Faraday Cage

reply to post by thehoneycomb


I worked on secure Hardware such as PC's for many manufacturers. The cover of your PC is a simple Faraday cage.

The cover is grounded by a simple Fetron mounted to the back of the connection to your power cord.
It is inside your PC;s power supply.
It provides a path to ground from

#1 - incoming spikes from utility power
#2-; external static and RF blocked by the cadge.
#3- RF from internal components.

The only difference between the (secure) military grade cover and a normal cover is that the military grade has about 30 more screws. The difference in the power supplies although is reflected by the cost and grade of the Fetron protecting the power supply. A cheep Fetron is 3 dollars US and expensive one could be close to 100 dollars US.

Main Frames and large data storage of the 80's are huge and are basically trash. The covers are almost all largely just faraday cages'.

What are you trying to accomplish with your cage?

My specialty was just in this sort of thing.

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Watcher

reply to post by n120by60w


Well me I have a macbook, so I hear I am better off. It has the aluminum cover.

But I would like to spare simple things too, like flashlights, iPod etc.

reply to post by thehoneycomb


We all build what we have to build when it has to be built. I've sold the house since, but it was a very nice recording studio, 5 pane sound glass, a 78" high 19" rack fully loaded, 24 track 4 buss mixing plus 16 track hard drive recording, Yamaha YD drum kit in the bar with the triggers going back to an Alesis DM-5, 5 servers on shelves, etc. I was pretty nuts about my music since I play keyboard and guitar. It was a hobby that turned into a business for my wife, we ended up getting licensed by 4 major record labels for production. It's a few years ago now but I still have all the instruments and the recording equipment and I am in the middle of putting another band together to play for "fun."

The interesting thing about Faraday cages in rooms is you always have lights and receptables. So, just as an aside, you can make metal boxes to shield your outlets (which I did) but the lights I ran a DC system from another room at 12vdc and set up halogen lights. It depends on whether you want shielding for testing or shielding against intrusive government scanning on how you set up your electrics. If you just want to build a protective box of a specific size for "something" in the event of EMP, you can buy plastic coated foam, it's very stable and strong. Glue the box together, then coat the inside and the outside with foil, make sure when it closes there are no holes. Ground the foil to a good earth ground like a metal drainpipe or waterpipe and you're good to go.

Cheers - Dave

reply to post by bobs_uruncle


I am a musician, I can play the keys and guitar and bass and a little drums and violin too. I'd like to keep all that stuff, but logistically it doesnt seem reasonable if it happened say tomorrow. I am interested though in the knowledge and experience you may have in that realm. I can't convince the wife to move to the country so I might have to defend the castle for a few, but by then she will be convinced. So then well be on foot.

reply to post by mileysubet


Yeah dead rooms are quite a neat thing. They sure tell you real fast whether you have Tinnitus or not LOL. I've been in a few in the universities (since my main work is in engineering and physics) in large EMF and Sound chambers (anechoic chambers). Generally though, EMF chambers are not well sound insulated and sound chambers are not well EMF insulated, so when you do one both ways, it's bloody magic ;-)

Cheers - Dave

reply to post by thehoneycomb


I have had equipment fried that was installed with no expense consideration limit for grounding and security.
The equipment I spoke of was fried during a real EMP. I found that a real EMP actually causes a 30k or more ground spike that will fry stuff not even turned on during the event if it is connected to a proper ground.


If an EMP is of a has a natural cause (Solar), or man made one then the only thing still working afterwords might be power. But most likely there will be no one but some old tube radio gear still working else where and it won't have power. So your computer will have no use that for you unless it is a stand alone. The network cloud will be gone.

Most, if not all communications will be down.

To get the effect you desire the actual cage might be better left ungrounded.
Equipment unplugged from any power source.
There should be no external Annetta connected at the time of the burst.
I would think this might also work if the Earths field were to reverse. (NS)

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reply to post by thehoneycomb


Well if you need any information on anything like Faraday Cages or engineering in general, fire away, just send me a private message just to keep it out of the forums. On the music side, I can tell you how to organize licenses and through the right people, I know a lot of the A/R in places like UMPG, Sony and others. I've done track work for artists you would recognize. I run a series of networks for my recording equipment, so I have WC, ADAT systems, MIDI, etc. with separate controllers. The wiring isn't that hard it's just annoying. But I do love my sound ;-) The main monitor signals come off the board (rather than the computers) but they go through a quad mdx-4600 and then hit a dbx-bx3 driving infinity and dalquist monitor speakers, I think it's about 1200 watts, 4 channels (not incredible power but the old 80's high end technology). In the studio I had the speakers mounted in the wall corners facing each other about 12 feet apart and the sound insulation was so good you could crank it up to about 500 watts a side and you could still have a normal conversation, at least until you stuck your head in the middle of the room LOL.

As I said, this was just a hobby at first, but the wife wanted to make a business of it, so I let her. If you want to know more about EMF shielding using destructive interference, I can tell you about that as well since I just patented a device.

reply to post by n120by60w


Interesting.. would like to hear more about that.

reply to post by bobs_uruncle


Cool. I have about a hundred tracks that need to be redone. But anyhow I've been busy with a lot of other stuff so unfortunately my music has taken up a dusty shelf for now. Would love to get back into it though and maybe I will need your advice in the future.

