaping rather than getting in.

If you wish to take it upon yourself to build a faraday cage for your radio, I'm sure you could find some plans on the internet. However, this would by and large be more useful for protecting it against something like a lightning strike. I would suggest that if you want to be prepared for being without power, go with more typical preparedness measures like having available food, water, sanitation and heat. Not to discourage a cool DIY project like building a faraday cage, I'm all for it really, but protecting against an EMP strike that will disable the grid as opposed to a physical disruption like an earthquake or major storm are of a higher concern to me.

Jonathan Houg 1 year ago   Reply

Hi Bonnie. For expediency, a metal garbage can with lid would work as long lid is tight. A microwave oven will also work. Otherwise, you would have to cage anything else by utilizing wire mesh out of metal and placing your device inside using a wood frame. As far as a CME, this is highly possible, matter of fact, the sun has been spiking this week, here is one website you can go to for info: Also, a weapon used against the United States is possible as well, let us hope that those Aegis Cruisers are paying attention. As far as being prepared for anything really serious, not many people are nor is apparently local, state or even federal, look at what the storm has caused in several states and the situation with the power. Here in Kentucky where I am, we have had several days with the temp at the spot where I am hovering around 103-105. With no power, this is an uncomfortable situation. I work hard to get people to just simply take basic precautions, but for some reason their seems to be something in their brains wired incorrectly, no one seems to want to do so. I can tell you what works from experience. a whole home genset which operates off of propane, and have a 500 gallon tank. 6-8 240 watt solar panels and inverter(s) along with several batteries, don't waste your time and money on the single battery cart,  single panel sold as a way to get your power going, this is miss-leading. Once the power is out, you will quickly discover how quickly a battery goes dead and you have to have a way to quickly re-charge the battery(s). Also, all of these items are subject to failure from CME flare event (EMP). Aluminum foil would also probably work. The only way to really know is to try it on a small scale and use an O-Scope to verify no leakage. Also as you can very well see, the storm events are really minor compared to other things which can take place (localized) and those areas are struggling so I am not sure what happened to the idea of being ready, infrastructure preparations obviously are still not in place. If we were to have an extreme event on a large scale, with resources overwhelmed, well you get the picture I am trying to paint. , I hope some of this information helps you out and if you would like some more information I believe FEMA has more info throughout their website, and actually the CDC also has information.. Also, has some info which I have posted (my website) on page two, but is not EMP specific, perhaps I need to add this information.


What measures have you put into place to overcome a natural EMP event? This week, the Sun has exhibited spikes which at anytime could release an X-Class flare.

  • Hardened Electronics
  • Faraday Cage
  • Long Term Backup Power Supply
  • Reserve Batteries
  • Solar Panels
  • Wind Power

This poll closed on Jul 23rd 2012

         Thanks for all the information! This is a great group! We might have some warning from those that monitor space weather about a CME, however a EMP weapon, ... no real warning. Thinking about it a EMP attack could  be a lot worse than a CME. Iran is a real threat. Lets hope they never try it, we would get fried, however they would end up looking like a hole in the ground with a shiny glass bottomless pit after we finished with them. Stupid move on their part, however terrorists are suicidal. 

Lanelle Devlin 1 year ago   Reply

You can make your own.  We have an old, old truck but it still uses an electronic ignition.  What we did is buy a second or back-up drop in if there is an EMP.  We simply took ours and wrapped it multiple times (multiple layers) of heavy duty aluminum foil.

If there is an EMP type of event I believe covering with a bowl will be too late.  We have back-ups that are already protected.

If you wrap in foil or other metal containers then acquire an old freezer (free on Craigs List or local Freecycle) bury it in ground and put in that for additional protection.  Plus you will know right where to go when you need those items.

that's my $0.02 worth.

I also teach classes on emergency preparedness, food storage and frugal off-grid living.


Roy Dugger 1 year ago   Reply

As to what a Faraday Cage is:  simply a box made of/or lined with a material that conducts electricity. Check out Wikipedia and How Things Work for more info. An Electromagnetic Pulse could also be created by a very large solar storm, so not just a man made threat

What would work for you: Any metal container will work.  If you have sensitive electronics that you want to protect, you can use old metal ammo cans.  If you have a few minutes to prepare, you can use your refrigerator or your microwave oven.  Depending on frequency, a chicken coop or dog kennel made of wire screen could work as well.

Jim Nicol 1 year ago   Reply

check out these sites for more info.

Richard Perry 1 year ago   Reply

Many years ago (1980's) I worked inside a Faraday cage.  It was required to screen-out randon RF noise while accomplishing precision output attunator calibration on various  high-frequency (10 to 24 Ghz) signal generators.  Once the door was closed and secured, NOTHING penetrated the cage (it was double-screen built with pure copper wire mesh, 8' by 8' by 8' high).  The electrical power was run through a very narrow acceptance range band-pass filter to preserve the noise isolation.