Faraday cage

[Hamradioop]

it all depends on the size of the mesh, ie what part of a wavelength at what frequency it will allow to pass. think wave guide.

[Arzosah]

From my research (not all of which I understand completely, I confess) grounding seems to be a bit of a red herring: Hamradioop's definition from wiki doesn't include it, and nor do any of the discussions I've been reading about it.

[ForgeCorvus]

Ultimate demonstration of the Faraday principal
https://youtu.be/fchoI5vpBjE

[90.]

OK. here goes.. hamradiroop is correct about the size of the holes.
A Faraday cage - or wire suit does not need an insulating liner but it does need an earth to allow the the voltage or EMF to dissipate, read bleed to earth.

Without an earth connection the cage would be at the same voltage as the source and stay at it until is dissipated, same with EMF generated by an EMP, if you the touched the cage YOU would ground it if not directly to earth then by providing a change of potential eg you being a lower voltage than it.... ouch..! think static shock.

The after effect of an EMP will not only be a lack of working electronics - It will be a real bad hair day for anyone not bald or at least a crew cut..

To be effective a Faraday cage MUST be earthed, a good example is an anti static bag for holding PCBs this is a small scale Faraday cage TIP ... store your goodies in these then put them on a nice metal shelf standing on the floor.

These bags stay at the potential that was generated by carrying them around(static), once they are grounded by being put down or handed to someone at a different potential(voltage) they dissipate the static held on the outside of the bag thus protecting the contents.

regards all
90.

[sniper 55]

Wont the EMP knock out most cars electronic ignition systems?

[Hamradioop]

Wont the EMP knock out most cars electronic ignition systems?

That is an unknown, manufacturers are known to have tested various models on an emp range but have not released the results..

have a look at this discussion thread http://www.thesurvivalistblog.net/quest ... -vehicles/

extract from http://www.futurescience.com/emp/vehicles.html

the U.S. EMP Commission tested a number of cars and trucks at the L-3 facility in Colorado. Although this was the most comprehensive set of tests on vehicles that has been done, those tests were very poorly done because the Commission was financially responsible for the vehicles, but did not have the funding to pay for any of the vehicles they tested. The vehicles were borrowed from other government agencies (most vehicles came from the Department of Defense); and the vehicles had to be returned to those lending agencies in good condition.

Those vehicles were tested up to the level that some sort of upset occurred, then further testing was stopped on that vehicle. In most cases, after the initial upset occurred, the vehicle could be restarted. In most of the remaining cases where the vehicle could not be immediately restarted, a latch-up had occurred in the electronics, and the battery could be momentarily disconnected to "re-boot" the electronics, and the vehicle could then be restarted. This temporary electronic latch-up failure mode caused by EMP is something that almost never occurs in automobiles during a typical lifetime of operation.

[CynicalSurvival]

No expert, but I do recall someone saying on another thread that a microwave is essentially a Faraday cage. Perhaps an old microwave in the garage etc would be handy makeshift store for hard drives etc until ppl have something more permanent rigged up. If the point about earthing is correct, well, it already has a plug...

[Arzosah]

My most recent post on my blog is about a Faraday Cage ...

[Hamradioop]

Highly recommend

My most recent post on my blog is about a Faraday Cage ...

highly recommended as Arzosah is a top flight researcher.

[Arzosah]

Thank you Hamradioop! I've done my best with this one (as usual) but as you know, I'm *really* not techie. Still, I've explored what I can, and quoted my sources. As I say at the end of the post, hope it helps.