So I apologize in advance for sounding ignorant here.... but I did not realize that the mechanisms that make a flashlight work are complicated enough to be at risk from an EMP? I thought it was computer chips and whatnot that are at risk from EMP.... Can someone elaborate on that a little, in a very dumbed down, Barney-style sort of way?

reply to post by MojaveBurning


Invest in some old school flashlights while you can still find them. I've been switching to super bright LED's for years and now I wish I still had my old and simple ones lying around. Amazing to think of how microprocessors have entered so many aspects of our once simple lives...

OR
Stock up on oil/kerosene lamps, candles and extra fuel and wicks. That has been my latest mission... I've got 4 lamps and plenty of fuel and wicks to last for quite a while should the need ever arise...

Keeping your flashlights safe really is not worth the time to build a faraday cage, You would have to stock up on many many batteries to even make it worth your cost. I guess you could always use a cheap usb solar charger, I would be more worried about keeping my: Solar, PMA's (Permanent Magnetic Alternators) for wind charging, Inverters AC-DC or DC-AC, Charge controllers, soleniods, capasitors, anything electronic that could be torn down and reused for making other Energy forming items. Yes grounding your faraday cage is very important, drive a 3/4" copper rod or metal if you dont have copper into the gound at least 3 - 6 ft deep connect a thick gauged wire to that rod and run it back to your cage,I would keep plenty of distance from your ground to your cage. otherwise your cage will be a toaster.

I am building a 6x6 ft cage next month to hold all my electrical back up gear.
will be a fun project..

I use a tool box with the front drawers covered by aluminum mesh held to the box with metallic tape. I have extra parts for my van, an old laptop, a "jump box", an inverter, a battery charger and some rechargeable batteries, some small solar panels to charge the "jump box", a night vision monocular, a crank flashlight/radio, and some other stuff. I believe it works since my cell phone doesn't work when called while in the box. The tool box is a craftsman style bottom box with 6 drawers and a compartment in the bottom roughly the size of the inside of a newspaper box you might see outside a convenience store.

Appologies if already answered but not read the entire thread. It is important to remember that a Faraday is only a Faraday cage if it is properly grounded, this means that it is difficult to carry around without breaking its connection with ground. If it is not grounded it is just a metal box. The best material to use in a Farady cage is copper or gold even if your loaded enough but any conducting metal will work. It only has to be a cage it doesn't actually have to be a box but do not make the mesh size too big. An old PC case is actally a faraday cage, providing you keep it plugged in and the box is earthed correctly.

reply to post by michael1983l

Good point. I forgot to mention that I have three ground wires attached to my box. One ultimately grounds in my breaker panel at the ground buss. One grounds to my water pipes. The last grounds to a 4 foot long metal post driven into the ground. 12 gauge copper wire is used for all three.

Originally posted by MojaveBurning
So I apologize in advance for sounding ignorant here.... but I did not realize that the mechanisms that make a flashlight work are complicated enough to be at risk from an EMP? I thought it was computer chips and whatnot that are at risk from EMP.... Can someone elaborate on that a little, in a very dumbed down, Barney-style sort of way?

An EMP produced by an air blast Nuclear Bomb effectivly creates a highly charged magnetic radiation pulse that will propogate through the air in all directions. The energy in this charge is so high that it is desperate to disipate and does so by disipating onto anything conductive. All electrical equipment that isn't sheilded will be instantly overloaded with energy thus blowing the componants inside. All that is likely to go in a flash light is the filament in the bulb.

Originally posted by thehoneycomb
Also before I forget there were a few other things I wanted to ask. Maybe someone knows the answers. In the event of an EMP, how long would you have say it happened 30 miles away to get your gear into a faraday cage? How long should you leave it in there?

Would all cars and electronics be useless? How would you go about restoring equipment after an EMP? Is it essentially the same as taking a magnet to a hard drive or a cassette tape?

I am not sure anyone answered your question on how long you had if the EMP was 30 miles away...

The EMP travels at relativistic speeds (close to 90% the speed of light) so I think you would have (and not checking my math here). 0.00018/sec give or take...

You would not have enough time, this is not an act after event it is an event you plan before for the after effects.

What concerns me about "amateur" Faraday Enclosures is that we might miss an important or practical element of a good enclosure that may lead to signals leaking in or out. If EMP is your only concern then it is possible to construct a good simple Faraday Enclosure, but if you wish to reside inside the enclosure or if you wish to block out surveillance signals like those belonging to listening, watching, or computer monitoring devices then you may need to consider a more professional enclosure.

Professional Faraday Enclosures

Good informative website:

Faraday Cages.com

They have solutions for different applications, the application of most interest to the private party is the following:

Private Party Solutions

They have a "Faraday Tent" you can buy that will block out a range of signals both electrical and magnetic.

Faraday Tent

reply to post by abeverage


An EMP travels at 100% of the Speed of light, it is effectivly RF radiation which also travels at the speed of light.